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• ffmpeg_videotoolbox : skip memory copy if hwaccel_output_format match

  27 avril 2021, par zhilizhao

  ffmpeg_videotoolbox : skip memory copy if hwaccel_output_format match
  Simple test results :
  Command :
  
  ./ffmpeg -y -hwaccel videotoolbox -hwaccel_output_format videotoolbox_vld \
  
    -i test.mp4 -an -c:v h264_videotoolbox -benchmark out.mp4
  Before :
  
  frame= 1221 fps= 66 q=-0.0 Lsize=    3144kB time=00:00:20.33 bitrate=1266.6kbits/s dup=4 drop=0 speed= 1.1x
  
  bench : utime=2.714s stime=1.218s rtime=18.574s
  After :
  
  frame= 1221 fps=137 q=-0.0 Lsize=    3144kB time=00:00:20.33 bitrate=1266.4kbits/s dup=4 drop=0 speed=2.28x
  
  bench : utime=1.450s stime=1.440s rtime=8.924s
  It has limited usecase since there is no video filter support, so
  
  a log message is added to notify the user.
  Reviewed-by : Steven Liu <liuqi05@kuaishou.com>
  

  • [DH] fftools/ffmpeg_videotoolbox.c

• iOS GPUImage : which AVAssetWriter settings to match 'Constrained Baseline' h.264

  15 août 2014, par sunilr

  I have an iOS app which records video using GPUImage. These videos are stored remotely for viewing by other devices. I’d like the resulting video compression to match the settings which are commonly used in Instagram’s videos. I’ve inspected a number of instagram videos and running ffmpeg -i on them results in :

  Stream #0:0(und) : Video : h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 640x640 [SAR 1:1 DAR 1:1], 1104 kb/s, 29.97 fps, 29.97 tbr, 11988 tbn, 59.94 tbc (default)

  How should i match these ? The current settings i’m using are very close to the GPUImage defaults :

  NSDictionary *videoCleanApertureSettings = [NSDictionary dictionaryWithObjectsAndKeys:
  
                                              [NSNumber numberWithInt:videoSize.width], AVVideoCleanApertureWidthKey,
  
                                              [NSNumber numberWithInt:videoSize.height], AVVideoCleanApertureHeightKey,
  
                                              [NSNumber numberWithInt:0], AVVideoCleanApertureHorizontalOffsetKey,
  
                                              [NSNumber numberWithInt:0], AVVideoCleanApertureVerticalOffsetKey,
  
                                              nil];
  
  
  
  NSDictionary *videoAspectRatioSettings = [NSDictionary dictionaryWithObjectsAndKeys:
  
                                            [NSNumber numberWithInt:1], AVVideoPixelAspectRatioHorizontalSpacingKey,
  
                                            [NSNumber numberWithInt:1], AVVideoPixelAspectRatioVerticalSpacingKey,
  
                                            nil];
  
  
  
  NSMutableDictionary * compressionProperties = [[NSMutableDictionary alloc] init];
  
  [compressionProperties setObject:videoCleanApertureSettings forKey:AVVideoCleanApertureKey];
  
  [compressionProperties setObject:videoAspectRatioSettings forKey:AVVideoPixelAspectRatioKey];
  
  [compressionProperties setObject:[NSNumber numberWithInt: 1100000] forKey:AVVideoAverageBitRateKey];
  
  [compressionProperties setObject:[NSNumber numberWithInt: 16] forKey:AVVideoMaxKeyFrameIntervalKey];
  
  [compressionProperties setObject:AVVideoProfileLevelH264BaselineAutoLevel forKey:AVVideoProfileLevelKey];
  
  
  
  NSMutableDictionary *settings = [[NSMutableDictionary alloc] init];
  
  [settings setObject:AVVideoCodecH264 forKey:AVVideoCodecKey];
  
  [settings setObject:[NSNumber numberWithInt:videoSize.width] forKey:AVVideoWidthKey];
  
  [settings setObject:[NSNumber numberWithInt:videoSize.height] forKey:AVVideoHeightKey];
  
  [settings setObject:compressionProperties forKey:AVVideoCompressionPropertiesKey];

  But when i run ffmpeg -i on the videos created, i get :

  Stream #0:0(und) : Video : h264 (Baseline) (avc1 / 0x31637661), yuv420p, 480x480, 1128 kb/s, SAR 1:1 DAR 1:1, 23.86 fps, 24 tbr, 600 tbn, 1200 tbc (default)

  I’m not sure what the difference is between ’Baseline’ and ’Constrained Baseline’ is, so it may be that the settings i have are adequate (for playback of the video from a remote URL on a mobile device).

  Running an ffmpeg conversion on the file with : ffmpeg -i -profile:v baseline DOES recreate the instagram settings, but i’d like to have this happen on the device if possible.

• ituh263dec : Have function signature match across declaration and definition

  31 octobre 2016, par Diego Biurrun

  ituh263dec : Have function signature match across declaration and definition
  libavcodec/ituh263dec.c(215) : warning C4028 : formal parameter 1 different from declaration
  
  libavcodec/ituh263dec.c(215) : warning C4028 : formal parameter 2 different from declaration
  

  • [DBH] libavcodec/h263.h