Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

23 files changed, 2575 insertions, 0 deletions

diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264+Private.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264+Private.h
new file mode 100644
index 0000000000..a0cd8515d1
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264+Private.h
@@ -0,0 +1,25 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCCodecSpecificInfoH264.h"
+
+#include "modules/video_coding/include/video_codec_interface.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+/* Interfaces for converting to/from internal C++ formats. */
+@interface RTC_OBJC_TYPE (RTCCodecSpecificInfoH264)
+()
+
+    - (webrtc::CodecSpecificInfo)nativeCodecSpecificInfo;
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.h
new file mode 100644
index 0000000000..ae3003a115
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.h
@@ -0,0 +1,27 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCCodecSpecificInfo.h"
+#import "RTCMacros.h"
+
+/** Class for H264 specific config. */
+typedef NS_ENUM(NSUInteger, RTCH264PacketizationMode) {
+  RTCH264PacketizationModeNonInterleaved = 0,  // Mode 1 - STAP-A, FU-A is allowed
+  RTCH264PacketizationModeSingleNalUnit        // Mode 0 - only single NALU allowed
+};
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCCodecSpecificInfoH264) : NSObject <RTC_OBJC_TYPE(RTCCodecSpecificInfo)>
+
+@property(nonatomic, assign) RTCH264PacketizationMode packetizationMode;
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.mm b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.mm
new file mode 100644
index 0000000000..e38ed307b3
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCCodecSpecificInfoH264.mm
@@ -0,0 +1,29 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCCodecSpecificInfoH264+Private.h"
+
+#import "RTCH264ProfileLevelId.h"
+
+// H264 specific settings.
+@implementation RTC_OBJC_TYPE (RTCCodecSpecificInfoH264)
+
+@synthesize packetizationMode = _packetizationMode;
+
+- (webrtc::CodecSpecificInfo)nativeCodecSpecificInfo {
+  webrtc::CodecSpecificInfo codecSpecificInfo;
+  codecSpecificInfo.codecType = webrtc::kVideoCodecH264;
+  codecSpecificInfo.codecSpecific.H264.packetization_mode =
+      (webrtc::H264PacketizationMode)_packetizationMode;
+
+  return codecSpecificInfo;
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.h
new file mode 100644
index 0000000000..de5a9c4684
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.h
@@ -0,0 +1,26 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoDecoderFactory.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+/** This decoder factory include support for all codecs bundled with WebRTC. If using custom
+ *  codecs, create custom implementations of RTCVideoEncoderFactory and
+ *  RTCVideoDecoderFactory.
+ */
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCDefaultVideoDecoderFactory) : NSObject <RTC_OBJC_TYPE(RTCVideoDecoderFactory)>
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.m b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.m
new file mode 100644
index 0000000000..6e3baa8750
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoDecoderFactory.m
@@ -0,0 +1,85 @@
+/*
+ *  Copyright 2017 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCDefaultVideoDecoderFactory.h"
+
+#import "RTCH264ProfileLevelId.h"
+#import "RTCVideoDecoderH264.h"
+#import "api/video_codec/RTCVideoCodecConstants.h"
+#import "api/video_codec/RTCVideoDecoderVP8.h"
+#import "api/video_codec/RTCVideoDecoderVP9.h"
+#import "base/RTCVideoCodecInfo.h"
+
+#if defined(RTC_DAV1D_IN_INTERNAL_DECODER_FACTORY)
+#import "api/video_codec/RTCVideoDecoderAV1.h"  // nogncheck
+#endif
+
+@implementation RTC_OBJC_TYPE (RTCDefaultVideoDecoderFactory)
+
+- (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs {
+  NSDictionary<NSString *, NSString *> *constrainedHighParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedHigh,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedHighInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecH264Name
+                                                  parameters:constrainedHighParams];
+
+  NSDictionary<NSString *, NSString *> *constrainedBaselineParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedBaseline,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedBaselineInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecH264Name
+                                                  parameters:constrainedBaselineParams];
+
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *vp8Info =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecVp8Name];
+
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *result = [@[
+    constrainedHighInfo,
+    constrainedBaselineInfo,
+    vp8Info,
+  ] mutableCopy];
+
+  if ([RTC_OBJC_TYPE(RTCVideoDecoderVP9) isSupported]) {
+    [result
+        addObject:[[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecVp9Name]];
+  }
+
+#if defined(RTC_DAV1D_IN_INTERNAL_DECODER_FACTORY)
+  [result addObject:[[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecAv1Name]];
+#endif
+
+  return result;
+}
+
+- (id<RTC_OBJC_TYPE(RTCVideoDecoder)>)createDecoder:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)info {
+  if ([info.name isEqualToString:kRTCVideoCodecH264Name]) {
+    return [[RTC_OBJC_TYPE(RTCVideoDecoderH264) alloc] init];
+  } else if ([info.name isEqualToString:kRTCVideoCodecVp8Name]) {
+    return [RTC_OBJC_TYPE(RTCVideoDecoderVP8) vp8Decoder];
+  } else if ([info.name isEqualToString:kRTCVideoCodecVp9Name] &&
+             [RTC_OBJC_TYPE(RTCVideoDecoderVP9) isSupported]) {
+    return [RTC_OBJC_TYPE(RTCVideoDecoderVP9) vp9Decoder];
+  }
+
+#if defined(RTC_DAV1D_IN_INTERNAL_DECODER_FACTORY)
+  if ([info.name isEqualToString:kRTCVideoCodecAv1Name]) {
+    return [RTC_OBJC_TYPE(RTCVideoDecoderAV1) av1Decoder];
+  }
+#endif
+
+  return nil;
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.h
new file mode 100644
index 0000000000..92ab40c95b
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.h
@@ -0,0 +1,31 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoEncoderFactory.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+/** This encoder factory include support for all codecs bundled with WebRTC. If using custom
+ *  codecs, create custom implementations of RTCVideoEncoderFactory and
+ *  RTCVideoDecoderFactory.
+ */
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCDefaultVideoEncoderFactory) : NSObject <RTC_OBJC_TYPE(RTCVideoEncoderFactory)>
+
+@property(nonatomic, retain) RTC_OBJC_TYPE(RTCVideoCodecInfo) *preferredCodec;
+
++ (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs;
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.m b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.m
new file mode 100644
index 0000000000..8de55bde4a
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCDefaultVideoEncoderFactory.m
@@ -0,0 +1,102 @@
+/*
+ *  Copyright 2017 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCDefaultVideoEncoderFactory.h"
+
+#import "RTCH264ProfileLevelId.h"
+#import "RTCVideoEncoderH264.h"
+#import "api/video_codec/RTCVideoCodecConstants.h"
+#import "api/video_codec/RTCVideoEncoderVP8.h"
+#import "api/video_codec/RTCVideoEncoderVP9.h"
+#import "base/RTCVideoCodecInfo.h"
+
+#if defined(RTC_USE_LIBAOM_AV1_ENCODER)
+#import "api/video_codec/RTCVideoEncoderAV1.h"  // nogncheck
+#endif
+
+@implementation RTC_OBJC_TYPE (RTCDefaultVideoEncoderFactory)
+
+@synthesize preferredCodec;
+
++ (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs {
+  NSDictionary<NSString *, NSString *> *constrainedHighParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedHigh,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedHighInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecH264Name
+                                                  parameters:constrainedHighParams];
+
+  NSDictionary<NSString *, NSString *> *constrainedBaselineParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedBaseline,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedBaselineInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecH264Name
+                                                  parameters:constrainedBaselineParams];
+
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *vp8Info =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecVp8Name];
+
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *result = [@[
+    constrainedHighInfo,
+    constrainedBaselineInfo,
+    vp8Info,
+  ] mutableCopy];
+
+  if ([RTC_OBJC_TYPE(RTCVideoEncoderVP9) isSupported]) {
+    [result
+        addObject:[[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecVp9Name]];
+  }
+
+#if defined(RTC_USE_LIBAOM_AV1_ENCODER)
+  [result addObject:[[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:kRTCVideoCodecAv1Name]];
+#endif
+
+  return result;
+}
+
+- (id<RTC_OBJC_TYPE(RTCVideoEncoder)>)createEncoder:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)info {
+  if ([info.name isEqualToString:kRTCVideoCodecH264Name]) {
+    return [[RTC_OBJC_TYPE(RTCVideoEncoderH264) alloc] initWithCodecInfo:info];
+  } else if ([info.name isEqualToString:kRTCVideoCodecVp8Name]) {
+    return [RTC_OBJC_TYPE(RTCVideoEncoderVP8) vp8Encoder];
+  } else if ([info.name isEqualToString:kRTCVideoCodecVp9Name] &&
+             [RTC_OBJC_TYPE(RTCVideoEncoderVP9) isSupported]) {
+    return [RTC_OBJC_TYPE(RTCVideoEncoderVP9) vp9Encoder];
+  }
+
+#if defined(RTC_USE_LIBAOM_AV1_ENCODER)
+  if ([info.name isEqualToString:kRTCVideoCodecAv1Name]) {
+    return [RTC_OBJC_TYPE(RTCVideoEncoderAV1) av1Encoder];
+  }
+#endif
+
+  return nil;
+}
+
+- (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs {
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *codecs =
+      [[[self class] supportedCodecs] mutableCopy];
+
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *orderedCodecs = [NSMutableArray array];
+  NSUInteger index = [codecs indexOfObject:self.preferredCodec];
+  if (index != NSNotFound) {
+    [orderedCodecs addObject:[codecs objectAtIndex:index]];
+    [codecs removeObjectAtIndex:index];
+  }
+  [orderedCodecs addObjectsFromArray:codecs];
+
+  return [orderedCodecs copy];
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.h
new file mode 100644
index 0000000000..dac7bb5610
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.h
@@ -0,0 +1,60 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+
+RTC_OBJC_EXPORT extern NSString *const kRTCVideoCodecH264Name;
+RTC_OBJC_EXPORT extern NSString *const kRTCLevel31ConstrainedHigh;
+RTC_OBJC_EXPORT extern NSString *const kRTCLevel31ConstrainedBaseline;
+RTC_OBJC_EXPORT extern NSString *const kRTCMaxSupportedH264ProfileLevelConstrainedHigh;
+RTC_OBJC_EXPORT extern NSString *const kRTCMaxSupportedH264ProfileLevelConstrainedBaseline;
+
+/** H264 Profiles and levels. */
+typedef NS_ENUM(NSUInteger, RTCH264Profile) {
+  RTCH264ProfileConstrainedBaseline,
+  RTCH264ProfileBaseline,
+  RTCH264ProfileMain,
+  RTCH264ProfileConstrainedHigh,
+  RTCH264ProfileHigh,
+};
+
+typedef NS_ENUM(NSUInteger, RTCH264Level) {
+  RTCH264Level1_b = 0,
+  RTCH264Level1 = 10,
+  RTCH264Level1_1 = 11,
+  RTCH264Level1_2 = 12,
+  RTCH264Level1_3 = 13,
+  RTCH264Level2 = 20,
+  RTCH264Level2_1 = 21,
+  RTCH264Level2_2 = 22,
+  RTCH264Level3 = 30,
+  RTCH264Level3_1 = 31,
+  RTCH264Level3_2 = 32,
+  RTCH264Level4 = 40,
+  RTCH264Level4_1 = 41,
+  RTCH264Level4_2 = 42,
+  RTCH264Level5 = 50,
+  RTCH264Level5_1 = 51,
+  RTCH264Level5_2 = 52
+};
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCH264ProfileLevelId) : NSObject
+
+@property(nonatomic, readonly) RTCH264Profile profile;
+@property(nonatomic, readonly) RTCH264Level level;
+@property(nonatomic, readonly) NSString *hexString;
+
+- (instancetype)initWithHexString:(NSString *)hexString;
+- (instancetype)initWithProfile:(RTCH264Profile)profile level:(RTCH264Level)level;
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.mm b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.mm
new file mode 100644
index 0000000000..f0ef3ec232
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCH264ProfileLevelId.mm
@@ -0,0 +1,120 @@
+/*
+ *  Copyright 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#import "RTCH264ProfileLevelId.h"
+
+#import "helpers/NSString+StdString.h"
+#if defined(WEBRTC_IOS)
+#import "UIDevice+H264Profile.h"
+#endif
+
+#include "api/video_codecs/h264_profile_level_id.h"
+#include "media/base/media_constants.h"
+
+namespace {
+
+NSString *MaxSupportedProfileLevelConstrainedHigh();
+NSString *MaxSupportedProfileLevelConstrainedBaseline();
+
+}  // namespace
+
+NSString *const kRTCVideoCodecH264Name = @(cricket::kH264CodecName);
+NSString *const kRTCLevel31ConstrainedHigh = @"640c1f";
+NSString *const kRTCLevel31ConstrainedBaseline = @"42e01f";
+NSString *const kRTCMaxSupportedH264ProfileLevelConstrainedHigh =
+    MaxSupportedProfileLevelConstrainedHigh();
+NSString *const kRTCMaxSupportedH264ProfileLevelConstrainedBaseline =
+    MaxSupportedProfileLevelConstrainedBaseline();
+
+namespace {
+
+#if defined(WEBRTC_IOS)
+
+NSString *MaxSupportedLevelForProfile(webrtc::H264Profile profile) {
+  const absl::optional<webrtc::H264ProfileLevelId> profileLevelId =
+      [UIDevice maxSupportedH264Profile];
+  if (profileLevelId && profileLevelId->profile >= profile) {
+    const absl::optional<std::string> profileString =
+        H264ProfileLevelIdToString(webrtc::H264ProfileLevelId(profile, profileLevelId->level));
+    if (profileString) {
+      return [NSString stringForStdString:*profileString];
+    }
+  }
+  return nil;
+}
+#endif
+
+NSString *MaxSupportedProfileLevelConstrainedBaseline() {
+#if defined(WEBRTC_IOS)
+  NSString *profile = MaxSupportedLevelForProfile(webrtc::H264Profile::kProfileConstrainedBaseline);
+  if (profile != nil) {
+    return profile;
+  }
+#endif
+  return kRTCLevel31ConstrainedBaseline;
+}
+
+NSString *MaxSupportedProfileLevelConstrainedHigh() {
+#if defined(WEBRTC_IOS)
+  NSString *profile = MaxSupportedLevelForProfile(webrtc::H264Profile::kProfileConstrainedHigh);
+  if (profile != nil) {
+    return profile;
+  }
+#endif
+  return kRTCLevel31ConstrainedHigh;
+}
+
+}  // namespace
+
+@interface RTC_OBJC_TYPE (RTCH264ProfileLevelId)
+()
+
+    @property(nonatomic, assign) RTCH264Profile profile;
+@property(nonatomic, assign) RTCH264Level level;
+@property(nonatomic, strong) NSString *hexString;
+
+@end
+
+@implementation RTC_OBJC_TYPE (RTCH264ProfileLevelId)
+
+@synthesize profile = _profile;
+@synthesize level = _level;
+@synthesize hexString = _hexString;
+
+- (instancetype)initWithHexString:(NSString *)hexString {
+  if (self = [super init]) {
+    self.hexString = hexString;
+
+    absl::optional<webrtc::H264ProfileLevelId> profile_level_id =
+        webrtc::ParseH264ProfileLevelId([hexString cStringUsingEncoding:NSUTF8StringEncoding]);
+    if (profile_level_id.has_value()) {
+      self.profile = static_cast<RTCH264Profile>(profile_level_id->profile);
+      self.level = static_cast<RTCH264Level>(profile_level_id->level);
+    }
+  }
+  return self;
+}
+
+- (instancetype)initWithProfile:(RTCH264Profile)profile level:(RTCH264Level)level {
+  if (self = [super init]) {
+    self.profile = profile;
+    self.level = level;
+
+    absl::optional<std::string> hex_string =
+        webrtc::H264ProfileLevelIdToString(webrtc::H264ProfileLevelId(
+            static_cast<webrtc::H264Profile>(profile), static_cast<webrtc::H264Level>(level)));
+    self.hexString =
+        [NSString stringWithCString:hex_string.value_or("").c_str() encoding:NSUTF8StringEncoding];
+  }
+  return self;
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.h
new file mode 100644
index 0000000000..88bacbbdfe
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.h
@@ -0,0 +1,18 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoDecoderFactory.h"
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCVideoDecoderFactoryH264) : NSObject <RTC_OBJC_TYPE(RTCVideoDecoderFactory)>
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.m b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.m
new file mode 100644
index 0000000000..bdae19d687
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderFactoryH264.m
@@ -0,0 +1,49 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCVideoDecoderFactoryH264.h"
+
+#import "RTCH264ProfileLevelId.h"
+#import "RTCVideoDecoderH264.h"
+
+@implementation RTC_OBJC_TYPE (RTCVideoDecoderFactoryH264)
+
+- (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs {
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *codecs = [NSMutableArray array];
+  NSString *codecName = kRTCVideoCodecH264Name;
+
+  NSDictionary<NSString *, NSString *> *constrainedHighParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedHigh,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedHighInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:codecName
+                                                  parameters:constrainedHighParams];
+  [codecs addObject:constrainedHighInfo];
+
+  NSDictionary<NSString *, NSString *> *constrainedBaselineParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedBaseline,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedBaselineInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:codecName
+                                                  parameters:constrainedBaselineParams];
+  [codecs addObject:constrainedBaselineInfo];
+
+  return [codecs copy];
+}
+
+- (id<RTC_OBJC_TYPE(RTCVideoDecoder)>)createDecoder:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)info {
+  return [[RTC_OBJC_TYPE(RTCVideoDecoderH264) alloc] init];
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.h
new file mode 100644
index 0000000000..a12e4212a7
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.h
@@ -0,0 +1,18 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoDecoder.h"
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCVideoDecoderH264) : NSObject <RTC_OBJC_TYPE(RTCVideoDecoder)>
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.mm b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.mm
new file mode 100644
index 0000000000..09e642bc37
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoDecoderH264.mm
@@ -0,0 +1,276 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#import "RTCVideoDecoderH264.h"
+
+#import <VideoToolbox/VideoToolbox.h>
+
+#import "base/RTCVideoFrame.h"
+#import "base/RTCVideoFrameBuffer.h"
+#import "components/video_frame_buffer/RTCCVPixelBuffer.h"
+#import "helpers.h"
+#import "helpers/scoped_cftyperef.h"
+
+#if defined(WEBRTC_IOS)
+#import "helpers/UIDevice+RTCDevice.h"
+#endif
+
+#include "modules/video_coding/include/video_error_codes.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/time_utils.h"
+#include "sdk/objc/components/video_codec/nalu_rewriter.h"
+
+// Struct that we pass to the decoder per frame to decode. We receive it again
+// in the decoder callback.
+struct RTCFrameDecodeParams {
+  RTCFrameDecodeParams(RTCVideoDecoderCallback cb, int64_t ts) : callback(cb), timestamp(ts) {}
+  RTCVideoDecoderCallback callback;
+  int64_t timestamp;
+};
+
+@interface RTC_OBJC_TYPE (RTCVideoDecoderH264)
+() - (void)setError : (OSStatus)error;
+@end
+
+// This is the callback function that VideoToolbox calls when decode is
+// complete.
+void decompressionOutputCallback(void *decoderRef,
+                                 void *params,
+                                 OSStatus status,
+                                 VTDecodeInfoFlags infoFlags,
+                                 CVImageBufferRef imageBuffer,
+                                 CMTime timestamp,
+                                 CMTime duration) {
+  std::unique_ptr<RTCFrameDecodeParams> decodeParams(
+      reinterpret_cast<RTCFrameDecodeParams *>(params));
+  if (status != noErr) {
+    RTC_OBJC_TYPE(RTCVideoDecoderH264) *decoder =
+        (__bridge RTC_OBJC_TYPE(RTCVideoDecoderH264) *)decoderRef;
+    [decoder setError:status];
+    RTC_LOG(LS_ERROR) << "Failed to decode frame. Status: " << status;
+    return;
+  }
+  // TODO(tkchin): Handle CVO properly.
+  RTC_OBJC_TYPE(RTCCVPixelBuffer) *frameBuffer =
+      [[RTC_OBJC_TYPE(RTCCVPixelBuffer) alloc] initWithPixelBuffer:imageBuffer];
+  RTC_OBJC_TYPE(RTCVideoFrame) *decodedFrame = [[RTC_OBJC_TYPE(RTCVideoFrame) alloc]
+      initWithBuffer:frameBuffer
+            rotation:RTCVideoRotation_0
+         timeStampNs:CMTimeGetSeconds(timestamp) * rtc::kNumNanosecsPerSec];
+  decodedFrame.timeStamp = decodeParams->timestamp;
+  decodeParams->callback(decodedFrame);
+}
+
+// Decoder.
+@implementation RTC_OBJC_TYPE (RTCVideoDecoderH264) {
+  CMVideoFormatDescriptionRef _videoFormat;
+  CMMemoryPoolRef _memoryPool;
+  VTDecompressionSessionRef _decompressionSession;
+  RTCVideoDecoderCallback _callback;
+  OSStatus _error;
+}
+
+- (instancetype)init {
+  self = [super init];
+  if (self) {
+    _memoryPool = CMMemoryPoolCreate(nil);
+  }
+  return self;
+}
+
+- (void)dealloc {
+  CMMemoryPoolInvalidate(_memoryPool);
+  CFRelease(_memoryPool);
+  [self destroyDecompressionSession];
+  [self setVideoFormat:nullptr];
+}
+
+- (NSInteger)startDecodeWithNumberOfCores:(int)numberOfCores {
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (NSInteger)decode:(RTC_OBJC_TYPE(RTCEncodedImage) *)inputImage
+        missingFrames:(BOOL)missingFrames
+    codecSpecificInfo:(nullable id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)info
+         renderTimeMs:(int64_t)renderTimeMs {
+  RTC_DCHECK(inputImage.buffer);
+
+  if (_error != noErr) {
+    RTC_LOG(LS_WARNING) << "Last frame decode failed.";
+    _error = noErr;
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+
+  rtc::ScopedCFTypeRef<CMVideoFormatDescriptionRef> inputFormat =
+      rtc::ScopedCF(webrtc::CreateVideoFormatDescription((uint8_t *)inputImage.buffer.bytes,
+                                                         inputImage.buffer.length));
+  if (inputFormat) {
+    // Check if the video format has changed, and reinitialize decoder if
+    // needed.
+    if (!CMFormatDescriptionEqual(inputFormat.get(), _videoFormat)) {
+      [self setVideoFormat:inputFormat.get()];
+      int resetDecompressionSessionError = [self resetDecompressionSession];
+      if (resetDecompressionSessionError != WEBRTC_VIDEO_CODEC_OK) {
+        return resetDecompressionSessionError;
+      }
+    }
+  }
+  if (!_videoFormat) {
+    // We received a frame but we don't have format information so we can't
+    // decode it.
+    // This can happen after backgrounding. We need to wait for the next
+    // sps/pps before we can resume so we request a keyframe by returning an
+    // error.
+    RTC_LOG(LS_WARNING) << "Missing video format. Frame with sps/pps required.";
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  CMSampleBufferRef sampleBuffer = nullptr;
+  if (!webrtc::H264AnnexBBufferToCMSampleBuffer((uint8_t *)inputImage.buffer.bytes,
+                                                inputImage.buffer.length,
+                                                _videoFormat,
+                                                &sampleBuffer,
+                                                _memoryPool)) {
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  RTC_DCHECK(sampleBuffer);
+  VTDecodeFrameFlags decodeFlags = kVTDecodeFrame_EnableAsynchronousDecompression;
+  std::unique_ptr<RTCFrameDecodeParams> frameDecodeParams;
+  frameDecodeParams.reset(new RTCFrameDecodeParams(_callback, inputImage.timeStamp));
+  OSStatus status = VTDecompressionSessionDecodeFrame(
+      _decompressionSession, sampleBuffer, decodeFlags, frameDecodeParams.release(), nullptr);
+#if defined(WEBRTC_IOS)
+  // Re-initialize the decoder if we have an invalid session while the app is
+  // active or decoder malfunctions and retry the decode request.
+  if ((status == kVTInvalidSessionErr || status == kVTVideoDecoderMalfunctionErr) &&
+      [self resetDecompressionSession] == WEBRTC_VIDEO_CODEC_OK) {
+    RTC_LOG(LS_INFO) << "Failed to decode frame with code: " << status
+                     << " retrying decode after decompression session reset";
+    frameDecodeParams.reset(new RTCFrameDecodeParams(_callback, inputImage.timeStamp));
+    status = VTDecompressionSessionDecodeFrame(
+        _decompressionSession, sampleBuffer, decodeFlags, frameDecodeParams.release(), nullptr);
+  }
+#endif
+  CFRelease(sampleBuffer);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to decode frame with code: " << status;
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (void)setCallback:(RTCVideoDecoderCallback)callback {
+  _callback = callback;
+}
+
+- (void)setError:(OSStatus)error {
+  _error = error;
+}
+
+- (NSInteger)releaseDecoder {
+  // Need to invalidate the session so that callbacks no longer occur and it
+  // is safe to null out the callback.
+  [self destroyDecompressionSession];
+  [self setVideoFormat:nullptr];
+  _callback = nullptr;
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+#pragma mark - Private
+
+- (int)resetDecompressionSession {
+  [self destroyDecompressionSession];
+
+  // Need to wait for the first SPS to initialize decoder.
+  if (!_videoFormat) {
+    return WEBRTC_VIDEO_CODEC_OK;
+  }
+
+  // Set keys for OpenGL and IOSurface compatibilty, which makes the encoder
+  // create pixel buffers with GPU backed memory. The intent here is to pass
+  // the pixel buffers directly so we avoid a texture upload later during
+  // rendering. This currently is moot because we are converting back to an
+  // I420 frame after decode, but eventually we will be able to plumb
+  // CVPixelBuffers directly to the renderer.
+  // TODO(tkchin): Maybe only set OpenGL/IOSurface keys if we know that that
+  // we can pass CVPixelBuffers as native handles in decoder output.
+  NSDictionary *attributes = @{
+#if defined(WEBRTC_IOS) && (TARGET_OS_MACCATALYST || TARGET_OS_SIMULATOR)
+    (NSString *)kCVPixelBufferMetalCompatibilityKey : @(YES),
+#elif defined(WEBRTC_IOS)
+    (NSString *)kCVPixelBufferOpenGLESCompatibilityKey : @(YES),
+#elif defined(WEBRTC_MAC) && !defined(WEBRTC_ARCH_ARM64)
+    (NSString *)kCVPixelBufferOpenGLCompatibilityKey : @(YES),
+#endif
+#if !(TARGET_OS_SIMULATOR)
+    (NSString *)kCVPixelBufferIOSurfacePropertiesKey : @{},
+#endif
+    (NSString *)
+    kCVPixelBufferPixelFormatTypeKey : @(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange),
+  };
+
+  VTDecompressionOutputCallbackRecord record = {
+      decompressionOutputCallback, (__bridge void *)self,
+  };
+  OSStatus status = VTDecompressionSessionCreate(nullptr,
+                                                 _videoFormat,
+                                                 nullptr,
+                                                 (__bridge CFDictionaryRef)attributes,
+                                                 &record,
+                                                 &_decompressionSession);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to create decompression session: " << status;
+    [self destroyDecompressionSession];
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  [self configureDecompressionSession];
+
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (void)configureDecompressionSession {
+  RTC_DCHECK(_decompressionSession);
+#if defined(WEBRTC_IOS)
+  VTSessionSetProperty(_decompressionSession, kVTDecompressionPropertyKey_RealTime, kCFBooleanTrue);
+#endif
+}
+
+- (void)destroyDecompressionSession {
+  if (_decompressionSession) {
+#if defined(WEBRTC_IOS)
+    if ([UIDevice isIOS11OrLater]) {
+      VTDecompressionSessionWaitForAsynchronousFrames(_decompressionSession);
+    }
+#endif
+    VTDecompressionSessionInvalidate(_decompressionSession);
+    CFRelease(_decompressionSession);
+    _decompressionSession = nullptr;
+  }
+}
+
+- (void)setVideoFormat:(CMVideoFormatDescriptionRef)videoFormat {
+  if (_videoFormat == videoFormat) {
+    return;
+  }
+  if (_videoFormat) {
+    CFRelease(_videoFormat);
+  }
+  _videoFormat = videoFormat;
+  if (_videoFormat) {
+    CFRetain(_videoFormat);
+  }
+}
+
+- (NSString *)implementationName {
+  return @"VideoToolbox";
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.h
new file mode 100644
index 0000000000..45fc4be2ea
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.h
@@ -0,0 +1,18 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoEncoderFactory.h"
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCVideoEncoderFactoryH264) : NSObject <RTC_OBJC_TYPE(RTCVideoEncoderFactory)>
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.m b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.m
new file mode 100644
index 0000000000..9843849307
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderFactoryH264.m
@@ -0,0 +1,49 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCVideoEncoderFactoryH264.h"
+
+#import "RTCH264ProfileLevelId.h"
+#import "RTCVideoEncoderH264.h"
+
+@implementation RTC_OBJC_TYPE (RTCVideoEncoderFactoryH264)
+
+- (NSArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *)supportedCodecs {
+  NSMutableArray<RTC_OBJC_TYPE(RTCVideoCodecInfo) *> *codecs = [NSMutableArray array];
+  NSString *codecName = kRTCVideoCodecH264Name;
+
+  NSDictionary<NSString *, NSString *> *constrainedHighParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedHigh,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedHighInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:codecName
+                                                  parameters:constrainedHighParams];
+  [codecs addObject:constrainedHighInfo];
+
+  NSDictionary<NSString *, NSString *> *constrainedBaselineParams = @{
+    @"profile-level-id" : kRTCMaxSupportedH264ProfileLevelConstrainedBaseline,
+    @"level-asymmetry-allowed" : @"1",
+    @"packetization-mode" : @"1",
+  };
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) *constrainedBaselineInfo =
+      [[RTC_OBJC_TYPE(RTCVideoCodecInfo) alloc] initWithName:codecName
+                                                  parameters:constrainedBaselineParams];
+  [codecs addObject:constrainedBaselineInfo];
+
+  return [codecs copy];
+}
+
+- (id<RTC_OBJC_TYPE(RTCVideoEncoder)>)createEncoder:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)info {
+  return [[RTC_OBJC_TYPE(RTCVideoEncoderH264) alloc] initWithCodecInfo:info];
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.h b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.h
new file mode 100644
index 0000000000..9f4f4c7c8d
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.h
@@ -0,0 +1,22 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RTCMacros.h"
+#import "RTCVideoCodecInfo.h"
+#import "RTCVideoEncoder.h"
+
+RTC_OBJC_EXPORT
+@interface RTC_OBJC_TYPE (RTCVideoEncoderH264) : NSObject <RTC_OBJC_TYPE(RTCVideoEncoder)>
+
+- (instancetype)initWithCodecInfo:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)codecInfo;
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm
new file mode 100644
index 0000000000..7dbbfaf019
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/RTCVideoEncoderH264.mm
@@ -0,0 +1,819 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#import "RTCVideoEncoderH264.h"
+
+#import <VideoToolbox/VideoToolbox.h>
+#include <vector>
+
+#if defined(WEBRTC_IOS)
+#import "helpers/UIDevice+RTCDevice.h"
+#endif
+#import "RTCCodecSpecificInfoH264.h"
+#import "RTCH264ProfileLevelId.h"
+#import "api/peerconnection/RTCVideoCodecInfo+Private.h"
+#import "base/RTCCodecSpecificInfo.h"
+#import "base/RTCI420Buffer.h"
+#import "base/RTCVideoEncoder.h"
+#import "base/RTCVideoFrame.h"
+#import "base/RTCVideoFrameBuffer.h"
+#import "components/video_frame_buffer/RTCCVPixelBuffer.h"
+#import "helpers.h"
+
+#include "api/video_codecs/h264_profile_level_id.h"
+#include "common_video/h264/h264_bitstream_parser.h"
+#include "common_video/include/bitrate_adjuster.h"
+#include "modules/video_coding/include/video_error_codes.h"
+#include "rtc_base/buffer.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/time_utils.h"
+#include "sdk/objc/components/video_codec/nalu_rewriter.h"
+#include "third_party/libyuv/include/libyuv/convert_from.h"
+
+@interface RTC_OBJC_TYPE (RTCVideoEncoderH264)
+()
+
+    - (void)frameWasEncoded : (OSStatus)status flags : (VTEncodeInfoFlags)infoFlags sampleBuffer
+    : (CMSampleBufferRef)sampleBuffer codecSpecificInfo
+    : (id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo width : (int32_t)width height
+    : (int32_t)height renderTimeMs : (int64_t)renderTimeMs timestamp : (uint32_t)timestamp rotation
+    : (RTCVideoRotation)rotation;
+
+@end
+
+namespace {  // anonymous namespace
+
+// The ratio between kVTCompressionPropertyKey_DataRateLimits and
+// kVTCompressionPropertyKey_AverageBitRate. The data rate limit is set higher
+// than the average bit rate to avoid undershooting the target.
+const float kLimitToAverageBitRateFactor = 1.5f;
+// These thresholds deviate from the default h264 QP thresholds, as they
+// have been found to work better on devices that support VideoToolbox
+const int kLowH264QpThreshold = 28;
+const int kHighH264QpThreshold = 39;
+
+const OSType kNV12PixelFormat = kCVPixelFormatType_420YpCbCr8BiPlanarFullRange;
+
+// Struct that we pass to the encoder per frame to encode. We receive it again
+// in the encoder callback.
+struct RTCFrameEncodeParams {
+  RTCFrameEncodeParams(RTC_OBJC_TYPE(RTCVideoEncoderH264) * e,
+                       RTC_OBJC_TYPE(RTCCodecSpecificInfoH264) * csi,
+                       int32_t w,
+                       int32_t h,
+                       int64_t rtms,
+                       uint32_t ts,
+                       RTCVideoRotation r)
+      : encoder(e), width(w), height(h), render_time_ms(rtms), timestamp(ts), rotation(r) {
+    if (csi) {
+      codecSpecificInfo = csi;
+    } else {
+      codecSpecificInfo = [[RTC_OBJC_TYPE(RTCCodecSpecificInfoH264) alloc] init];
+    }
+  }
+
+  RTC_OBJC_TYPE(RTCVideoEncoderH264) * encoder;
+  RTC_OBJC_TYPE(RTCCodecSpecificInfoH264) * codecSpecificInfo;
+  int32_t width;
+  int32_t height;
+  int64_t render_time_ms;
+  uint32_t timestamp;
+  RTCVideoRotation rotation;
+};
+
+// We receive I420Frames as input, but we need to feed CVPixelBuffers into the
+// encoder. This performs the copy and format conversion.
+// TODO(tkchin): See if encoder will accept i420 frames and compare performance.
+bool CopyVideoFrameToNV12PixelBuffer(id<RTC_OBJC_TYPE(RTCI420Buffer)> frameBuffer,
+                                     CVPixelBufferRef pixelBuffer) {
+  RTC_DCHECK(pixelBuffer);
+  RTC_DCHECK_EQ(CVPixelBufferGetPixelFormatType(pixelBuffer), kNV12PixelFormat);
+  RTC_DCHECK_EQ(CVPixelBufferGetHeightOfPlane(pixelBuffer, 0), frameBuffer.height);
+  RTC_DCHECK_EQ(CVPixelBufferGetWidthOfPlane(pixelBuffer, 0), frameBuffer.width);
+
+  CVReturn cvRet = CVPixelBufferLockBaseAddress(pixelBuffer, 0);
+  if (cvRet != kCVReturnSuccess) {
+    RTC_LOG(LS_ERROR) << "Failed to lock base address: " << cvRet;
+    return false;
+  }
+  uint8_t *dstY = reinterpret_cast<uint8_t *>(CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0));
+  int dstStrideY = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);
+  uint8_t *dstUV = reinterpret_cast<uint8_t *>(CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1));
+  int dstStrideUV = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 1);
+  // Convert I420 to NV12.
+  int ret = libyuv::I420ToNV12(frameBuffer.dataY,
+                               frameBuffer.strideY,
+                               frameBuffer.dataU,
+                               frameBuffer.strideU,
+                               frameBuffer.dataV,
+                               frameBuffer.strideV,
+                               dstY,
+                               dstStrideY,
+                               dstUV,
+                               dstStrideUV,
+                               frameBuffer.width,
+                               frameBuffer.height);
+  CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);
+  if (ret) {
+    RTC_LOG(LS_ERROR) << "Error converting I420 VideoFrame to NV12 :" << ret;
+    return false;
+  }
+  return true;
+}
+
+CVPixelBufferRef CreatePixelBuffer(CVPixelBufferPoolRef pixel_buffer_pool) {
+  if (!pixel_buffer_pool) {
+    RTC_LOG(LS_ERROR) << "Failed to get pixel buffer pool.";
+    return nullptr;
+  }
+  CVPixelBufferRef pixel_buffer;
+  CVReturn ret = CVPixelBufferPoolCreatePixelBuffer(nullptr, pixel_buffer_pool, &pixel_buffer);
+  if (ret != kCVReturnSuccess) {
+    RTC_LOG(LS_ERROR) << "Failed to create pixel buffer: " << ret;
+    // We probably want to drop frames here, since failure probably means
+    // that the pool is empty.
+    return nullptr;
+  }
+  return pixel_buffer;
+}
+
+// This is the callback function that VideoToolbox calls when encode is
+// complete. From inspection this happens on its own queue.
+void compressionOutputCallback(void *encoder,
+                               void *params,
+                               OSStatus status,
+                               VTEncodeInfoFlags infoFlags,
+                               CMSampleBufferRef sampleBuffer) {
+  if (!params) {
+    // If there are pending callbacks when the encoder is destroyed, this can happen.
+    return;
+  }
+  std::unique_ptr<RTCFrameEncodeParams> encodeParams(
+      reinterpret_cast<RTCFrameEncodeParams *>(params));
+  [encodeParams->encoder frameWasEncoded:status
+                                   flags:infoFlags
+                            sampleBuffer:sampleBuffer
+                       codecSpecificInfo:encodeParams->codecSpecificInfo
+                                   width:encodeParams->width
+                                  height:encodeParams->height
+                            renderTimeMs:encodeParams->render_time_ms
+                               timestamp:encodeParams->timestamp
+                                rotation:encodeParams->rotation];
+}
+
+// Extract VideoToolbox profile out of the webrtc::SdpVideoFormat. If there is
+// no specific VideoToolbox profile for the specified level, AutoLevel will be
+// returned. The user must initialize the encoder with a resolution and
+// framerate conforming to the selected H264 level regardless.
+CFStringRef ExtractProfile(const webrtc::H264ProfileLevelId &profile_level_id) {
+  switch (profile_level_id.profile) {
+    case webrtc::H264Profile::kProfileConstrainedBaseline:
+    case webrtc::H264Profile::kProfileBaseline:
+      switch (profile_level_id.level) {
+        case webrtc::H264Level::kLevel3:
+          return kVTProfileLevel_H264_Baseline_3_0;
+        case webrtc::H264Level::kLevel3_1:
+          return kVTProfileLevel_H264_Baseline_3_1;
+        case webrtc::H264Level::kLevel3_2:
+          return kVTProfileLevel_H264_Baseline_3_2;
+        case webrtc::H264Level::kLevel4:
+          return kVTProfileLevel_H264_Baseline_4_0;
+        case webrtc::H264Level::kLevel4_1:
+          return kVTProfileLevel_H264_Baseline_4_1;
+        case webrtc::H264Level::kLevel4_2:
+          return kVTProfileLevel_H264_Baseline_4_2;
+        case webrtc::H264Level::kLevel5:
+          return kVTProfileLevel_H264_Baseline_5_0;
+        case webrtc::H264Level::kLevel5_1:
+          return kVTProfileLevel_H264_Baseline_5_1;
+        case webrtc::H264Level::kLevel5_2:
+          return kVTProfileLevel_H264_Baseline_5_2;
+        case webrtc::H264Level::kLevel1:
+        case webrtc::H264Level::kLevel1_b:
+        case webrtc::H264Level::kLevel1_1:
+        case webrtc::H264Level::kLevel1_2:
+        case webrtc::H264Level::kLevel1_3:
+        case webrtc::H264Level::kLevel2:
+        case webrtc::H264Level::kLevel2_1:
+        case webrtc::H264Level::kLevel2_2:
+          return kVTProfileLevel_H264_Baseline_AutoLevel;
+      }
+
+    case webrtc::H264Profile::kProfileMain:
+      switch (profile_level_id.level) {
+        case webrtc::H264Level::kLevel3:
+          return kVTProfileLevel_H264_Main_3_0;
+        case webrtc::H264Level::kLevel3_1:
+          return kVTProfileLevel_H264_Main_3_1;
+        case webrtc::H264Level::kLevel3_2:
+          return kVTProfileLevel_H264_Main_3_2;
+        case webrtc::H264Level::kLevel4:
+          return kVTProfileLevel_H264_Main_4_0;
+        case webrtc::H264Level::kLevel4_1:
+          return kVTProfileLevel_H264_Main_4_1;
+        case webrtc::H264Level::kLevel4_2:
+          return kVTProfileLevel_H264_Main_4_2;
+        case webrtc::H264Level::kLevel5:
+          return kVTProfileLevel_H264_Main_5_0;
+        case webrtc::H264Level::kLevel5_1:
+          return kVTProfileLevel_H264_Main_5_1;
+        case webrtc::H264Level::kLevel5_2:
+          return kVTProfileLevel_H264_Main_5_2;
+        case webrtc::H264Level::kLevel1:
+        case webrtc::H264Level::kLevel1_b:
+        case webrtc::H264Level::kLevel1_1:
+        case webrtc::H264Level::kLevel1_2:
+        case webrtc::H264Level::kLevel1_3:
+        case webrtc::H264Level::kLevel2:
+        case webrtc::H264Level::kLevel2_1:
+        case webrtc::H264Level::kLevel2_2:
+          return kVTProfileLevel_H264_Main_AutoLevel;
+      }
+
+    case webrtc::H264Profile::kProfileConstrainedHigh:
+    case webrtc::H264Profile::kProfileHigh:
+    case webrtc::H264Profile::kProfilePredictiveHigh444:
+      switch (profile_level_id.level) {
+        case webrtc::H264Level::kLevel3:
+          return kVTProfileLevel_H264_High_3_0;
+        case webrtc::H264Level::kLevel3_1:
+          return kVTProfileLevel_H264_High_3_1;
+        case webrtc::H264Level::kLevel3_2:
+          return kVTProfileLevel_H264_High_3_2;
+        case webrtc::H264Level::kLevel4:
+          return kVTProfileLevel_H264_High_4_0;
+        case webrtc::H264Level::kLevel4_1:
+          return kVTProfileLevel_H264_High_4_1;
+        case webrtc::H264Level::kLevel4_2:
+          return kVTProfileLevel_H264_High_4_2;
+        case webrtc::H264Level::kLevel5:
+          return kVTProfileLevel_H264_High_5_0;
+        case webrtc::H264Level::kLevel5_1:
+          return kVTProfileLevel_H264_High_5_1;
+        case webrtc::H264Level::kLevel5_2:
+          return kVTProfileLevel_H264_High_5_2;
+        case webrtc::H264Level::kLevel1:
+        case webrtc::H264Level::kLevel1_b:
+        case webrtc::H264Level::kLevel1_1:
+        case webrtc::H264Level::kLevel1_2:
+        case webrtc::H264Level::kLevel1_3:
+        case webrtc::H264Level::kLevel2:
+        case webrtc::H264Level::kLevel2_1:
+        case webrtc::H264Level::kLevel2_2:
+          return kVTProfileLevel_H264_High_AutoLevel;
+      }
+  }
+}
+
+// The function returns the max allowed sample rate (pixels per second) that
+// can be processed by given encoder with `profile_level_id`.
+// See https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-H.264-201610-S!!PDF-E&type=items
+// for details.
+NSUInteger GetMaxSampleRate(const webrtc::H264ProfileLevelId &profile_level_id) {
+  switch (profile_level_id.level) {
+    case webrtc::H264Level::kLevel3:
+      return 10368000;
+    case webrtc::H264Level::kLevel3_1:
+      return 27648000;
+    case webrtc::H264Level::kLevel3_2:
+      return 55296000;
+    case webrtc::H264Level::kLevel4:
+    case webrtc::H264Level::kLevel4_1:
+      return 62914560;
+    case webrtc::H264Level::kLevel4_2:
+      return 133693440;
+    case webrtc::H264Level::kLevel5:
+      return 150994944;
+    case webrtc::H264Level::kLevel5_1:
+      return 251658240;
+    case webrtc::H264Level::kLevel5_2:
+      return 530841600;
+    case webrtc::H264Level::kLevel1:
+    case webrtc::H264Level::kLevel1_b:
+    case webrtc::H264Level::kLevel1_1:
+    case webrtc::H264Level::kLevel1_2:
+    case webrtc::H264Level::kLevel1_3:
+    case webrtc::H264Level::kLevel2:
+    case webrtc::H264Level::kLevel2_1:
+    case webrtc::H264Level::kLevel2_2:
+      // Zero means auto rate setting.
+      return 0;
+  }
+}
+}  // namespace
+
+@implementation RTC_OBJC_TYPE (RTCVideoEncoderH264) {
+  RTC_OBJC_TYPE(RTCVideoCodecInfo) * _codecInfo;
+  std::unique_ptr<webrtc::BitrateAdjuster> _bitrateAdjuster;
+  uint32_t _targetBitrateBps;
+  uint32_t _encoderBitrateBps;
+  uint32_t _encoderFrameRate;
+  uint32_t _maxAllowedFrameRate;
+  RTCH264PacketizationMode _packetizationMode;
+  absl::optional<webrtc::H264ProfileLevelId> _profile_level_id;
+  RTCVideoEncoderCallback _callback;
+  int32_t _width;
+  int32_t _height;
+  VTCompressionSessionRef _compressionSession;
+  CVPixelBufferPoolRef _pixelBufferPool;
+  RTCVideoCodecMode _mode;
+
+  webrtc::H264BitstreamParser _h264BitstreamParser;
+  std::vector<uint8_t> _frameScaleBuffer;
+}
+
+// .5 is set as a mininum to prevent overcompensating for large temporary
+// overshoots. We don't want to degrade video quality too badly.
+// .95 is set to prevent oscillations. When a lower bitrate is set on the
+// encoder than previously set, its output seems to have a brief period of
+// drastically reduced bitrate, so we want to avoid that. In steady state
+// conditions, 0.95 seems to give us better overall bitrate over long periods
+// of time.
+- (instancetype)initWithCodecInfo:(RTC_OBJC_TYPE(RTCVideoCodecInfo) *)codecInfo {
+  if (self = [super init]) {
+    _codecInfo = codecInfo;
+    _bitrateAdjuster.reset(new webrtc::BitrateAdjuster(.5, .95));
+    _packetizationMode = RTCH264PacketizationModeNonInterleaved;
+    _profile_level_id =
+        webrtc::ParseSdpForH264ProfileLevelId([codecInfo nativeSdpVideoFormat].parameters);
+    RTC_DCHECK(_profile_level_id);
+    RTC_LOG(LS_INFO) << "Using profile " << CFStringToString(ExtractProfile(*_profile_level_id));
+    RTC_CHECK([codecInfo.name isEqualToString:kRTCVideoCodecH264Name]);
+  }
+  return self;
+}
+
+- (void)dealloc {
+  [self destroyCompressionSession];
+}
+
+- (NSInteger)startEncodeWithSettings:(RTC_OBJC_TYPE(RTCVideoEncoderSettings) *)settings
+                       numberOfCores:(int)numberOfCores {
+  RTC_DCHECK(settings);
+  RTC_DCHECK([settings.name isEqualToString:kRTCVideoCodecH264Name]);
+
+  _width = settings.width;
+  _height = settings.height;
+  _mode = settings.mode;
+
+  uint32_t aligned_width = (((_width + 15) >> 4) << 4);
+  uint32_t aligned_height = (((_height + 15) >> 4) << 4);
+  _maxAllowedFrameRate = static_cast<uint32_t>(GetMaxSampleRate(*_profile_level_id) /
+                                               (aligned_width * aligned_height));
+
+  // We can only set average bitrate on the HW encoder.
+  _targetBitrateBps = settings.startBitrate * 1000;  // startBitrate is in kbps.
+  _bitrateAdjuster->SetTargetBitrateBps(_targetBitrateBps);
+  _encoderFrameRate = MIN(settings.maxFramerate, _maxAllowedFrameRate);
+  if (settings.maxFramerate > _maxAllowedFrameRate && _maxAllowedFrameRate > 0) {
+    RTC_LOG(LS_WARNING) << "Initial encoder frame rate setting " << settings.maxFramerate
+                        << " is larger than the "
+                        << "maximal allowed frame rate " << _maxAllowedFrameRate << ".";
+  }
+
+  // TODO(tkchin): Try setting payload size via
+  // kVTCompressionPropertyKey_MaxH264SliceBytes.
+
+  return [self resetCompressionSessionWithPixelFormat:kNV12PixelFormat];
+}
+
+- (NSInteger)encode:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame
+    codecSpecificInfo:(nullable id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo
+           frameTypes:(NSArray<NSNumber *> *)frameTypes {
+  if (!_callback || !_compressionSession) {
+    return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
+  }
+  BOOL isKeyframeRequired = NO;
+
+  // Get a pixel buffer from the pool and copy frame data over.
+  if ([self resetCompressionSessionIfNeededWithFrame:frame]) {
+    isKeyframeRequired = YES;
+  }
+
+  CVPixelBufferRef pixelBuffer = nullptr;
+  if ([frame.buffer isKindOfClass:[RTC_OBJC_TYPE(RTCCVPixelBuffer) class]]) {
+    // Native frame buffer
+    RTC_OBJC_TYPE(RTCCVPixelBuffer) *rtcPixelBuffer =
+        (RTC_OBJC_TYPE(RTCCVPixelBuffer) *)frame.buffer;
+    if (![rtcPixelBuffer requiresCropping]) {
+      // This pixel buffer might have a higher resolution than what the
+      // compression session is configured to. The compression session can
+      // handle that and will output encoded frames in the configured
+      // resolution regardless of the input pixel buffer resolution.
+      pixelBuffer = rtcPixelBuffer.pixelBuffer;
+      CVBufferRetain(pixelBuffer);
+    } else {
+      // Cropping required, we need to crop and scale to a new pixel buffer.
+      pixelBuffer = CreatePixelBuffer(_pixelBufferPool);
+      if (!pixelBuffer) {
+        return WEBRTC_VIDEO_CODEC_ERROR;
+      }
+      int dstWidth = CVPixelBufferGetWidth(pixelBuffer);
+      int dstHeight = CVPixelBufferGetHeight(pixelBuffer);
+      if ([rtcPixelBuffer requiresScalingToWidth:dstWidth height:dstHeight]) {
+        int size =
+            [rtcPixelBuffer bufferSizeForCroppingAndScalingToWidth:dstWidth height:dstHeight];
+        _frameScaleBuffer.resize(size);
+      } else {
+        _frameScaleBuffer.clear();
+      }
+      _frameScaleBuffer.shrink_to_fit();
+      if (![rtcPixelBuffer cropAndScaleTo:pixelBuffer withTempBuffer:_frameScaleBuffer.data()]) {
+        CVBufferRelease(pixelBuffer);
+        return WEBRTC_VIDEO_CODEC_ERROR;
+      }
+    }
+  }
+
+  if (!pixelBuffer) {
+    // We did not have a native frame buffer
+    RTC_DCHECK_EQ(frame.width, _width);
+    RTC_DCHECK_EQ(frame.height, _height);
+    pixelBuffer = CreatePixelBuffer(_pixelBufferPool);
+    if (!pixelBuffer) {
+      return WEBRTC_VIDEO_CODEC_ERROR;
+    }
+    RTC_DCHECK(pixelBuffer);
+    if (!CopyVideoFrameToNV12PixelBuffer([frame.buffer toI420], pixelBuffer)) {
+      RTC_LOG(LS_ERROR) << "Failed to copy frame data.";
+      CVBufferRelease(pixelBuffer);
+      return WEBRTC_VIDEO_CODEC_ERROR;
+    }
+  }
+
+  // Check if we need a keyframe.
+  if (!isKeyframeRequired && frameTypes) {
+    for (NSNumber *frameType in frameTypes) {
+      if ((RTCFrameType)frameType.intValue == RTCFrameTypeVideoFrameKey) {
+        isKeyframeRequired = YES;
+        break;
+      }
+    }
+  }
+
+  CMTime presentationTimeStamp = CMTimeMake(frame.timeStampNs / rtc::kNumNanosecsPerMillisec, 1000);
+  CFDictionaryRef frameProperties = nullptr;
+  if (isKeyframeRequired) {
+    CFTypeRef keys[] = {kVTEncodeFrameOptionKey_ForceKeyFrame};
+    CFTypeRef values[] = {kCFBooleanTrue};
+    frameProperties = CreateCFTypeDictionary(keys, values, 1);
+  }
+
+  std::unique_ptr<RTCFrameEncodeParams> encodeParams;
+  encodeParams.reset(new RTCFrameEncodeParams(self,
+                                              codecSpecificInfo,
+                                              _width,
+                                              _height,
+                                              frame.timeStampNs / rtc::kNumNanosecsPerMillisec,
+                                              frame.timeStamp,
+                                              frame.rotation));
+  encodeParams->codecSpecificInfo.packetizationMode = _packetizationMode;
+
+  // Update the bitrate if needed.
+  [self setBitrateBps:_bitrateAdjuster->GetAdjustedBitrateBps() frameRate:_encoderFrameRate];
+
+  OSStatus status = VTCompressionSessionEncodeFrame(_compressionSession,
+                                                    pixelBuffer,
+                                                    presentationTimeStamp,
+                                                    kCMTimeInvalid,
+                                                    frameProperties,
+                                                    encodeParams.release(),
+                                                    nullptr);
+  if (frameProperties) {
+    CFRelease(frameProperties);
+  }
+  if (pixelBuffer) {
+    CVBufferRelease(pixelBuffer);
+  }
+
+  if (status == kVTInvalidSessionErr) {
+    // This error occurs when entering foreground after backgrounding the app.
+    RTC_LOG(LS_ERROR) << "Invalid compression session, resetting.";
+    [self resetCompressionSessionWithPixelFormat:[self pixelFormatOfFrame:frame]];
+
+    return WEBRTC_VIDEO_CODEC_NO_OUTPUT;
+  } else if (status == kVTVideoEncoderMalfunctionErr) {
+    // Sometimes the encoder malfunctions and needs to be restarted.
+    RTC_LOG(LS_ERROR)
+        << "Encountered video encoder malfunction error. Resetting compression session.";
+    [self resetCompressionSessionWithPixelFormat:[self pixelFormatOfFrame:frame]];
+
+    return WEBRTC_VIDEO_CODEC_NO_OUTPUT;
+  } else if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to encode frame with code: " << status;
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (void)setCallback:(RTCVideoEncoderCallback)callback {
+  _callback = callback;
+}
+
+- (int)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate {
+  _targetBitrateBps = 1000 * bitrateKbit;
+  _bitrateAdjuster->SetTargetBitrateBps(_targetBitrateBps);
+  if (framerate > _maxAllowedFrameRate && _maxAllowedFrameRate > 0) {
+    RTC_LOG(LS_WARNING) << "Encoder frame rate setting " << framerate << " is larger than the "
+                        << "maximal allowed frame rate " << _maxAllowedFrameRate << ".";
+  }
+  framerate = MIN(framerate, _maxAllowedFrameRate);
+  [self setBitrateBps:_bitrateAdjuster->GetAdjustedBitrateBps() frameRate:framerate];
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (NSInteger)resolutionAlignment {
+  return 1;
+}
+
+- (BOOL)applyAlignmentToAllSimulcastLayers {
+  return NO;
+}
+
+- (BOOL)supportsNativeHandle {
+  return YES;
+}
+
+#pragma mark - Private
+
+- (NSInteger)releaseEncoder {
+  // Need to destroy so that the session is invalidated and won't use the
+  // callback anymore. Do not remove callback until the session is invalidated
+  // since async encoder callbacks can occur until invalidation.
+  [self destroyCompressionSession];
+  _callback = nullptr;
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (OSType)pixelFormatOfFrame:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame {
+  // Use NV12 for non-native frames.
+  if ([frame.buffer isKindOfClass:[RTC_OBJC_TYPE(RTCCVPixelBuffer) class]]) {
+    RTC_OBJC_TYPE(RTCCVPixelBuffer) *rtcPixelBuffer =
+        (RTC_OBJC_TYPE(RTCCVPixelBuffer) *)frame.buffer;
+    return CVPixelBufferGetPixelFormatType(rtcPixelBuffer.pixelBuffer);
+  }
+
+  return kNV12PixelFormat;
+}
+
+- (BOOL)resetCompressionSessionIfNeededWithFrame:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame {
+  BOOL resetCompressionSession = NO;
+
+  // If we're capturing native frames in another pixel format than the compression session is
+  // configured with, make sure the compression session is reset using the correct pixel format.
+  OSType framePixelFormat = [self pixelFormatOfFrame:frame];
+
+  if (_compressionSession) {
+    // The pool attribute `kCVPixelBufferPixelFormatTypeKey` can contain either an array of pixel
+    // formats or a single pixel format.
+    NSDictionary *poolAttributes =
+        (__bridge NSDictionary *)CVPixelBufferPoolGetPixelBufferAttributes(_pixelBufferPool);
+    id pixelFormats =
+        [poolAttributes objectForKey:(__bridge NSString *)kCVPixelBufferPixelFormatTypeKey];
+    NSArray<NSNumber *> *compressionSessionPixelFormats = nil;
+    if ([pixelFormats isKindOfClass:[NSArray class]]) {
+      compressionSessionPixelFormats = (NSArray *)pixelFormats;
+    } else if ([pixelFormats isKindOfClass:[NSNumber class]]) {
+      compressionSessionPixelFormats = @[ (NSNumber *)pixelFormats ];
+    }
+
+    if (![compressionSessionPixelFormats
+            containsObject:[NSNumber numberWithLong:framePixelFormat]]) {
+      resetCompressionSession = YES;
+      RTC_LOG(LS_INFO) << "Resetting compression session due to non-matching pixel format.";
+    }
+  } else {
+    resetCompressionSession = YES;
+  }
+
+  if (resetCompressionSession) {
+    [self resetCompressionSessionWithPixelFormat:framePixelFormat];
+  }
+  return resetCompressionSession;
+}
+
+- (int)resetCompressionSessionWithPixelFormat:(OSType)framePixelFormat {
+  [self destroyCompressionSession];
+
+  // Set source image buffer attributes. These attributes will be present on
+  // buffers retrieved from the encoder's pixel buffer pool.
+  NSDictionary *sourceAttributes = @{
+#if defined(WEBRTC_IOS) && (TARGET_OS_MACCATALYST || TARGET_OS_SIMULATOR)
+    (NSString *)kCVPixelBufferMetalCompatibilityKey : @(YES),
+#elif defined(WEBRTC_IOS)
+    (NSString *)kCVPixelBufferOpenGLESCompatibilityKey : @(YES),
+#elif defined(WEBRTC_MAC) && !defined(WEBRTC_ARCH_ARM64)
+    (NSString *)kCVPixelBufferOpenGLCompatibilityKey : @(YES),
+#endif
+    (NSString *)kCVPixelBufferIOSurfacePropertiesKey : @{},
+    (NSString *)kCVPixelBufferPixelFormatTypeKey : @(framePixelFormat),
+  };
+
+  NSDictionary *encoder_specs;
+#if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS)
+  // Currently hw accl is supported above 360p on mac, below 360p
+  // the compression session will be created with hw accl disabled.
+  encoder_specs = @{
+    (NSString *)kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder : @(YES),
+  };
+
+#endif
+  OSStatus status = VTCompressionSessionCreate(
+      nullptr,  // use default allocator
+      _width,
+      _height,
+      kCMVideoCodecType_H264,
+      (__bridge CFDictionaryRef)encoder_specs,  // use hardware accelerated encoder if available
+      (__bridge CFDictionaryRef)sourceAttributes,
+      nullptr,  // use default compressed data allocator
+      compressionOutputCallback,
+      nullptr,
+      &_compressionSession);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to create compression session: " << status;
+    return WEBRTC_VIDEO_CODEC_ERROR;
+  }
+#if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS)
+  CFBooleanRef hwaccl_enabled = nullptr;
+  status = VTSessionCopyProperty(_compressionSession,
+                                 kVTCompressionPropertyKey_UsingHardwareAcceleratedVideoEncoder,
+                                 nullptr,
+                                 &hwaccl_enabled);
+  if (status == noErr && (CFBooleanGetValue(hwaccl_enabled))) {
+    RTC_LOG(LS_INFO) << "Compression session created with hw accl enabled";
+  } else {
+    RTC_LOG(LS_INFO) << "Compression session created with hw accl disabled";
+  }
+#endif
+  [self configureCompressionSession];
+
+  // The pixel buffer pool is dependent on the compression session so if the session is reset, the
+  // pool should be reset as well.
+  _pixelBufferPool = VTCompressionSessionGetPixelBufferPool(_compressionSession);
+
+  return WEBRTC_VIDEO_CODEC_OK;
+}
+
+- (void)configureCompressionSession {
+  RTC_DCHECK(_compressionSession);
+  SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_RealTime, true);
+  SetVTSessionProperty(_compressionSession,
+                       kVTCompressionPropertyKey_ProfileLevel,
+                       ExtractProfile(*_profile_level_id));
+  SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AllowFrameReordering, false);
+  [self setEncoderBitrateBps:_targetBitrateBps frameRate:_encoderFrameRate];
+  // TODO(tkchin): Look at entropy mode and colorspace matrices.
+  // TODO(tkchin): Investigate to see if there's any way to make this work.
+  // May need it to interop with Android. Currently this call just fails.
+  // On inspecting encoder output on iOS8, this value is set to 6.
+  // internal::SetVTSessionProperty(compression_session_,
+  //     kVTCompressionPropertyKey_MaxFrameDelayCount,
+  //     1);
+
+  // Set a relatively large value for keyframe emission (7200 frames or 4 minutes).
+  SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_MaxKeyFrameInterval, 7200);
+  SetVTSessionProperty(
+      _compressionSession, kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration, 240);
+}
+
+- (void)destroyCompressionSession {
+  if (_compressionSession) {
+    VTCompressionSessionInvalidate(_compressionSession);
+    CFRelease(_compressionSession);
+    _compressionSession = nullptr;
+    _pixelBufferPool = nullptr;
+  }
+}
+
+- (NSString *)implementationName {
+  return @"VideoToolbox";
+}
+
+- (void)setBitrateBps:(uint32_t)bitrateBps frameRate:(uint32_t)frameRate {
+  if (_encoderBitrateBps != bitrateBps || _encoderFrameRate != frameRate) {
+    [self setEncoderBitrateBps:bitrateBps frameRate:frameRate];
+  }
+}
+
+- (void)setEncoderBitrateBps:(uint32_t)bitrateBps frameRate:(uint32_t)frameRate {
+  if (_compressionSession) {
+    SetVTSessionProperty(_compressionSession, kVTCompressionPropertyKey_AverageBitRate, bitrateBps);
+
+    // With zero `_maxAllowedFrameRate`, we fall back to automatic frame rate detection.
+    if (_maxAllowedFrameRate > 0) {
+      SetVTSessionProperty(
+          _compressionSession, kVTCompressionPropertyKey_ExpectedFrameRate, frameRate);
+    }
+
+    // TODO(tkchin): Add a helper method to set array value.
+    int64_t dataLimitBytesPerSecondValue =
+        static_cast<int64_t>(bitrateBps * kLimitToAverageBitRateFactor / 8);
+    CFNumberRef bytesPerSecond =
+        CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &dataLimitBytesPerSecondValue);
+    int64_t oneSecondValue = 1;
+    CFNumberRef oneSecond =
+        CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &oneSecondValue);
+    const void *nums[2] = {bytesPerSecond, oneSecond};
+    CFArrayRef dataRateLimits = CFArrayCreate(nullptr, nums, 2, &kCFTypeArrayCallBacks);
+    OSStatus status = VTSessionSetProperty(
+        _compressionSession, kVTCompressionPropertyKey_DataRateLimits, dataRateLimits);
+    if (bytesPerSecond) {
+      CFRelease(bytesPerSecond);
+    }
+    if (oneSecond) {
+      CFRelease(oneSecond);
+    }
+    if (dataRateLimits) {
+      CFRelease(dataRateLimits);
+    }
+    if (status != noErr) {
+      RTC_LOG(LS_ERROR) << "Failed to set data rate limit with code: " << status;
+    }
+
+    _encoderBitrateBps = bitrateBps;
+    _encoderFrameRate = frameRate;
+  }
+}
+
+- (void)frameWasEncoded:(OSStatus)status
+                  flags:(VTEncodeInfoFlags)infoFlags
+           sampleBuffer:(CMSampleBufferRef)sampleBuffer
+      codecSpecificInfo:(id<RTC_OBJC_TYPE(RTCCodecSpecificInfo)>)codecSpecificInfo
+                  width:(int32_t)width
+                 height:(int32_t)height
+           renderTimeMs:(int64_t)renderTimeMs
+              timestamp:(uint32_t)timestamp
+               rotation:(RTCVideoRotation)rotation {
+  RTCVideoEncoderCallback callback = _callback;
+  if (!callback) {
+    return;
+  }
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "H264 encode failed with code: " << status;
+    return;
+  }
+  if (infoFlags & kVTEncodeInfo_FrameDropped) {
+    RTC_LOG(LS_INFO) << "H264 encode dropped frame.";
+    return;
+  }
+
+  BOOL isKeyframe = NO;
+  CFArrayRef attachments = CMSampleBufferGetSampleAttachmentsArray(sampleBuffer, 0);
+  if (attachments != nullptr && CFArrayGetCount(attachments)) {
+    CFDictionaryRef attachment =
+        static_cast<CFDictionaryRef>(CFArrayGetValueAtIndex(attachments, 0));
+    isKeyframe = !CFDictionaryContainsKey(attachment, kCMSampleAttachmentKey_NotSync);
+  }
+
+  if (isKeyframe) {
+    RTC_LOG(LS_INFO) << "Generated keyframe";
+  }
+
+  __block std::unique_ptr<rtc::Buffer> buffer = std::make_unique<rtc::Buffer>();
+  if (!webrtc::H264CMSampleBufferToAnnexBBuffer(sampleBuffer, isKeyframe, buffer.get())) {
+    return;
+  }
+
+  RTC_OBJC_TYPE(RTCEncodedImage) *frame = [[RTC_OBJC_TYPE(RTCEncodedImage) alloc] init];
+  // This assumes ownership of `buffer` and is responsible for freeing it when done.
+  frame.buffer = [[NSData alloc] initWithBytesNoCopy:buffer->data()
+                                              length:buffer->size()
+                                         deallocator:^(void *bytes, NSUInteger size) {
+                                           buffer.reset();
+                                         }];
+  frame.encodedWidth = width;
+  frame.encodedHeight = height;
+  frame.frameType = isKeyframe ? RTCFrameTypeVideoFrameKey : RTCFrameTypeVideoFrameDelta;
+  frame.captureTimeMs = renderTimeMs;
+  frame.timeStamp = timestamp;
+  frame.rotation = rotation;
+  frame.contentType = (_mode == RTCVideoCodecModeScreensharing) ? RTCVideoContentTypeScreenshare :
+                                                                  RTCVideoContentTypeUnspecified;
+  frame.flags = webrtc::VideoSendTiming::kInvalid;
+
+  _h264BitstreamParser.ParseBitstream(*buffer);
+  frame.qp = @(_h264BitstreamParser.GetLastSliceQp().value_or(-1));
+
+  BOOL res = callback(frame, codecSpecificInfo);
+  if (!res) {
+    RTC_LOG(LS_ERROR) << "Encode callback failed";
+    return;
+  }
+  _bitrateAdjuster->Update(frame.buffer.length);
+}
+
+- (nullable RTC_OBJC_TYPE(RTCVideoEncoderQpThresholds) *)scalingSettings {
+  return [[RTC_OBJC_TYPE(RTCVideoEncoderQpThresholds) alloc]
+      initWithThresholdsLow:kLowH264QpThreshold
+                       high:kHighH264QpThreshold];
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.h b/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.h
new file mode 100644
index 0000000000..a51debb9fa
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.h
@@ -0,0 +1,19 @@
+/*
+ *  Copyright 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <UIKit/UIKit.h>
+
+#include "api/video_codecs/h264_profile_level_id.h"
+
+@interface UIDevice (H264Profile)
+
++ (absl::optional<webrtc::H264ProfileLevelId>)maxSupportedH264Profile;
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.mm b/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.mm
new file mode 100644
index 0000000000..0ef6a8d77c
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/UIDevice+H264Profile.mm
@@ -0,0 +1,205 @@
+/*
+ *  Copyright 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "UIDevice+H264Profile.h"
+#import "helpers/UIDevice+RTCDevice.h"
+
+#include <algorithm>
+
+namespace {
+
+using namespace webrtc;
+
+struct SupportedH264Profile {
+  const RTCDeviceType deviceType;
+  const H264ProfileLevelId profile;
+};
+
+constexpr SupportedH264Profile kH264MaxSupportedProfiles[] = {
+    // iPhones with at least iOS 9
+    {RTCDeviceTypeIPhone13ProMax,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP848
+    {RTCDeviceTypeIPhone13Pro,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP852
+    {RTCDeviceTypeIPhone13,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP851
+    {RTCDeviceTypeIPhone13Mini,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP847
+    {RTCDeviceTypeIPhoneSE2Gen,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP820
+    {RTCDeviceTypeIPhone12ProMax,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP832
+    {RTCDeviceTypeIPhone12Pro,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP831
+    {RTCDeviceTypeIPhone12,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP830
+    {RTCDeviceTypeIPhone12Mini,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP829
+    {RTCDeviceTypeIPhone11ProMax,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP806
+    {RTCDeviceTypeIPhone11Pro,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP805
+    {RTCDeviceTypeIPhone11,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP804
+    {RTCDeviceTypeIPhoneXS,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP779
+    {RTCDeviceTypeIPhoneXSMax,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP780
+    {RTCDeviceTypeIPhoneXR,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP781
+    {RTCDeviceTypeIPhoneX,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP770
+    {RTCDeviceTypeIPhone8,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP767
+    {RTCDeviceTypeIPhone8Plus,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP768
+    {RTCDeviceTypeIPhone7,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_1}},  // https://support.apple.com/kb/SP743
+    {RTCDeviceTypeIPhone7Plus,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_1}},  // https://support.apple.com/kb/SP744
+    {RTCDeviceTypeIPhoneSE,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP738
+    {RTCDeviceTypeIPhone6S,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP726
+    {RTCDeviceTypeIPhone6SPlus,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP727
+    {RTCDeviceTypeIPhone6,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP705
+    {RTCDeviceTypeIPhone6Plus,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP706
+    {RTCDeviceTypeIPhone5SGSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP685
+    {RTCDeviceTypeIPhone5SGSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP685
+    {RTCDeviceTypeIPhone5GSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP655
+    {RTCDeviceTypeIPhone5GSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP655
+    {RTCDeviceTypeIPhone5CGSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP684
+    {RTCDeviceTypeIPhone5CGSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP684
+    {RTCDeviceTypeIPhone4S,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP643
+
+    // iPods with at least iOS 9
+    {RTCDeviceTypeIPodTouch7G,
+     {H264Profile::kProfileMain, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP796
+    {RTCDeviceTypeIPodTouch6G,
+     {H264Profile::kProfileMain, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP720
+    {RTCDeviceTypeIPodTouch5G,
+     {H264Profile::kProfileMain, H264Level::kLevel3_1}},  // https://support.apple.com/kb/SP657
+
+    // iPads with at least iOS 9
+    {RTCDeviceTypeIPadAir4Gen,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP828
+    {RTCDeviceTypeIPad8,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP822
+    {RTCDeviceTypeIPadPro4Gen12Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP815
+    {RTCDeviceTypeIPadPro4Gen11Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP814
+    {RTCDeviceTypeIPadAir3Gen,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP787
+    {RTCDeviceTypeIPadMini5Gen,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP788
+    {RTCDeviceTypeIPadPro3Gen12Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP785
+    {RTCDeviceTypeIPadPro3Gen11Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP784
+    {RTCDeviceTypeIPad7Gen10Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP807
+    {RTCDeviceTypeIPad2Wifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP622
+    {RTCDeviceTypeIPad2GSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP622
+    {RTCDeviceTypeIPad2CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP622
+    {RTCDeviceTypeIPad2Wifi2,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP622
+    {RTCDeviceTypeIPadMiniWifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP661
+    {RTCDeviceTypeIPadMiniGSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP661
+    {RTCDeviceTypeIPadMiniGSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP661
+    {RTCDeviceTypeIPad3Wifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP647
+    {RTCDeviceTypeIPad3GSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP647
+    {RTCDeviceTypeIPad3GSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP647
+    {RTCDeviceTypeIPad4Wifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP662
+    {RTCDeviceTypeIPad4GSM,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP662
+    {RTCDeviceTypeIPad4GSM_CDMA,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_1}},  // https://support.apple.com/kb/SP662
+    {RTCDeviceTypeIPad5,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP751
+    {RTCDeviceTypeIPad6,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP774
+    {RTCDeviceTypeIPadAirWifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP692
+    {RTCDeviceTypeIPadAirCellular,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP692
+    {RTCDeviceTypeIPadAirWifiCellular,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP692
+    {RTCDeviceTypeIPadAir2,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP708
+    {RTCDeviceTypeIPadMini2GWifi,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP693
+    {RTCDeviceTypeIPadMini2GCellular,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP693
+    {RTCDeviceTypeIPadMini2GWifiCellular,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP693
+    {RTCDeviceTypeIPadMini3,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP709
+    {RTCDeviceTypeIPadMini4,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP725
+    {RTCDeviceTypeIPadPro9Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP739
+    {RTCDeviceTypeIPadPro12Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/sp723
+    {RTCDeviceTypeIPadPro12Inch2,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP761
+    {RTCDeviceTypeIPadPro10Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP762
+    {RTCDeviceTypeIPadMini6,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP850
+    {RTCDeviceTypeIPad9,
+     {H264Profile::kProfileHigh, H264Level::kLevel4_2}},  // https://support.apple.com/kb/SP849
+    {RTCDeviceTypeIPadPro5Gen12Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP844
+    {RTCDeviceTypeIPadPro5Gen11Inch,
+     {H264Profile::kProfileHigh, H264Level::kLevel5_2}},  // https://support.apple.com/kb/SP843
+};
+
+absl::optional<H264ProfileLevelId> FindMaxSupportedProfileForDevice(RTCDeviceType deviceType) {
+  const auto* result = std::find_if(std::begin(kH264MaxSupportedProfiles),
+                                    std::end(kH264MaxSupportedProfiles),
+                                    [deviceType](const SupportedH264Profile& supportedProfile) {
+                                      return supportedProfile.deviceType == deviceType;
+                                    });
+  if (result != std::end(kH264MaxSupportedProfiles)) {
+    return result->profile;
+  }
+  return absl::nullopt;
+}
+
+}  // namespace
+
+@implementation UIDevice (H264Profile)
+
++ (absl::optional<webrtc::H264ProfileLevelId>)maxSupportedH264Profile {
+  return FindMaxSupportedProfileForDevice([self deviceType]);
+}
+
+@end
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.cc b/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.cc
new file mode 100644
index 0000000000..ac957f1b49
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.cc
@@ -0,0 +1,90 @@
+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#include "helpers.h"
+
+#include <string>
+
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+
+// Copies characters from a CFStringRef into a std::string.
+std::string CFStringToString(const CFStringRef cf_string) {
+  RTC_DCHECK(cf_string);
+  std::string std_string;
+  // Get the size needed for UTF8 plus terminating character.
+  size_t buffer_size =
+      CFStringGetMaximumSizeForEncoding(CFStringGetLength(cf_string),
+                                        kCFStringEncodingUTF8) +
+      1;
+  std::unique_ptr<char[]> buffer(new char[buffer_size]);
+  if (CFStringGetCString(cf_string, buffer.get(), buffer_size,
+                         kCFStringEncodingUTF8)) {
+    // Copy over the characters.
+    std_string.assign(buffer.get());
+  }
+  return std_string;
+}
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session,
+                          CFStringRef key,
+                          int32_t value) {
+  CFNumberRef cfNum =
+      CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &value);
+  OSStatus status = VTSessionSetProperty(session, key, cfNum);
+  CFRelease(cfNum);
+  if (status != noErr) {
+    std::string key_string = CFStringToString(key);
+    RTC_LOG(LS_ERROR) << "VTSessionSetProperty failed to set: " << key_string
+                      << " to " << value << ": " << status;
+  }
+}
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session,
+                          CFStringRef key,
+                          uint32_t value) {
+  int64_t value_64 = value;
+  CFNumberRef cfNum =
+      CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &value_64);
+  OSStatus status = VTSessionSetProperty(session, key, cfNum);
+  CFRelease(cfNum);
+  if (status != noErr) {
+    std::string key_string = CFStringToString(key);
+    RTC_LOG(LS_ERROR) << "VTSessionSetProperty failed to set: " << key_string
+                      << " to " << value << ": " << status;
+  }
+}
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session, CFStringRef key, bool value) {
+  CFBooleanRef cf_bool = (value) ? kCFBooleanTrue : kCFBooleanFalse;
+  OSStatus status = VTSessionSetProperty(session, key, cf_bool);
+  if (status != noErr) {
+    std::string key_string = CFStringToString(key);
+    RTC_LOG(LS_ERROR) << "VTSessionSetProperty failed to set: " << key_string
+                      << " to " << value << ": " << status;
+  }
+}
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session,
+                          CFStringRef key,
+                          CFStringRef value) {
+  OSStatus status = VTSessionSetProperty(session, key, value);
+  if (status != noErr) {
+    std::string key_string = CFStringToString(key);
+    std::string val_string = CFStringToString(value);
+    RTC_LOG(LS_ERROR) << "VTSessionSetProperty failed to set: " << key_string
+                      << " to " << val_string << ": " << status;
+  }
+}
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.h b/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.h
new file mode 100644
index 0000000000..7c9ef1cd87
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/helpers.h
@@ -0,0 +1,47 @@
+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#ifndef SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_HELPERS_H_
+#define SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_HELPERS_H_
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <VideoToolbox/VideoToolbox.h>
+#include <string>
+
+// Convenience function for creating a dictionary.
+inline CFDictionaryRef CreateCFTypeDictionary(CFTypeRef* keys,
+                                              CFTypeRef* values,
+                                              size_t size) {
+  return CFDictionaryCreate(kCFAllocatorDefault, keys, values, size,
+                            &kCFTypeDictionaryKeyCallBacks,
+                            &kCFTypeDictionaryValueCallBacks);
+}
+
+// Copies characters from a CFStringRef into a std::string.
+std::string CFStringToString(CFStringRef cf_string);
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session, CFStringRef key, int32_t value);
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session,
+                          CFStringRef key,
+                          uint32_t value);
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session, CFStringRef key, bool value);
+
+// Convenience function for setting a VT property.
+void SetVTSessionProperty(VTSessionRef session,
+                          CFStringRef key,
+                          CFStringRef value);
+
+#endif  // SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_HELPERS_H_
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.cc b/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.cc
new file mode 100644
index 0000000000..b7330e1f9c
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.cc
@@ -0,0 +1,327 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#include "sdk/objc/components/video_codec/nalu_rewriter.h"
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <memory>
+#include <vector>
+
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+
+namespace webrtc {
+
+using H264::kAud;
+using H264::kSps;
+using H264::NaluIndex;
+using H264::NaluType;
+using H264::ParseNaluType;
+
+const char kAnnexBHeaderBytes[4] = {0, 0, 0, 1};
+const size_t kAvccHeaderByteSize = sizeof(uint32_t);
+
+bool H264CMSampleBufferToAnnexBBuffer(CMSampleBufferRef avcc_sample_buffer,
+                                      bool is_keyframe,
+                                      rtc::Buffer* annexb_buffer) {
+  RTC_DCHECK(avcc_sample_buffer);
+
+  // Get format description from the sample buffer.
+  CMVideoFormatDescriptionRef description =
+      CMSampleBufferGetFormatDescription(avcc_sample_buffer);
+  if (description == nullptr) {
+    RTC_LOG(LS_ERROR) << "Failed to get sample buffer's description.";
+    return false;
+  }
+
+  // Get parameter set information.
+  int nalu_header_size = 0;
+  size_t param_set_count = 0;
+  OSStatus status = CMVideoFormatDescriptionGetH264ParameterSetAtIndex(
+      description, 0, nullptr, nullptr, &param_set_count, &nalu_header_size);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to get parameter set.";
+    return false;
+  }
+  RTC_CHECK_EQ(nalu_header_size, kAvccHeaderByteSize);
+  RTC_DCHECK_EQ(param_set_count, 2);
+
+  // Truncate any previous data in the buffer without changing its capacity.
+  annexb_buffer->SetSize(0);
+
+  // Place all parameter sets at the front of buffer.
+  if (is_keyframe) {
+    size_t param_set_size = 0;
+    const uint8_t* param_set = nullptr;
+    for (size_t i = 0; i < param_set_count; ++i) {
+      status = CMVideoFormatDescriptionGetH264ParameterSetAtIndex(
+          description, i, &param_set, &param_set_size, nullptr, nullptr);
+      if (status != noErr) {
+        RTC_LOG(LS_ERROR) << "Failed to get parameter set.";
+        return false;
+      }
+      // Update buffer.
+      annexb_buffer->AppendData(kAnnexBHeaderBytes, sizeof(kAnnexBHeaderBytes));
+      annexb_buffer->AppendData(reinterpret_cast<const char*>(param_set),
+                                param_set_size);
+    }
+  }
+
+  // Get block buffer from the sample buffer.
+  CMBlockBufferRef block_buffer =
+      CMSampleBufferGetDataBuffer(avcc_sample_buffer);
+  if (block_buffer == nullptr) {
+    RTC_LOG(LS_ERROR) << "Failed to get sample buffer's block buffer.";
+    return false;
+  }
+  CMBlockBufferRef contiguous_buffer = nullptr;
+  // Make sure block buffer is contiguous.
+  if (!CMBlockBufferIsRangeContiguous(block_buffer, 0, 0)) {
+    status = CMBlockBufferCreateContiguous(
+        nullptr, block_buffer, nullptr, nullptr, 0, 0, 0, &contiguous_buffer);
+    if (status != noErr) {
+      RTC_LOG(LS_ERROR) << "Failed to flatten non-contiguous block buffer: "
+                        << status;
+      return false;
+    }
+  } else {
+    contiguous_buffer = block_buffer;
+    // Retain to make cleanup easier.
+    CFRetain(contiguous_buffer);
+    block_buffer = nullptr;
+  }
+
+  // Now copy the actual data.
+  char* data_ptr = nullptr;
+  size_t block_buffer_size = CMBlockBufferGetDataLength(contiguous_buffer);
+  status = CMBlockBufferGetDataPointer(contiguous_buffer, 0, nullptr, nullptr,
+                                       &data_ptr);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to get block buffer data.";
+    CFRelease(contiguous_buffer);
+    return false;
+  }
+  size_t bytes_remaining = block_buffer_size;
+  while (bytes_remaining > 0) {
+    // The size type here must match `nalu_header_size`, we expect 4 bytes.
+    // Read the length of the next packet of data. Must convert from big endian
+    // to host endian.
+    RTC_DCHECK_GE(bytes_remaining, (size_t)nalu_header_size);
+    uint32_t* uint32_data_ptr = reinterpret_cast<uint32_t*>(data_ptr);
+    uint32_t packet_size = CFSwapInt32BigToHost(*uint32_data_ptr);
+    // Update buffer.
+    annexb_buffer->AppendData(kAnnexBHeaderBytes, sizeof(kAnnexBHeaderBytes));
+    annexb_buffer->AppendData(data_ptr + nalu_header_size, packet_size);
+
+    size_t bytes_written = packet_size + sizeof(kAnnexBHeaderBytes);
+    bytes_remaining -= bytes_written;
+    data_ptr += bytes_written;
+  }
+  RTC_DCHECK_EQ(bytes_remaining, (size_t)0);
+
+  CFRelease(contiguous_buffer);
+  return true;
+}
+
+bool H264AnnexBBufferToCMSampleBuffer(const uint8_t* annexb_buffer,
+                                      size_t annexb_buffer_size,
+                                      CMVideoFormatDescriptionRef video_format,
+                                      CMSampleBufferRef* out_sample_buffer,
+                                      CMMemoryPoolRef memory_pool) {
+  RTC_DCHECK(annexb_buffer);
+  RTC_DCHECK(out_sample_buffer);
+  RTC_DCHECK(video_format);
+  *out_sample_buffer = nullptr;
+
+  AnnexBBufferReader reader(annexb_buffer, annexb_buffer_size);
+  if (reader.SeekToNextNaluOfType(kSps)) {
+    // Buffer contains an SPS NALU - skip it and the following PPS
+    const uint8_t* data;
+    size_t data_len;
+    if (!reader.ReadNalu(&data, &data_len)) {
+      RTC_LOG(LS_ERROR) << "Failed to read SPS";
+      return false;
+    }
+    if (!reader.ReadNalu(&data, &data_len)) {
+      RTC_LOG(LS_ERROR) << "Failed to read PPS";
+      return false;
+    }
+  } else {
+    // No SPS NALU - start reading from the first NALU in the buffer
+    reader.SeekToStart();
+  }
+
+  // Allocate memory as a block buffer.
+  CMBlockBufferRef block_buffer = nullptr;
+  CFAllocatorRef block_allocator = CMMemoryPoolGetAllocator(memory_pool);
+  OSStatus status = CMBlockBufferCreateWithMemoryBlock(
+      kCFAllocatorDefault, nullptr, reader.BytesRemaining(), block_allocator,
+      nullptr, 0, reader.BytesRemaining(), kCMBlockBufferAssureMemoryNowFlag,
+      &block_buffer);
+  if (status != kCMBlockBufferNoErr) {
+    RTC_LOG(LS_ERROR) << "Failed to create block buffer.";
+    return false;
+  }
+
+  // Make sure block buffer is contiguous.
+  CMBlockBufferRef contiguous_buffer = nullptr;
+  if (!CMBlockBufferIsRangeContiguous(block_buffer, 0, 0)) {
+    status = CMBlockBufferCreateContiguous(kCFAllocatorDefault, block_buffer,
+                                           block_allocator, nullptr, 0, 0, 0,
+                                           &contiguous_buffer);
+    if (status != noErr) {
+      RTC_LOG(LS_ERROR) << "Failed to flatten non-contiguous block buffer: "
+                        << status;
+      CFRelease(block_buffer);
+      return false;
+    }
+  } else {
+    contiguous_buffer = block_buffer;
+    block_buffer = nullptr;
+  }
+
+  // Get a raw pointer into allocated memory.
+  size_t block_buffer_size = 0;
+  char* data_ptr = nullptr;
+  status = CMBlockBufferGetDataPointer(contiguous_buffer, 0, nullptr,
+                                       &block_buffer_size, &data_ptr);
+  if (status != kCMBlockBufferNoErr) {
+    RTC_LOG(LS_ERROR) << "Failed to get block buffer data pointer.";
+    CFRelease(contiguous_buffer);
+    return false;
+  }
+  RTC_DCHECK(block_buffer_size == reader.BytesRemaining());
+
+  // Write Avcc NALUs into block buffer memory.
+  AvccBufferWriter writer(reinterpret_cast<uint8_t*>(data_ptr),
+                          block_buffer_size);
+  while (reader.BytesRemaining() > 0) {
+    const uint8_t* nalu_data_ptr = nullptr;
+    size_t nalu_data_size = 0;
+    if (reader.ReadNalu(&nalu_data_ptr, &nalu_data_size)) {
+      writer.WriteNalu(nalu_data_ptr, nalu_data_size);
+    }
+  }
+
+  // Create sample buffer.
+  status = CMSampleBufferCreate(kCFAllocatorDefault, contiguous_buffer, true,
+                                nullptr, nullptr, video_format, 1, 0, nullptr,
+                                0, nullptr, out_sample_buffer);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to create sample buffer.";
+    CFRelease(contiguous_buffer);
+    return false;
+  }
+  CFRelease(contiguous_buffer);
+  return true;
+}
+
+CMVideoFormatDescriptionRef CreateVideoFormatDescription(
+    const uint8_t* annexb_buffer,
+    size_t annexb_buffer_size) {
+  const uint8_t* param_set_ptrs[2] = {};
+  size_t param_set_sizes[2] = {};
+  AnnexBBufferReader reader(annexb_buffer, annexb_buffer_size);
+  // Skip everyting before the SPS, then read the SPS and PPS
+  if (!reader.SeekToNextNaluOfType(kSps)) {
+    return nullptr;
+  }
+  if (!reader.ReadNalu(&param_set_ptrs[0], &param_set_sizes[0])) {
+    RTC_LOG(LS_ERROR) << "Failed to read SPS";
+    return nullptr;
+  }
+  if (!reader.ReadNalu(&param_set_ptrs[1], &param_set_sizes[1])) {
+    RTC_LOG(LS_ERROR) << "Failed to read PPS";
+    return nullptr;
+  }
+
+  // Parse the SPS and PPS into a CMVideoFormatDescription.
+  CMVideoFormatDescriptionRef description = nullptr;
+  OSStatus status = CMVideoFormatDescriptionCreateFromH264ParameterSets(
+      kCFAllocatorDefault, 2, param_set_ptrs, param_set_sizes, 4, &description);
+  if (status != noErr) {
+    RTC_LOG(LS_ERROR) << "Failed to create video format description.";
+    return nullptr;
+  }
+  return description;
+}
+
+AnnexBBufferReader::AnnexBBufferReader(const uint8_t* annexb_buffer,
+                                       size_t length)
+    : start_(annexb_buffer), length_(length) {
+  RTC_DCHECK(annexb_buffer);
+  offsets_ = H264::FindNaluIndices(annexb_buffer, length);
+  offset_ = offsets_.begin();
+}
+
+AnnexBBufferReader::~AnnexBBufferReader() = default;
+
+bool AnnexBBufferReader::ReadNalu(const uint8_t** out_nalu,
+                                  size_t* out_length) {
+  RTC_DCHECK(out_nalu);
+  RTC_DCHECK(out_length);
+  *out_nalu = nullptr;
+  *out_length = 0;
+
+  if (offset_ == offsets_.end()) {
+    return false;
+  }
+  *out_nalu = start_ + offset_->payload_start_offset;
+  *out_length = offset_->payload_size;
+  ++offset_;
+  return true;
+}
+
+size_t AnnexBBufferReader::BytesRemaining() const {
+  if (offset_ == offsets_.end()) {
+    return 0;
+  }
+  return length_ - offset_->start_offset;
+}
+
+void AnnexBBufferReader::SeekToStart() {
+  offset_ = offsets_.begin();
+}
+
+bool AnnexBBufferReader::SeekToNextNaluOfType(NaluType type) {
+  for (; offset_ != offsets_.end(); ++offset_) {
+    if (offset_->payload_size < 1)
+      continue;
+    if (ParseNaluType(*(start_ + offset_->payload_start_offset)) == type)
+      return true;
+  }
+  return false;
+}
+AvccBufferWriter::AvccBufferWriter(uint8_t* const avcc_buffer, size_t length)
+    : start_(avcc_buffer), offset_(0), length_(length) {
+  RTC_DCHECK(avcc_buffer);
+}
+
+bool AvccBufferWriter::WriteNalu(const uint8_t* data, size_t data_size) {
+  // Check if we can write this length of data.
+  if (data_size + kAvccHeaderByteSize > BytesRemaining()) {
+    return false;
+  }
+  // Write length header, which needs to be big endian.
+  uint32_t big_endian_length = CFSwapInt32HostToBig(data_size);
+  memcpy(start_ + offset_, &big_endian_length, sizeof(big_endian_length));
+  offset_ += sizeof(big_endian_length);
+  // Write data.
+  memcpy(start_ + offset_, data, data_size);
+  offset_ += data_size;
+  return true;
+}
+
+size_t AvccBufferWriter::BytesRemaining() const {
+  return length_ - offset_;
+}
+
+}  // namespace webrtc
diff --git a/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.h b/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.h
new file mode 100644
index 0000000000..c6474971e2
--- /dev/null
+++ b/third_party/libwebrtc/sdk/objc/components/video_codec/nalu_rewriter.h
@@ -0,0 +1,113 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#ifndef SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_NALU_REWRITER_H_
+#define SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_NALU_REWRITER_H_
+
+#include "modules/video_coding/codecs/h264/include/h264.h"
+
+#include <CoreMedia/CoreMedia.h>
+#include <vector>
+
+#include "common_video/h264/h264_common.h"
+#include "rtc_base/buffer.h"
+
+using webrtc::H264::NaluIndex;
+
+namespace webrtc {
+
+// Converts a sample buffer emitted from the VideoToolbox encoder into a buffer
+// suitable for RTP. The sample buffer is in avcc format whereas the rtp buffer
+// needs to be in Annex B format. Data is written directly to `annexb_buffer`.
+bool H264CMSampleBufferToAnnexBBuffer(CMSampleBufferRef avcc_sample_buffer,
+                                      bool is_keyframe,
+                                      rtc::Buffer* annexb_buffer);
+
+// Converts a buffer received from RTP into a sample buffer suitable for the
+// VideoToolbox decoder. The RTP buffer is in annex b format whereas the sample
+// buffer is in avcc format.
+// If `is_keyframe` is true then `video_format` is ignored since the format will
+// be read from the buffer. Otherwise `video_format` must be provided.
+// Caller is responsible for releasing the created sample buffer.
+bool H264AnnexBBufferToCMSampleBuffer(const uint8_t* annexb_buffer,
+                                      size_t annexb_buffer_size,
+                                      CMVideoFormatDescriptionRef video_format,
+                                      CMSampleBufferRef* out_sample_buffer,
+                                      CMMemoryPoolRef memory_pool);
+
+// Returns a video format description created from the sps/pps information in
+// the Annex B buffer. If there is no such information, nullptr is returned.
+// The caller is responsible for releasing the description.
+CMVideoFormatDescriptionRef CreateVideoFormatDescription(
+    const uint8_t* annexb_buffer,
+    size_t annexb_buffer_size);
+
+// Helper class for reading NALUs from an RTP Annex B buffer.
+class AnnexBBufferReader final {
+ public:
+  AnnexBBufferReader(const uint8_t* annexb_buffer, size_t length);
+  ~AnnexBBufferReader();
+  AnnexBBufferReader(const AnnexBBufferReader& other) = delete;
+  void operator=(const AnnexBBufferReader& other) = delete;
+
+  // Returns a pointer to the beginning of the next NALU slice without the
+  // header bytes and its length. Returns false if no more slices remain.
+  bool ReadNalu(const uint8_t** out_nalu, size_t* out_length);
+
+  // Returns the number of unread NALU bytes, including the size of the header.
+  // If the buffer has no remaining NALUs this will return zero.
+  size_t BytesRemaining() const;
+
+  // Reset the reader to start reading from the first NALU
+  void SeekToStart();
+
+  // Seek to the next position that holds a NALU of the desired type,
+  // or the end if no such NALU is found.
+  // Return true if a NALU of the desired type is found, false if we
+  // reached the end instead
+  bool SeekToNextNaluOfType(H264::NaluType type);
+
+ private:
+  // Returns the the next offset that contains NALU data.
+  size_t FindNextNaluHeader(const uint8_t* start,
+                            size_t length,
+                            size_t offset) const;
+
+  const uint8_t* const start_;
+  std::vector<NaluIndex> offsets_;
+  std::vector<NaluIndex>::iterator offset_;
+  const size_t length_;
+};
+
+// Helper class for writing NALUs using avcc format into a buffer.
+class AvccBufferWriter final {
+ public:
+  AvccBufferWriter(uint8_t* const avcc_buffer, size_t length);
+  ~AvccBufferWriter() {}
+  AvccBufferWriter(const AvccBufferWriter& other) = delete;
+  void operator=(const AvccBufferWriter& other) = delete;
+
+  // Writes the data slice into the buffer. Returns false if there isn't
+  // enough space left.
+  bool WriteNalu(const uint8_t* data, size_t data_size);
+
+  // Returns the unused bytes in the buffer.
+  size_t BytesRemaining() const;
+
+ private:
+  uint8_t* const start_;
+  size_t offset_;
+  const size_t length_;
+};
+
+}  // namespace webrtc
+
+#endif  // SDK_OBJC_FRAMEWORK_CLASSES_VIDEOTOOLBOX_NALU_REWRITER_H_