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diff --git a/third_party/libwebrtc/common_video/h264/sps_vui_rewriter.h b/third_party/libwebrtc/common_video/h264/sps_vui_rewriter.h
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+++ b/third_party/libwebrtc/common_video/h264/sps_vui_rewriter.h
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+/*
+ *  Copyright (c) 2016 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 COMMON_VIDEO_H264_SPS_VUI_REWRITER_H_
+#define COMMON_VIDEO_H264_SPS_VUI_REWRITER_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "absl/types/optional.h"
+#include "api/video/color_space.h"
+#include "common_video/h264/sps_parser.h"
+#include "rtc_base/buffer.h"
+
+namespace webrtc {
+
+// A class that can parse an SPS+VUI and if necessary creates a copy with
+// updated parameters.
+// The rewriter disables frame buffering. This should force decoders to deliver
+// decoded frame immediately and, thus, reduce latency.
+// The rewriter updates video signal type parameters if external parameters are
+// provided.
+class SpsVuiRewriter : private SpsParser {
+ public:
+  enum class ParseResult { kFailure, kVuiOk, kVuiRewritten };
+  enum class Direction { kIncoming, kOutgoing };
+
+  // Parses an SPS block and if necessary copies it and rewrites the VUI.
+  // Returns kFailure on failure, kParseOk if parsing succeeded and no update
+  // was necessary and kParsedAndModified if an updated copy of buffer was
+  // written to destination. destination may be populated with some data even if
+  // no rewrite was necessary, but the end offset should remain unchanged.
+  // Unless parsing fails, the sps parameter will be populated with the parsed
+  // SPS state. This function assumes that any previous headers
+  // (NALU start, type, Stap-A, etc) have already been parsed and that RBSP
+  // decoding has been performed.
+  static ParseResult ParseAndRewriteSps(
+      const uint8_t* buffer,
+      size_t length,
+      absl::optional<SpsParser::SpsState>* sps,
+      const ColorSpace* color_space,
+      rtc::Buffer* destination,
+      Direction Direction);
+
+  // Parses NAL units from `buffer`, strips AUD blocks and rewrites VUI in SPS
+  // blocks if necessary.
+  static rtc::Buffer ParseOutgoingBitstreamAndRewrite(
+      rtc::ArrayView<const uint8_t> buffer,
+      const ColorSpace* color_space);
+
+ private:
+  static ParseResult ParseAndRewriteSps(
+      const uint8_t* buffer,
+      size_t length,
+      absl::optional<SpsParser::SpsState>* sps,
+      const ColorSpace* color_space,
+      rtc::Buffer* destination);
+
+  static void UpdateStats(ParseResult result, Direction direction);
+};
+
+}  // namespace webrtc
+
+#endif  // COMMON_VIDEO_H264_SPS_VUI_REWRITER_H_