1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
|
/*
* 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 "RTCCameraVideoCapturer.h"
#import "base/RTCLogging.h"
#import "base/RTCVideoFrameBuffer.h"
#import "components/video_frame_buffer/RTCCVPixelBuffer.h"
#if TARGET_OS_IPHONE
#import "helpers/UIDevice+RTCDevice.h"
#endif
#import "helpers/AVCaptureSession+DevicePosition.h"
#import "helpers/RTCDispatcher+Private.h"
#include "rtc_base/system/gcd_helpers.h"
const int64_t kNanosecondsPerSecond = 1000000000;
@interface RTC_OBJC_TYPE (RTCCameraVideoCapturer)
()<AVCaptureVideoDataOutputSampleBufferDelegate> @property(nonatomic,
readonly) dispatch_queue_t frameQueue;
@property(nonatomic, strong) AVCaptureDevice *currentDevice;
@property(nonatomic, assign) BOOL hasRetriedOnFatalError;
@property(nonatomic, assign) BOOL isRunning;
// Will the session be running once all asynchronous operations have been completed?
@property(nonatomic, assign) BOOL willBeRunning;
@end
@implementation RTC_OBJC_TYPE (RTCCameraVideoCapturer) {
AVCaptureVideoDataOutput *_videoDataOutput;
AVCaptureSession *_captureSession;
FourCharCode _preferredOutputPixelFormat;
FourCharCode _outputPixelFormat;
RTCVideoRotation _rotation;
#if TARGET_OS_IPHONE
UIDeviceOrientation _orientation;
BOOL _generatingOrientationNotifications;
#endif
}
@synthesize frameQueue = _frameQueue;
@synthesize captureSession = _captureSession;
@synthesize currentDevice = _currentDevice;
@synthesize hasRetriedOnFatalError = _hasRetriedOnFatalError;
@synthesize isRunning = _isRunning;
@synthesize willBeRunning = _willBeRunning;
- (instancetype)init {
return [self initWithDelegate:nil captureSession:[[AVCaptureSession alloc] init]];
}
- (instancetype)initWithDelegate:(__weak id<RTC_OBJC_TYPE(RTCVideoCapturerDelegate)>)delegate {
return [self initWithDelegate:delegate captureSession:[[AVCaptureSession alloc] init]];
}
// This initializer is used for testing.
- (instancetype)initWithDelegate:(__weak id<RTC_OBJC_TYPE(RTCVideoCapturerDelegate)>)delegate
captureSession:(AVCaptureSession *)captureSession {
if (self = [super initWithDelegate:delegate]) {
// Create the capture session and all relevant inputs and outputs. We need
// to do this in init because the application may want the capture session
// before we start the capturer for e.g. AVCapturePreviewLayer. All objects
// created here are retained until dealloc and never recreated.
if (![self setupCaptureSession:captureSession]) {
return nil;
}
NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
#if TARGET_OS_IPHONE
_orientation = UIDeviceOrientationPortrait;
_rotation = RTCVideoRotation_90;
[center addObserver:self
selector:@selector(deviceOrientationDidChange:)
name:UIDeviceOrientationDidChangeNotification
object:nil];
[center addObserver:self
selector:@selector(handleCaptureSessionInterruption:)
name:AVCaptureSessionWasInterruptedNotification
object:_captureSession];
[center addObserver:self
selector:@selector(handleCaptureSessionInterruptionEnded:)
name:AVCaptureSessionInterruptionEndedNotification
object:_captureSession];
[center addObserver:self
selector:@selector(handleApplicationDidBecomeActive:)
name:UIApplicationDidBecomeActiveNotification
object:[UIApplication sharedApplication]];
#endif
[center addObserver:self
selector:@selector(handleCaptureSessionRuntimeError:)
name:AVCaptureSessionRuntimeErrorNotification
object:_captureSession];
[center addObserver:self
selector:@selector(handleCaptureSessionDidStartRunning:)
name:AVCaptureSessionDidStartRunningNotification
object:_captureSession];
[center addObserver:self
selector:@selector(handleCaptureSessionDidStopRunning:)
name:AVCaptureSessionDidStopRunningNotification
object:_captureSession];
}
return self;
}
- (void)dealloc {
NSAssert(!_willBeRunning,
@"Session was still running in RTC_OBJC_TYPE(RTCCameraVideoCapturer) dealloc. Forgot to "
@"call stopCapture?");
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
+ (NSArray<AVCaptureDevice *> *)captureDevices {
#if defined(WEBRTC_IOS) && defined(__IPHONE_10_0) && \
__IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_10_0
AVCaptureDeviceDiscoverySession *session = [AVCaptureDeviceDiscoverySession
discoverySessionWithDeviceTypes:@[ AVCaptureDeviceTypeBuiltInWideAngleCamera ]
mediaType:AVMediaTypeVideo
position:AVCaptureDevicePositionUnspecified];
return session.devices;
#else
return [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
#endif
}
+ (NSArray<AVCaptureDeviceFormat *> *)supportedFormatsForDevice:(AVCaptureDevice *)device {
// Support opening the device in any format. We make sure it's converted to a format we
// can handle, if needed, in the method `-setupVideoDataOutput`.
return device.formats;
}
- (FourCharCode)preferredOutputPixelFormat {
return _preferredOutputPixelFormat;
}
- (void)startCaptureWithDevice:(AVCaptureDevice *)device
format:(AVCaptureDeviceFormat *)format
fps:(NSInteger)fps {
[self startCaptureWithDevice:device format:format fps:fps completionHandler:nil];
}
- (void)stopCapture {
[self stopCaptureWithCompletionHandler:nil];
}
- (void)startCaptureWithDevice:(AVCaptureDevice *)device
format:(AVCaptureDeviceFormat *)format
fps:(NSInteger)fps
completionHandler:(nullable void (^)(NSError *_Nullable error))completionHandler {
_willBeRunning = YES;
[RTC_OBJC_TYPE(RTCDispatcher)
dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
RTCLogInfo("startCaptureWithDevice %@ @ %ld fps", format, (long)fps);
#if TARGET_OS_IPHONE
dispatch_async(dispatch_get_main_queue(), ^{
if (!self->_generatingOrientationNotifications) {
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
self->_generatingOrientationNotifications = YES;
}
});
#endif
self.currentDevice = device;
NSError *error = nil;
if (![self.currentDevice lockForConfiguration:&error]) {
RTCLogError(@"Failed to lock device %@. Error: %@",
self.currentDevice,
error.userInfo);
if (completionHandler) {
completionHandler(error);
}
self.willBeRunning = NO;
return;
}
[self reconfigureCaptureSessionInput];
[self updateOrientation];
[self updateDeviceCaptureFormat:format fps:fps];
[self updateVideoDataOutputPixelFormat:format];
[self.captureSession startRunning];
[self.currentDevice unlockForConfiguration];
self.isRunning = YES;
if (completionHandler) {
completionHandler(nil);
}
}];
}
- (void)stopCaptureWithCompletionHandler:(nullable void (^)(void))completionHandler {
_willBeRunning = NO;
[RTC_OBJC_TYPE(RTCDispatcher)
dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
RTCLogInfo("Stop");
self.currentDevice = nil;
for (AVCaptureDeviceInput *oldInput in [self.captureSession.inputs copy]) {
[self.captureSession removeInput:oldInput];
}
[self.captureSession stopRunning];
#if TARGET_OS_IPHONE
dispatch_async(dispatch_get_main_queue(), ^{
if (self->_generatingOrientationNotifications) {
[[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
self->_generatingOrientationNotifications = NO;
}
});
#endif
self.isRunning = NO;
if (completionHandler) {
completionHandler();
}
}];
}
#pragma mark iOS notifications
#if TARGET_OS_IPHONE
- (void)deviceOrientationDidChange:(NSNotification *)notification {
[RTC_OBJC_TYPE(RTCDispatcher) dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
[self updateOrientation];
}];
}
#endif
#pragma mark AVCaptureVideoDataOutputSampleBufferDelegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
fromConnection:(AVCaptureConnection *)connection {
NSParameterAssert(captureOutput == _videoDataOutput);
if (CMSampleBufferGetNumSamples(sampleBuffer) != 1 || !CMSampleBufferIsValid(sampleBuffer) ||
!CMSampleBufferDataIsReady(sampleBuffer)) {
return;
}
CVPixelBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
if (pixelBuffer == nil) {
return;
}
#if TARGET_OS_IPHONE
// Default to portrait orientation on iPhone.
BOOL usingFrontCamera = NO;
// Check the image's EXIF for the camera the image came from as the image could have been
// delayed as we set alwaysDiscardsLateVideoFrames to NO.
AVCaptureDevicePosition cameraPosition =
[AVCaptureSession devicePositionForSampleBuffer:sampleBuffer];
if (cameraPosition != AVCaptureDevicePositionUnspecified) {
usingFrontCamera = AVCaptureDevicePositionFront == cameraPosition;
} else {
AVCaptureDeviceInput *deviceInput =
(AVCaptureDeviceInput *)((AVCaptureInputPort *)connection.inputPorts.firstObject).input;
usingFrontCamera = AVCaptureDevicePositionFront == deviceInput.device.position;
}
switch (_orientation) {
case UIDeviceOrientationPortrait:
_rotation = RTCVideoRotation_90;
break;
case UIDeviceOrientationPortraitUpsideDown:
_rotation = RTCVideoRotation_270;
break;
case UIDeviceOrientationLandscapeLeft:
_rotation = usingFrontCamera ? RTCVideoRotation_180 : RTCVideoRotation_0;
break;
case UIDeviceOrientationLandscapeRight:
_rotation = usingFrontCamera ? RTCVideoRotation_0 : RTCVideoRotation_180;
break;
case UIDeviceOrientationFaceUp:
case UIDeviceOrientationFaceDown:
case UIDeviceOrientationUnknown:
// Ignore.
break;
}
#else
// No rotation on Mac.
_rotation = RTCVideoRotation_0;
#endif
RTC_OBJC_TYPE(RTCCVPixelBuffer) *rtcPixelBuffer =
[[RTC_OBJC_TYPE(RTCCVPixelBuffer) alloc] initWithPixelBuffer:pixelBuffer];
int64_t timeStampNs = CMTimeGetSeconds(CMSampleBufferGetPresentationTimeStamp(sampleBuffer)) *
kNanosecondsPerSecond;
RTC_OBJC_TYPE(RTCVideoFrame) *videoFrame =
[[RTC_OBJC_TYPE(RTCVideoFrame) alloc] initWithBuffer:rtcPixelBuffer
rotation:_rotation
timeStampNs:timeStampNs];
[self.delegate capturer:self didCaptureVideoFrame:videoFrame];
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput
didDropSampleBuffer:(CMSampleBufferRef)sampleBuffer
fromConnection:(AVCaptureConnection *)connection {
#if TARGET_OS_IPHONE
CFStringRef droppedReason =
CMGetAttachment(sampleBuffer, kCMSampleBufferAttachmentKey_DroppedFrameReason, nil);
#else
// DroppedFrameReason unavailable on macOS.
CFStringRef droppedReason = nil;
#endif
RTCLogError(@"Dropped sample buffer. Reason: %@", (__bridge NSString *)droppedReason);
}
#pragma mark - AVCaptureSession notifications
- (void)handleCaptureSessionInterruption:(NSNotification *)notification {
NSString *reasonString = nil;
#if TARGET_OS_IPHONE
NSNumber *reason = notification.userInfo[AVCaptureSessionInterruptionReasonKey];
if (reason) {
switch (reason.intValue) {
case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableInBackground:
reasonString = @"VideoDeviceNotAvailableInBackground";
break;
case AVCaptureSessionInterruptionReasonAudioDeviceInUseByAnotherClient:
reasonString = @"AudioDeviceInUseByAnotherClient";
break;
case AVCaptureSessionInterruptionReasonVideoDeviceInUseByAnotherClient:
reasonString = @"VideoDeviceInUseByAnotherClient";
break;
case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps:
reasonString = @"VideoDeviceNotAvailableWithMultipleForegroundApps";
break;
}
}
#endif
RTCLog(@"Capture session interrupted: %@", reasonString);
}
- (void)handleCaptureSessionInterruptionEnded:(NSNotification *)notification {
RTCLog(@"Capture session interruption ended.");
}
- (void)handleCaptureSessionRuntimeError:(NSNotification *)notification {
NSError *error = [notification.userInfo objectForKey:AVCaptureSessionErrorKey];
RTCLogError(@"Capture session runtime error: %@", error);
[RTC_OBJC_TYPE(RTCDispatcher) dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
#if TARGET_OS_IPHONE
if (error.code == AVErrorMediaServicesWereReset) {
[self handleNonFatalError];
} else {
[self handleFatalError];
}
#else
[self handleFatalError];
#endif
}];
}
- (void)handleCaptureSessionDidStartRunning:(NSNotification *)notification {
RTCLog(@"Capture session started.");
[RTC_OBJC_TYPE(RTCDispatcher) dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
// If we successfully restarted after an unknown
// error, allow future retries on fatal errors.
self.hasRetriedOnFatalError = NO;
}];
}
- (void)handleCaptureSessionDidStopRunning:(NSNotification *)notification {
RTCLog(@"Capture session stopped.");
}
- (void)handleFatalError {
[RTC_OBJC_TYPE(RTCDispatcher)
dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
if (!self.hasRetriedOnFatalError) {
RTCLogWarning(@"Attempting to recover from fatal capture error.");
[self handleNonFatalError];
self.hasRetriedOnFatalError = YES;
} else {
RTCLogError(@"Previous fatal error recovery failed.");
}
}];
}
- (void)handleNonFatalError {
[RTC_OBJC_TYPE(RTCDispatcher) dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
RTCLog(@"Restarting capture session after error.");
if (self.isRunning) {
[self.captureSession startRunning];
}
}];
}
#if TARGET_OS_IPHONE
#pragma mark - UIApplication notifications
- (void)handleApplicationDidBecomeActive:(NSNotification *)notification {
[RTC_OBJC_TYPE(RTCDispatcher)
dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
block:^{
if (self.isRunning && !self.captureSession.isRunning) {
RTCLog(@"Restarting capture session on active.");
[self.captureSession startRunning];
}
}];
}
#endif // TARGET_OS_IPHONE
#pragma mark - Private
- (dispatch_queue_t)frameQueue {
if (!_frameQueue) {
_frameQueue = RTCDispatchQueueCreateWithTarget(
"org.webrtc.cameravideocapturer.video",
DISPATCH_QUEUE_SERIAL,
dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0));
}
return _frameQueue;
}
- (BOOL)setupCaptureSession:(AVCaptureSession *)captureSession {
NSAssert(_captureSession == nil, @"Setup capture session called twice.");
_captureSession = captureSession;
#if defined(WEBRTC_IOS)
_captureSession.sessionPreset = AVCaptureSessionPresetInputPriority;
_captureSession.usesApplicationAudioSession = NO;
#endif
[self setupVideoDataOutput];
// Add the output.
if (![_captureSession canAddOutput:_videoDataOutput]) {
RTCLogError(@"Video data output unsupported.");
return NO;
}
[_captureSession addOutput:_videoDataOutput];
return YES;
}
- (void)setupVideoDataOutput {
NSAssert(_videoDataOutput == nil, @"Setup video data output called twice.");
AVCaptureVideoDataOutput *videoDataOutput = [[AVCaptureVideoDataOutput alloc] init];
// `videoDataOutput.availableVideoCVPixelFormatTypes` returns the pixel formats supported by the
// device with the most efficient output format first. Find the first format that we support.
NSSet<NSNumber *> *supportedPixelFormats =
[RTC_OBJC_TYPE(RTCCVPixelBuffer) supportedPixelFormats];
NSMutableOrderedSet *availablePixelFormats =
[NSMutableOrderedSet orderedSetWithArray:videoDataOutput.availableVideoCVPixelFormatTypes];
[availablePixelFormats intersectSet:supportedPixelFormats];
NSNumber *pixelFormat = availablePixelFormats.firstObject;
NSAssert(pixelFormat, @"Output device has no supported formats.");
_preferredOutputPixelFormat = [pixelFormat unsignedIntValue];
_outputPixelFormat = _preferredOutputPixelFormat;
videoDataOutput.videoSettings = @{(NSString *)kCVPixelBufferPixelFormatTypeKey : pixelFormat};
videoDataOutput.alwaysDiscardsLateVideoFrames = NO;
[videoDataOutput setSampleBufferDelegate:self queue:self.frameQueue];
_videoDataOutput = videoDataOutput;
}
- (void)updateVideoDataOutputPixelFormat:(AVCaptureDeviceFormat *)format {
FourCharCode mediaSubType = CMFormatDescriptionGetMediaSubType(format.formatDescription);
if (![[RTC_OBJC_TYPE(RTCCVPixelBuffer) supportedPixelFormats] containsObject:@(mediaSubType)]) {
mediaSubType = _preferredOutputPixelFormat;
}
if (mediaSubType != _outputPixelFormat) {
_outputPixelFormat = mediaSubType;
}
// Update videoSettings with dimensions, as some virtual cameras, e.g. Snap Camera, may not work
// otherwise.
CMVideoDimensions dimensions = CMVideoFormatDescriptionGetDimensions(format.formatDescription);
_videoDataOutput.videoSettings = @{
(id)kCVPixelBufferWidthKey : @(dimensions.width),
(id)kCVPixelBufferHeightKey : @(dimensions.height),
(id)kCVPixelBufferPixelFormatTypeKey : @(_outputPixelFormat),
};
}
#pragma mark - Private, called inside capture queue
- (void)updateDeviceCaptureFormat:(AVCaptureDeviceFormat *)format fps:(NSInteger)fps {
NSAssert([RTC_OBJC_TYPE(RTCDispatcher) isOnQueueForType:RTCDispatcherTypeCaptureSession],
@"updateDeviceCaptureFormat must be called on the capture queue.");
@try {
_currentDevice.activeFormat = format;
_currentDevice.activeVideoMinFrameDuration = CMTimeMake(1, fps);
} @catch (NSException *exception) {
RTCLogError(@"Failed to set active format!\n User info:%@", exception.userInfo);
return;
}
}
- (void)reconfigureCaptureSessionInput {
NSAssert([RTC_OBJC_TYPE(RTCDispatcher) isOnQueueForType:RTCDispatcherTypeCaptureSession],
@"reconfigureCaptureSessionInput must be called on the capture queue.");
NSError *error = nil;
AVCaptureDeviceInput *input =
[AVCaptureDeviceInput deviceInputWithDevice:_currentDevice error:&error];
if (!input) {
RTCLogError(@"Failed to create front camera input: %@", error.localizedDescription);
return;
}
[_captureSession beginConfiguration];
for (AVCaptureDeviceInput *oldInput in [_captureSession.inputs copy]) {
[_captureSession removeInput:oldInput];
}
if ([_captureSession canAddInput:input]) {
[_captureSession addInput:input];
} else {
RTCLogError(@"Cannot add camera as an input to the session.");
}
[_captureSession commitConfiguration];
}
- (void)updateOrientation {
NSAssert([RTC_OBJC_TYPE(RTCDispatcher) isOnQueueForType:RTCDispatcherTypeCaptureSession],
@"updateOrientation must be called on the capture queue.");
#if TARGET_OS_IPHONE
_orientation = [UIDevice currentDevice].orientation;
#endif
}
@end
|