aboutsummaryrefslogtreecommitdiffstats
path: root/libavdevice/avfoundation.m
blob: 43b2edb44d9e869feec1bf9ffeb2abbfdb3b8ac1 (plain) (blame)
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
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
/*
 * AVFoundation input device
 * Copyright (c) 2014 Thilo Borgmann <thilo.borgmann@mail.de>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * AVFoundation input device
 * @author Thilo Borgmann <thilo.borgmann@mail.de>
 */

#import <AVFoundation/AVFoundation.h>
#include <pthread.h>

#include "libavutil/pixdesc.h"
#include "libavutil/opt.h"
#include "libavutil/avstring.h"
#include "libavformat/internal.h"
#include "libavutil/internal.h"
#include "libavutil/parseutils.h"
#include "libavutil/time.h"
#include "libavutil/imgutils.h"
#include "avdevice.h"

static const int avf_time_base = 1000000;

static const AVRational avf_time_base_q = {
    .num = 1,
    .den = avf_time_base
};

struct AVFPixelFormatSpec {
    enum AVPixelFormat ff_id;
    OSType avf_id;
};

static const struct AVFPixelFormatSpec avf_pixel_formats[] = {
    { AV_PIX_FMT_MONOBLACK,    kCVPixelFormatType_1Monochrome },
    { AV_PIX_FMT_RGB555BE,     kCVPixelFormatType_16BE555 },
    { AV_PIX_FMT_RGB555LE,     kCVPixelFormatType_16LE555 },
    { AV_PIX_FMT_RGB565BE,     kCVPixelFormatType_16BE565 },
    { AV_PIX_FMT_RGB565LE,     kCVPixelFormatType_16LE565 },
    { AV_PIX_FMT_RGB24,        kCVPixelFormatType_24RGB },
    { AV_PIX_FMT_BGR24,        kCVPixelFormatType_24BGR },
    { AV_PIX_FMT_0RGB,         kCVPixelFormatType_32ARGB },
    { AV_PIX_FMT_BGR0,         kCVPixelFormatType_32BGRA },
    { AV_PIX_FMT_0BGR,         kCVPixelFormatType_32ABGR },
    { AV_PIX_FMT_RGB0,         kCVPixelFormatType_32RGBA },
    { AV_PIX_FMT_BGR48BE,      kCVPixelFormatType_48RGB },
    { AV_PIX_FMT_UYVY422,      kCVPixelFormatType_422YpCbCr8 },
    { AV_PIX_FMT_YUVA444P,     kCVPixelFormatType_4444YpCbCrA8R },
    { AV_PIX_FMT_YUVA444P16LE, kCVPixelFormatType_4444AYpCbCr16 },
    { AV_PIX_FMT_YUV444P,      kCVPixelFormatType_444YpCbCr8 },
    { AV_PIX_FMT_YUV422P16,    kCVPixelFormatType_422YpCbCr16 },
    { AV_PIX_FMT_YUV422P10,    kCVPixelFormatType_422YpCbCr10 },
    { AV_PIX_FMT_YUV444P10,    kCVPixelFormatType_444YpCbCr10 },
    { AV_PIX_FMT_YUV420P,      kCVPixelFormatType_420YpCbCr8Planar },
    { AV_PIX_FMT_NV12,         kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange },
    { AV_PIX_FMT_YUYV422,      kCVPixelFormatType_422YpCbCr8_yuvs },
#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1080
    { AV_PIX_FMT_GRAY8,        kCVPixelFormatType_OneComponent8 },
#endif
    { AV_PIX_FMT_NONE, 0 }
};

typedef struct
{
    AVClass*        class;

    int             frames_captured;
    int             audio_frames_captured;
    int64_t         first_pts;
    int64_t         first_audio_pts;
    pthread_mutex_t frame_lock;
    id              avf_delegate;
    id              avf_audio_delegate;

    AVRational      framerate;
    int             width, height;

    int             capture_cursor;
    int             capture_mouse_clicks;
    int             capture_raw_data;
    int             drop_late_frames;
    int             video_is_muxed;

    int             list_devices;
    int             video_device_index;
    int             video_stream_index;
    int             audio_device_index;
    int             audio_stream_index;

    char            *video_filename;
    char            *audio_filename;

    int             num_video_devices;

    int             audio_channels;
    int             audio_bits_per_sample;
    int             audio_float;
    int             audio_be;
    int             audio_signed_integer;
    int             audio_packed;
    int             audio_non_interleaved;

    int32_t         *audio_buffer;
    int             audio_buffer_size;

    enum AVPixelFormat pixel_format;

    AVCaptureSession         *capture_session;
    AVCaptureVideoDataOutput *video_output;
    AVCaptureAudioDataOutput *audio_output;
    CMSampleBufferRef         current_frame;
    CMSampleBufferRef         current_audio_frame;

    AVCaptureDevice          *observed_device;
    AVCaptureDeviceTransportControlsPlaybackMode observed_mode;
    int                      observed_quit;
} AVFContext;

static void lock_frames(AVFContext* ctx)
{
    pthread_mutex_lock(&ctx->frame_lock);
}

static void unlock_frames(AVFContext* ctx)
{
    pthread_mutex_unlock(&ctx->frame_lock);
}

/** FrameReciever class - delegate for AVCaptureSession
 */
@interface AVFFrameReceiver : NSObject
{
    AVFContext* _context;
}

- (id)initWithContext:(AVFContext*)context;

- (void)  captureOutput:(AVCaptureOutput *)captureOutput
  didOutputSampleBuffer:(CMSampleBufferRef)videoFrame
         fromConnection:(AVCaptureConnection *)connection;

@end

@implementation AVFFrameReceiver

- (id)initWithContext:(AVFContext*)context
{
    if (self = [super init]) {
        _context = context;

        // start observing if a device is set for it
        if (_context->observed_device) {
            NSString *keyPath = NSStringFromSelector(@selector(transportControlsPlaybackMode));
            NSKeyValueObservingOptions options = NSKeyValueObservingOptionNew;

            [_context->observed_device addObserver: self
                                        forKeyPath: keyPath
                                           options: options
                                           context: _context];
        }
    }
    return self;
}

- (void)dealloc {
    // stop observing if a device is set for it
    NSString *keyPath = NSStringFromSelector(@selector(transportControlsPlaybackMode));
    [_context->observed_device removeObserver: self forKeyPath: keyPath];
    [super dealloc];
}

- (void)observeValueForKeyPath:(NSString *)keyPath
                      ofObject:(id)object
                        change:(NSDictionary *)change
                       context:(void *)context {
    if (context == _context) {
        AVCaptureDeviceTransportControlsPlaybackMode mode =
            [change[NSKeyValueChangeNewKey] integerValue];

        if (mode != _context->observed_mode) {
            if (mode == AVCaptureDeviceTransportControlsNotPlayingMode) {
                _context->observed_quit = 1;
            }
            _context->observed_mode = mode;
        }
    } else {
        [super observeValueForKeyPath: keyPath
                             ofObject: object
                               change: change
                              context: context];
    }
}

- (void)  captureOutput:(AVCaptureOutput *)captureOutput
  didOutputSampleBuffer:(CMSampleBufferRef)videoFrame
         fromConnection:(AVCaptureConnection *)connection
{
    lock_frames(_context);

    if (_context->current_frame != nil) {
        CFRelease(_context->current_frame);
    }

    _context->current_frame = (CMSampleBufferRef)CFRetain(videoFrame);

    unlock_frames(_context);

    ++_context->frames_captured;
}

@end

/** AudioReciever class - delegate for AVCaptureSession
 */
@interface AVFAudioReceiver : NSObject
{
    AVFContext* _context;
}

- (id)initWithContext:(AVFContext*)context;

- (void)  captureOutput:(AVCaptureOutput *)captureOutput
  didOutputSampleBuffer:(CMSampleBufferRef)audioFrame
         fromConnection:(AVCaptureConnection *)connection;

@end

@implementation AVFAudioReceiver

- (id)initWithContext:(AVFContext*)context
{
    if (self = [super init]) {
        _context = context;
    }
    return self;
}

- (void)  captureOutput:(AVCaptureOutput *)captureOutput
  didOutputSampleBuffer:(CMSampleBufferRef)audioFrame
         fromConnection:(AVCaptureConnection *)connection
{
    lock_frames(_context);

    if (_context->current_audio_frame != nil) {
        CFRelease(_context->current_audio_frame);
    }

    _context->current_audio_frame = (CMSampleBufferRef)CFRetain(audioFrame);

    unlock_frames(_context);

    ++_context->audio_frames_captured;
}

@end

static void destroy_context(AVFContext* ctx)
{
    [ctx->capture_session stopRunning];

    [ctx->capture_session release];
    [ctx->video_output    release];
    [ctx->audio_output    release];
    [ctx->avf_delegate    release];
    [ctx->avf_audio_delegate release];

    ctx->capture_session = NULL;
    ctx->video_output    = NULL;
    ctx->audio_output    = NULL;
    ctx->avf_delegate    = NULL;
    ctx->avf_audio_delegate = NULL;

    av_freep(&ctx->audio_buffer);

    pthread_mutex_destroy(&ctx->frame_lock);

    if (ctx->current_frame) {
        CFRelease(ctx->current_frame);
    }
}

static void parse_device_name(AVFormatContext *s)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;
    char *tmp = av_strdup(s->url);
    char *save;

    if (tmp[0] != ':') {
        ctx->video_filename = av_strtok(tmp,  ":", &save);
        ctx->audio_filename = av_strtok(NULL, ":", &save);
    } else {
        ctx->audio_filename = av_strtok(tmp,  ":", &save);
    }
}

/**
 * Configure the video device.
 *
 * Configure the video device using a run-time approach to access properties
 * since formats, activeFormat are available since  iOS >= 7.0 or OSX >= 10.7
 * and activeVideoMaxFrameDuration is available since i0S >= 7.0 and OSX >= 10.9.
 *
 * The NSUndefinedKeyException must be handled by the caller of this function.
 *
 */
static int configure_video_device(AVFormatContext *s, AVCaptureDevice *video_device)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;

    double framerate = av_q2d(ctx->framerate);
    NSObject *range = nil;
    NSObject *format = nil;
    NSObject *selected_range = nil;
    NSObject *selected_format = nil;

    // try to configure format by formats list
    // might raise an exception if no format list is given
    // (then fallback to default, no configuration)
    @try {
        for (format in [video_device valueForKey:@"formats"]) {
            CMFormatDescriptionRef formatDescription;
            CMVideoDimensions dimensions;

            formatDescription = (CMFormatDescriptionRef) [format performSelector:@selector(formatDescription)];
            dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);

            if ((ctx->width == 0 && ctx->height == 0) ||
                (dimensions.width == ctx->width && dimensions.height == ctx->height)) {

                selected_format = format;

                for (range in [format valueForKey:@"videoSupportedFrameRateRanges"]) {
                    double max_framerate;

                    [[range valueForKey:@"maxFrameRate"] getValue:&max_framerate];
                    if (fabs (framerate - max_framerate) < 0.01) {
                        selected_range = range;
                        break;
                    }
                }
            }
        }

        if (!selected_format) {
            av_log(s, AV_LOG_ERROR, "Selected video size (%dx%d) is not supported by the device.\n",
                ctx->width, ctx->height);
            goto unsupported_format;
        }

        if (!selected_range) {
            av_log(s, AV_LOG_ERROR, "Selected framerate (%f) is not supported by the device.\n",
                framerate);
            if (ctx->video_is_muxed) {
                av_log(s, AV_LOG_ERROR, "Falling back to default.\n");
            } else {
                goto unsupported_format;
            }
        }

        if ([video_device lockForConfiguration:NULL] == YES) {
            if (selected_format) {
                [video_device setValue:selected_format forKey:@"activeFormat"];
            }
            if (selected_range) {
                NSValue *min_frame_duration = [selected_range valueForKey:@"minFrameDuration"];
                [video_device setValue:min_frame_duration forKey:@"activeVideoMinFrameDuration"];
                [video_device setValue:min_frame_duration forKey:@"activeVideoMaxFrameDuration"];
            }
        } else {
            av_log(s, AV_LOG_ERROR, "Could not lock device for configuration.\n");
            return AVERROR(EINVAL);
        }
    } @catch(NSException *e) {
        av_log(ctx, AV_LOG_WARNING, "Configuration of video device failed, falling back to default.\n");
    }

    return 0;

unsupported_format:

    av_log(s, AV_LOG_ERROR, "Supported modes:\n");
    for (format in [video_device valueForKey:@"formats"]) {
        CMFormatDescriptionRef formatDescription;
        CMVideoDimensions dimensions;

        formatDescription = (CMFormatDescriptionRef) [format performSelector:@selector(formatDescription)];
        dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);

        for (range in [format valueForKey:@"videoSupportedFrameRateRanges"]) {
            double min_framerate;
            double max_framerate;

            [[range valueForKey:@"minFrameRate"] getValue:&min_framerate];
            [[range valueForKey:@"maxFrameRate"] getValue:&max_framerate];
            av_log(s, AV_LOG_ERROR, "  %dx%d@[%f %f]fps\n",
                dimensions.width, dimensions.height,
                min_framerate, max_framerate);
        }
    }
    return AVERROR(EINVAL);
}

static int add_video_device(AVFormatContext *s, AVCaptureDevice *video_device)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;
    int ret;
    NSError *error  = nil;
    AVCaptureInput* capture_input = nil;
    struct AVFPixelFormatSpec pxl_fmt_spec;
    NSNumber *pixel_format;
    NSDictionary *capture_dict;
    dispatch_queue_t queue;

    if (ctx->video_device_index < ctx->num_video_devices) {
        capture_input = (AVCaptureInput*) [[[AVCaptureDeviceInput alloc] initWithDevice:video_device error:&error] autorelease];
    } else {
        capture_input = (AVCaptureInput*) video_device;
    }

    if (!capture_input) {
        av_log(s, AV_LOG_ERROR, "Failed to create AV capture input device: %s\n",
               [[error localizedDescription] UTF8String]);
        return 1;
    }

    if ([ctx->capture_session canAddInput:capture_input]) {
        [ctx->capture_session addInput:capture_input];
    } else {
        av_log(s, AV_LOG_ERROR, "can't add video input to capture session\n");
        return 1;
    }

    // Attaching output
    ctx->video_output = [[AVCaptureVideoDataOutput alloc] init];

    if (!ctx->video_output) {
        av_log(s, AV_LOG_ERROR, "Failed to init AV video output\n");
        return 1;
    }

    // Configure device framerate and video size
    @try {
        if ((ret = configure_video_device(s, video_device)) < 0) {
            return ret;
        }
    } @catch (NSException *exception) {
        if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
          av_log (s, AV_LOG_ERROR, "An error occurred: %s", [exception.reason UTF8String]);
          return AVERROR_EXTERNAL;
        }
    }

    // select pixel format
    pxl_fmt_spec.ff_id = AV_PIX_FMT_NONE;

    for (int i = 0; avf_pixel_formats[i].ff_id != AV_PIX_FMT_NONE; i++) {
        if (ctx->pixel_format == avf_pixel_formats[i].ff_id) {
            pxl_fmt_spec = avf_pixel_formats[i];
            break;
        }
    }

    // check if selected pixel format is supported by AVFoundation
    if (pxl_fmt_spec.ff_id == AV_PIX_FMT_NONE) {
        av_log(s, AV_LOG_ERROR, "Selected pixel format (%s) is not supported by AVFoundation.\n",
               av_get_pix_fmt_name(pxl_fmt_spec.ff_id));
        return 1;
    }

    // check if the pixel format is available for this device
    if ([[ctx->video_output availableVideoCVPixelFormatTypes] indexOfObject:[NSNumber numberWithInt:pxl_fmt_spec.avf_id]] == NSNotFound) {
        av_log(s, AV_LOG_ERROR, "Selected pixel format (%s) is not supported by the input device.\n",
               av_get_pix_fmt_name(pxl_fmt_spec.ff_id));

        pxl_fmt_spec.ff_id = AV_PIX_FMT_NONE;

        av_log(s, AV_LOG_ERROR, "Supported pixel formats:\n");
        for (NSNumber *pxl_fmt in [ctx->video_output availableVideoCVPixelFormatTypes]) {
            struct AVFPixelFormatSpec pxl_fmt_dummy;
            pxl_fmt_dummy.ff_id = AV_PIX_FMT_NONE;
            for (int i = 0; avf_pixel_formats[i].ff_id != AV_PIX_FMT_NONE; i++) {
                if ([pxl_fmt intValue] == avf_pixel_formats[i].avf_id) {
                    pxl_fmt_dummy = avf_pixel_formats[i];
                    break;
                }
            }

            if (pxl_fmt_dummy.ff_id != AV_PIX_FMT_NONE) {
                av_log(s, AV_LOG_ERROR, "  %s\n", av_get_pix_fmt_name(pxl_fmt_dummy.ff_id));

                // select first supported pixel format instead of user selected (or default) pixel format
                if (pxl_fmt_spec.ff_id == AV_PIX_FMT_NONE) {
                    pxl_fmt_spec = pxl_fmt_dummy;
                }
            }
        }

        // fail if there is no appropriate pixel format or print a warning about overriding the pixel format
        if (pxl_fmt_spec.ff_id == AV_PIX_FMT_NONE) {
            return 1;
        } else {
            av_log(s, AV_LOG_WARNING, "Overriding selected pixel format to use %s instead.\n",
                   av_get_pix_fmt_name(pxl_fmt_spec.ff_id));
        }
    }

    // set videoSettings to an empty dict for receiving raw data of muxed devices
    if (ctx->capture_raw_data) {
        ctx->pixel_format = pxl_fmt_spec.ff_id;
        ctx->video_output.videoSettings = @{ };
    } else {
        ctx->pixel_format = pxl_fmt_spec.ff_id;
        pixel_format = [NSNumber numberWithUnsignedInt:pxl_fmt_spec.avf_id];
        capture_dict = [NSDictionary dictionaryWithObject:pixel_format
                                                   forKey:(id)kCVPixelBufferPixelFormatTypeKey];

        [ctx->video_output setVideoSettings:capture_dict];
    }
    [ctx->video_output setAlwaysDiscardsLateVideoFrames:ctx->drop_late_frames];

    // check for transport control support and set observer device if supported
    int trans_ctrl = [video_device transportControlsSupported];
    AVCaptureDeviceTransportControlsPlaybackMode trans_mode = [video_device transportControlsPlaybackMode];

    if (trans_ctrl) {
        ctx->observed_mode   = trans_mode;
        ctx->observed_device = video_device;
    }

    ctx->avf_delegate = [[AVFFrameReceiver alloc] initWithContext:ctx];

    queue = dispatch_queue_create("avf_queue", NULL);
    [ctx->video_output setSampleBufferDelegate:ctx->avf_delegate queue:queue];
    dispatch_release(queue);

    if ([ctx->capture_session canAddOutput:ctx->video_output]) {
        [ctx->capture_session addOutput:ctx->video_output];
    } else {
        av_log(s, AV_LOG_ERROR, "can't add video output to capture session\n");
        return 1;
    }

    return 0;
}

static int add_audio_device(AVFormatContext *s, AVCaptureDevice *audio_device)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;
    NSError *error  = nil;
    AVCaptureDeviceInput* audio_dev_input = [[[AVCaptureDeviceInput alloc] initWithDevice:audio_device error:&error] autorelease];
    dispatch_queue_t queue;

    if (!audio_dev_input) {
        av_log(s, AV_LOG_ERROR, "Failed to create AV capture input device: %s\n",
               [[error localizedDescription] UTF8String]);
        return 1;
    }

    if ([ctx->capture_session canAddInput:audio_dev_input]) {
        [ctx->capture_session addInput:audio_dev_input];
    } else {
        av_log(s, AV_LOG_ERROR, "can't add audio input to capture session\n");
        return 1;
    }

    // Attaching output
    ctx->audio_output = [[AVCaptureAudioDataOutput alloc] init];

    if (!ctx->audio_output) {
        av_log(s, AV_LOG_ERROR, "Failed to init AV audio output\n");
        return 1;
    }

    ctx->avf_audio_delegate = [[AVFAudioReceiver alloc] initWithContext:ctx];

    queue = dispatch_queue_create("avf_audio_queue", NULL);
    [ctx->audio_output setSampleBufferDelegate:ctx->avf_audio_delegate queue:queue];
    dispatch_release(queue);

    if ([ctx->capture_session canAddOutput:ctx->audio_output]) {
        [ctx->capture_session addOutput:ctx->audio_output];
    } else {
        av_log(s, AV_LOG_ERROR, "adding audio output to capture session failed\n");
        return 1;
    }

    return 0;
}

static int get_video_config(AVFormatContext *s)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;
    CVImageBufferRef image_buffer;
    CMBlockBufferRef block_buffer;
    CGSize image_buffer_size;
    AVStream* stream = avformat_new_stream(s, NULL);

    if (!stream) {
        return 1;
    }

    // Take stream info from the first frame.
    while (ctx->frames_captured < 1) {
        CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.1, YES);
    }

    lock_frames(ctx);

    ctx->video_stream_index = stream->index;

    avpriv_set_pts_info(stream, 64, 1, avf_time_base);

    image_buffer = CMSampleBufferGetImageBuffer(ctx->current_frame);
    block_buffer = CMSampleBufferGetDataBuffer(ctx->current_frame);

    if (image_buffer) {
        image_buffer_size = CVImageBufferGetEncodedSize(image_buffer);

        stream->codecpar->codec_id   = AV_CODEC_ID_RAWVIDEO;
        stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
        stream->codecpar->width      = (int)image_buffer_size.width;
        stream->codecpar->height     = (int)image_buffer_size.height;
        stream->codecpar->format     = ctx->pixel_format;
    } else {
        stream->codecpar->codec_id   = AV_CODEC_ID_DVVIDEO;
        stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
        stream->codecpar->format     = ctx->pixel_format;
    }

    CFRelease(ctx->current_frame);
    ctx->current_frame = nil;

    unlock_frames(ctx);

    return 0;
}

static int get_audio_config(AVFormatContext *s)
{
    AVFContext *ctx = (AVFContext*)s->priv_data;
    CMFormatDescriptionRef format_desc;
    AVStream* stream = avformat_new_stream(s, NULL);

    if (!stream) {
        return 1;
    }

    // Take stream info from the first frame.
    while (ctx->audio_frames_captured < 1) {
        CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.1, YES);
    }

    lock_frames(ctx);

    ctx->audio_stream_index = stream->index;

    avpriv_set_pts_info(stream, 64, 1, avf_time_base);

    format_desc = CMSampleBufferGetFormatDescription(ctx->current_audio_frame);
    const AudioStreamBasicDescription *basic_desc = CMAudioFormatDescriptionGetStreamBasicDescription(format_desc);

    if (!basic_desc) {
        av_log(s, AV_LOG_ERROR, "audio format not available\n");
        return 1;
    }

    stream->codecpar->codec_type     = AVMEDIA_TYPE_AUDIO;
    stream->codecpar->sample_rate    = basic_desc->mSampleRate;
    stream->codecpar->channels       = basic_desc->mChannelsPerFrame;
    stream->codecpar->channel_layout = av_get_default_channel_layout(stream->codecpar->channels);

    ctx->audio_channels        = basic_desc->mChannelsPerFrame;
    ctx->audio_bits_per_sample = basic_desc->mBitsPerChannel;
    ctx->audio_float           = basic_desc->mFormatFlags & kAudioFormatFlagIsFloat;
    ctx->audio_be              = basic_desc->mFormatFlags & kAudioFormatFlagIsBigEndian;
    ctx->audio_signed_integer  = basic_desc->mFormatFlags & kAudioFormatFlagIsSignedInteger;
    ctx->audio_packed          = basic_desc->mFormatFlags & kAudioFormatFlagIsPacked;
    ctx->audio_non_interleaved = basic_desc->mFormatFlags & kAudioFormatFlagIsNonInterleaved;

    if (basic_desc->mFormatID == kAudioFormatLinearPCM &&
        ctx->audio_float &&
        ctx->audio_bits_per_sample == 32 &&
        ctx->audio_packed) {
        stream->codecpar->codec_id = ctx->audio_be ? AV_CODEC_ID_PCM_F32BE : AV_CODEC_ID_PCM_F32LE;
    } else if (basic_desc->mFormatID == kAudioFormatLinearPCM &&
        ctx->audio_signed_integer &&
        ctx->audio_bits_per_sample == 16 &&
        ctx->audio_packed) {
        stream->codecpar->codec_id = ctx->audio_be ? AV_CODEC_ID_PCM_S16BE : AV_CODEC_ID_PCM_S16LE;
    } else if (basic_desc->mFormatID == kAudioFormatLinearPCM &&
        ctx->audio_signed_integer &&
        ctx->audio_bits_per_sample == 24 &&
        ctx->audio_packed) {
        stream->codecpar->codec_id = ctx->audio_be ? AV_CODEC_ID_PCM_S24BE : AV_CODEC_ID_PCM_S24LE;
    } else if (basic_desc->mFormatID == kAudioFormatLinearPCM &&
        ctx->audio_signed_integer &&
        ctx->audio_bits_per_sample == 32 &&
        ctx->audio_packed) {
        stream->codecpar->codec_id = ctx->audio_be ? AV_CODEC_ID_PCM_S32BE : AV_CODEC_ID_PCM_S32LE;
    } else {
        av_log(s, AV_LOG_ERROR, "audio format is not supported\n");
        return 1;
    }

    if (ctx->audio_non_interleaved) {
        CMBlockBufferRef block_buffer = CMSampleBufferGetDataBuffer(ctx->current_audio_frame);
        ctx->audio_buffer_size        = CMBlockBufferGetDataLength(block_buffer);
        ctx->audio_buffer             = av_malloc(ctx->audio_buffer_size);
        if (!ctx->audio_buffer) {
            av_log(s, AV_LOG_ERROR, "error allocating audio buffer\n");
            return 1;
        }
    }

    CFRelease(ctx->current_audio_frame);
    ctx->current_audio_frame = nil;

    unlock_frames(ctx);

    return 0;
}

static int avf_read_header(AVFormatContext *s)
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    int capture_screen      = 0;
    uint32_t num_screens    = 0;
    AVFContext *ctx         = (AVFContext*)s->priv_data;
    AVCaptureDevice *video_device = nil;
    AVCaptureDevice *audio_device = nil;
    // Find capture device
    NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    NSArray *devices_muxed = [AVCaptureDevice devicesWithMediaType:AVMediaTypeMuxed];

    ctx->num_video_devices = [devices count] + [devices_muxed count];
    ctx->first_pts          = av_gettime();
    ctx->first_audio_pts    = av_gettime();

    pthread_mutex_init(&ctx->frame_lock, NULL);

#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
    CGGetActiveDisplayList(0, NULL, &num_screens);
#endif

    // List devices if requested
    if (ctx->list_devices) {
        int index = 0;
        av_log(ctx, AV_LOG_INFO, "AVFoundation video devices:\n");
        for (AVCaptureDevice *device in devices) {
            const char *name = [[device localizedName] UTF8String];
            index            = [devices indexOfObject:device];
            av_log(ctx, AV_LOG_INFO, "[%d] %s\n", index, name);
        }
        for (AVCaptureDevice *device in devices_muxed) {
            const char *name = [[device localizedName] UTF8String];
            index            = [devices count] + [devices_muxed indexOfObject:device];
            av_log(ctx, AV_LOG_INFO, "[%d] %s\n", index, name);
        }
#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
        if (num_screens > 0) {
            CGDirectDisplayID screens[num_screens];
            CGGetActiveDisplayList(num_screens, screens, &num_screens);
            for (int i = 0; i < num_screens; i++) {
                av_log(ctx, AV_LOG_INFO, "[%d] Capture screen %d\n", ctx->num_video_devices + i, i);
            }
        }
#endif

        av_log(ctx, AV_LOG_INFO, "AVFoundation audio devices:\n");
        devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio];
        for (AVCaptureDevice *device in devices) {
            const char *name = [[device localizedName] UTF8String];
            int index  = [devices indexOfObject:device];
            av_log(ctx, AV_LOG_INFO, "[%d] %s\n", index, name);
        }
         goto fail;
    }

    // parse input filename for video and audio device
    parse_device_name(s);

    // check for device index given in filename
    if (ctx->video_device_index == -1 && ctx->video_filename) {
        sscanf(ctx->video_filename, "%d", &ctx->video_device_index);
    }
    if (ctx->audio_device_index == -1 && ctx->audio_filename) {
        sscanf(ctx->audio_filename, "%d", &ctx->audio_device_index);
    }

    if (ctx->video_device_index >= 0) {
        if (ctx->video_device_index < ctx->num_video_devices) {
            if (ctx->video_device_index < [devices count]) {
                video_device = [devices objectAtIndex:ctx->video_device_index];
            } else {
                video_device = [devices_muxed objectAtIndex:(ctx->video_device_index - [devices count])];
                ctx->video_is_muxed = 1;
            }
        } else if (ctx->video_device_index < ctx->num_video_devices + num_screens) {
#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
            CGDirectDisplayID screens[num_screens];
            CGGetActiveDisplayList(num_screens, screens, &num_screens);
            AVCaptureScreenInput* capture_screen_input = [[[AVCaptureScreenInput alloc] initWithDisplayID:screens[ctx->video_device_index - ctx->num_video_devices]] autorelease];

            if (ctx->framerate.num > 0) {
                capture_screen_input.minFrameDuration = CMTimeMake(ctx->framerate.den, ctx->framerate.num);
            }

#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1080
            if (ctx->capture_cursor) {
                capture_screen_input.capturesCursor = YES;
            } else {
                capture_screen_input.capturesCursor = NO;
            }
#endif

            if (ctx->capture_mouse_clicks) {
                capture_screen_input.capturesMouseClicks = YES;
            } else {
                capture_screen_input.capturesMouseClicks = NO;
            }

            video_device = (AVCaptureDevice*) capture_screen_input;
            capture_screen = 1;
#endif
         } else {
            av_log(ctx, AV_LOG_ERROR, "Invalid device index\n");
            goto fail;
        }
    } else if (ctx->video_filename &&
               strncmp(ctx->video_filename, "none", 4)) {
        if (!strncmp(ctx->video_filename, "default", 7)) {
            video_device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
        } else {
        // looking for video inputs
        for (AVCaptureDevice *device in devices) {
            if (!strncmp(ctx->video_filename, [[device localizedName] UTF8String], strlen(ctx->video_filename))) {
                video_device = device;
                break;
            }
        }
        // looking for muxed inputs
        for (AVCaptureDevice *device in devices_muxed) {
            if (!strncmp(ctx->video_filename, [[device localizedName] UTF8String], strlen(ctx->video_filename))) {
                video_device = device;
                ctx->video_is_muxed = 1;
                break;
            }
        }

#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
        // looking for screen inputs
        if (!video_device) {
            int idx;
            if(sscanf(ctx->video_filename, "Capture screen %d", &idx) && idx < num_screens) {
                CGDirectDisplayID screens[num_screens];
                CGGetActiveDisplayList(num_screens, screens, &num_screens);
                AVCaptureScreenInput* capture_screen_input = [[[AVCaptureScreenInput alloc] initWithDisplayID:screens[idx]] autorelease];
                video_device = (AVCaptureDevice*) capture_screen_input;
                ctx->video_device_index = ctx->num_video_devices + idx;
                capture_screen = 1;

                if (ctx->framerate.num > 0) {
                    capture_screen_input.minFrameDuration = CMTimeMake(ctx->framerate.den, ctx->framerate.num);
                }

#if !TARGET_OS_IPHONE && __MAC_OS_X_VERSION_MIN_REQUIRED >= 1080
                if (ctx->capture_cursor) {
                    capture_screen_input.capturesCursor = YES;
                } else {
                    capture_screen_input.capturesCursor = NO;
                }
#endif

                if (ctx->capture_mouse_clicks) {
                    capture_screen_input.capturesMouseClicks = YES;
                } else {
                    capture_screen_input.capturesMouseClicks = NO;
                }
            }
        }
#endif
        }

        if (!video_device) {
            av_log(ctx, AV_LOG_ERROR, "Video device not found\n");
            goto fail;
        }
    }

    // get audio device
    if (ctx->audio_device_index >= 0) {
        NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio];

        if (ctx->audio_device_index >= [devices count]) {
            av_log(ctx, AV_LOG_ERROR, "Invalid audio device index\n");
            goto fail;
        }

        audio_device = [devices objectAtIndex:ctx->audio_device_index];
    } else if (ctx->audio_filename &&
               strncmp(ctx->audio_filename, "none", 4)) {
        if (!strncmp(ctx->audio_filename, "default", 7)) {
            audio_device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
        } else {
        NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio];

        for (AVCaptureDevice *device in devices) {
            if (!strncmp(ctx->audio_filename, [[device localizedName] UTF8String], strlen(ctx->audio_filename))) {
                audio_device = device;
                break;
            }
        }
        }

        if (!audio_device) {
            av_log(ctx, AV_LOG_ERROR, "Audio device not found\n");
             goto fail;
        }
    }

    // Video nor Audio capture device not found, looking for AVMediaTypeVideo/Audio
    if (!video_device && !audio_device) {
        av_log(s, AV_LOG_ERROR, "No AV capture device found\n");
        goto fail;
    }

    if (video_device) {
        if (ctx->video_device_index < ctx->num_video_devices) {
            av_log(s, AV_LOG_DEBUG, "'%s' opened\n", [[video_device localizedName] UTF8String]);
        } else {
            av_log(s, AV_LOG_DEBUG, "'%s' opened\n", [[video_device description] UTF8String]);
        }
    }
    if (audio_device) {
        av_log(s, AV_LOG_DEBUG, "audio device '%s' opened\n", [[audio_device localizedName] UTF8String]);
    }

    // Initialize capture session
    ctx->capture_session = [[AVCaptureSession alloc] init];

    if (video_device && add_video_device(s, video_device)) {
        goto fail;
    }
    if (audio_device && add_audio_device(s, audio_device)) {
    }

    [ctx->capture_session startRunning];

    /* Unlock device configuration only after the session is started so it
     * does not reset the capture formats */
    if (!capture_screen) {
        [video_device unlockForConfiguration];
    }

    if (video_device && get_video_config(s)) {
        goto fail;
    }

    // set audio stream
    if (audio_device && get_audio_config(s)) {
        goto fail;
    }

    [pool release];
    return 0;

fail:
    [pool release];
    destroy_context(ctx);
    return AVERROR(EIO);
}

static int copy_cvpixelbuffer(AVFormatContext *s,
                               CVPixelBufferRef image_buffer,
                               AVPacket *pkt)
{
    AVFContext *ctx = s->priv_data;
    int src_linesize[4];
    const uint8_t *src_data[4];
    int width  = CVPixelBufferGetWidth(image_buffer);
    int height = CVPixelBufferGetHeight(image_buffer);
    int status;

    memset(src_linesize, 0, sizeof(src_linesize));
    memset(src_data, 0, sizeof(src_data));

    status = CVPixelBufferLockBaseAddress(image_buffer, 0);
    if (status != kCVReturnSuccess) {
        av_log(s, AV_LOG_ERROR, "Could not lock base address: %d (%dx%d)\n", status, width, height);
        return AVERROR_EXTERNAL;
    }

    if (CVPixelBufferIsPlanar(image_buffer)) {
        size_t plane_count = CVPixelBufferGetPlaneCount(image_buffer);
        int i;
        for(i = 0; i < plane_count; i++){
            src_linesize[i] = CVPixelBufferGetBytesPerRowOfPlane(image_buffer, i);
            src_data[i] = CVPixelBufferGetBaseAddressOfPlane(image_buffer, i);
        }
    } else {
        src_linesize[0] = CVPixelBufferGetBytesPerRow(image_buffer);
        src_data[0] = CVPixelBufferGetBaseAddress(image_buffer);
    }

    status = av_image_copy_to_buffer(pkt->data, pkt->size,
                                     src_data, src_linesize,
                                     ctx->pixel_format, width, height, 1);



    CVPixelBufferUnlockBaseAddress(image_buffer, 0);

    return status;
}

static int avf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    AVFContext* ctx = (AVFContext*)s->priv_data;

    do {
        CVImageBufferRef image_buffer;
        CMBlockBufferRef block_buffer;
        lock_frames(ctx);

        if (ctx->current_frame != nil) {
            int status;
            int length = 0;

            image_buffer = CMSampleBufferGetImageBuffer(ctx->current_frame);
            block_buffer = CMSampleBufferGetDataBuffer(ctx->current_frame);

            if (image_buffer != nil) {
                length = (int)CVPixelBufferGetDataSize(image_buffer);
            } else if (block_buffer != nil) {
                length = (int)CMBlockBufferGetDataLength(block_buffer);
            } else  {
                return AVERROR(EINVAL);
            }

            if (av_new_packet(pkt, length) < 0) {
                return AVERROR(EIO);
            }

            CMItemCount count;
            CMSampleTimingInfo timing_info;

            if (CMSampleBufferGetOutputSampleTimingInfoArray(ctx->current_frame, 1, &timing_info, &count) == noErr) {
                AVRational timebase_q = av_make_q(1, timing_info.presentationTimeStamp.timescale);
                pkt->pts = pkt->dts = av_rescale_q(timing_info.presentationTimeStamp.value, timebase_q, avf_time_base_q);
            }

            pkt->stream_index  = ctx->video_stream_index;
            pkt->flags        |= AV_PKT_FLAG_KEY;

            if (image_buffer) {
                status = copy_cvpixelbuffer(s, image_buffer, pkt);
            } else {
                status = 0;
                OSStatus ret = CMBlockBufferCopyDataBytes(block_buffer, 0, pkt->size, pkt->data);
                if (ret != kCMBlockBufferNoErr) {
                    status = AVERROR(EIO);
                }
             }
            CFRelease(ctx->current_frame);
            ctx->current_frame = nil;

            if (status < 0)
                return status;
        } else if (ctx->current_audio_frame != nil) {
            CMBlockBufferRef block_buffer = CMSampleBufferGetDataBuffer(ctx->current_audio_frame);
            int block_buffer_size         = CMBlockBufferGetDataLength(block_buffer);

            if (!block_buffer || !block_buffer_size) {
                return AVERROR(EIO);
            }

            if (ctx->audio_non_interleaved && block_buffer_size > ctx->audio_buffer_size) {
                return AVERROR_BUFFER_TOO_SMALL;
            }

            if (av_new_packet(pkt, block_buffer_size) < 0) {
                return AVERROR(EIO);
            }

            CMItemCount count;
            CMSampleTimingInfo timing_info;

            if (CMSampleBufferGetOutputSampleTimingInfoArray(ctx->current_audio_frame, 1, &timing_info, &count) == noErr) {
                AVRational timebase_q = av_make_q(1, timing_info.presentationTimeStamp.timescale);
                pkt->pts = pkt->dts = av_rescale_q(timing_info.presentationTimeStamp.value, timebase_q, avf_time_base_q);
            }

            pkt->stream_index  = ctx->audio_stream_index;
            pkt->flags        |= AV_PKT_FLAG_KEY;

            if (ctx->audio_non_interleaved) {
                int sample, c, shift, num_samples;

                OSStatus ret = CMBlockBufferCopyDataBytes(block_buffer, 0, pkt->size, ctx->audio_buffer);
                if (ret != kCMBlockBufferNoErr) {
                    return AVERROR(EIO);
                }

                num_samples = pkt->size / (ctx->audio_channels * (ctx->audio_bits_per_sample >> 3));

                // transform decoded frame into output format
                #define INTERLEAVE_OUTPUT(bps)                                         \
                {                                                                      \
                    int##bps##_t **src;                                                \
                    int##bps##_t *dest;                                                \
                    src = av_malloc(ctx->audio_channels * sizeof(int##bps##_t*));      \
                    if (!src) return AVERROR(EIO);                                     \
                    for (c = 0; c < ctx->audio_channels; c++) {                        \
                        src[c] = ((int##bps##_t*)ctx->audio_buffer) + c * num_samples; \
                    }                                                                  \
                    dest  = (int##bps##_t*)pkt->data;                                  \
                    shift = bps - ctx->audio_bits_per_sample;                          \
                    for (sample = 0; sample < num_samples; sample++)                   \
                        for (c = 0; c < ctx->audio_channels; c++)                      \
                            *dest++ = src[c][sample] << shift;                         \
                    av_freep(&src);                                                    \
                }

                if (ctx->audio_bits_per_sample <= 16) {
                    INTERLEAVE_OUTPUT(16)
                } else {
                    INTERLEAVE_OUTPUT(32)
                }
            } else {
                OSStatus ret = CMBlockBufferCopyDataBytes(block_buffer, 0, pkt->size, pkt->data);
                if (ret != kCMBlockBufferNoErr) {
                    return AVERROR(EIO);
                }
            }

            CFRelease(ctx->current_audio_frame);
            ctx->current_audio_frame = nil;
        } else {
            pkt->data = NULL;
            unlock_frames(ctx);
            if (ctx->observed_quit) {
                return AVERROR_EOF;
            } else {
                return AVERROR(EAGAIN);
            }
        }

        unlock_frames(ctx);
    } while (!pkt->data);

    return 0;
}

static int avf_close(AVFormatContext *s)
{
    AVFContext* ctx = (AVFContext*)s->priv_data;
    destroy_context(ctx);
    return 0;
}

static const AVOption options[] = {
    { "list_devices", "list available devices", offsetof(AVFContext, list_devices), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
    { "video_device_index", "select video device by index for devices with same name (starts at 0)", offsetof(AVFContext, video_device_index), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
    { "audio_device_index", "select audio device by index for devices with same name (starts at 0)", offsetof(AVFContext, audio_device_index), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
    { "pixel_format", "set pixel format", offsetof(AVFContext, pixel_format), AV_OPT_TYPE_PIXEL_FMT, {.i64 = AV_PIX_FMT_YUV420P}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM},
    { "framerate", "set frame rate", offsetof(AVFContext, framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "ntsc"}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
    { "video_size", "set video size", offsetof(AVFContext, width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
    { "capture_cursor", "capture the screen cursor", offsetof(AVFContext, capture_cursor), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
    { "capture_mouse_clicks", "capture the screen mouse clicks", offsetof(AVFContext, capture_mouse_clicks), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
    { "capture_raw_data", "capture the raw data from device connection", offsetof(AVFContext, capture_raw_data), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
    { "drop_late_frames", "drop frames that are available later than expected", offsetof(AVFContext, drop_late_frames), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },

    { NULL },
};

static const AVClass avf_class = {
    .class_name = "AVFoundation indev",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
    .category   = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT,
};

AVInputFormat ff_avfoundation_demuxer = {
    .name           = "avfoundation",
    .long_name      = NULL_IF_CONFIG_SMALL("AVFoundation input device"),
    .priv_data_size = sizeof(AVFContext),
    .read_header    = avf_read_header,
    .read_packet    = avf_read_packet,
    .read_close     = avf_close,
    .flags          = AVFMT_NOFILE,
    .priv_class     = &avf_class,
};