Hello, I posted a similar issue recently where an unknown SAR was declared as 1:1 when stream copied to matroska.
I think this is a different issue because the SAR is declared in the source in this instance. I am running some tests on the xiph/derf collection and found that a lot of the videos had different aspect ratios when stream copied to matroska. I am wondering if this is an issue with the Matroska specifcation or some issue with ffmpeg. For what it's worth, I looked at the output file in mediaconch and PixelWidth is listed as 176, and DisplayWidth is listed as 193. Source can be downloaded from here https://media.xiph.org/video/derf/y4m/bus_qcif_15fps.y4m Full command and output at the bottom of the email, but here's the key details from the input: Input #0, yuv4mpegpipe, from 'bus_qcif_15fps.y4m': Duration: 00:00:05.00, start: 0.000000, bitrate: 4562 kb/s Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 176x144, SAR 128:117 DAR 1408:1053, 15 fps, 15 tbr, 15 tbn, 15 tbc and the output: Input #0, matroska,webm, from 'out.mkv': Metadata: ENCODER : Lavf57.41.100 Duration: 00:00:05.00, start: 0.000000, bitrate: 4568 kb/s Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 176x144, SAR 193:176 DAR 193:144, 15 fps, 15 tbr, 1k tbn, 1k tbc (default) 2 outputs will follow: 1. Stream copy to Matroska 2. ffmpeg -i of output file 1. ffmpeg -i bus_qcif_15fps.y4m -c copy out.mkv ffmpeg version N-44317-g7af44ce Copyright (c) 2000-2016 the FFmpeg developers built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3) configuration: --prefix=/home/kieranjol/.linuxbrew/Cellar/ffmpeg/HEAD --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=/usr/bin/gcc-4.8 --host-cflags='-Os -w -pipe -march=core2' --host-ldflags='-L/home/kieranjol/.linuxbrew/lib -Wl,--dynamic-linker=/home/kieranjol/.linuxbrew/lib/ld.so -Wl,-rpath,/home/kieranjol/.linuxbrew/lib' --enable-libx264 --enable-libmp3lame --enable-libxvid --enable-vda libavutil 55. 28.100 / 55. 28.100 libavcodec 57. 50.100 / 57. 50.100 libavformat 57. 41.100 / 57. 41.100 libavdevice 57. 0.102 / 57. 0.102 libavfilter 6. 47.100 / 6. 47.100 libavresample 3. 0. 0 / 3. 0. 0 libswscale 4. 1.100 / 4. 1.100 libswresample 2. 1.100 / 2. 1.100 libpostproc 54. 0.100 / 54. 0.100 Input #0, yuv4mpegpipe, from 'bus_qcif_15fps.y4m': Duration: 00:00:05.00, start: 0.000000, bitrate: 4562 kb/s Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 176x144, SAR 128:117 DAR 1408:1053, 15 fps, 15 tbr, 15 tbn, 15 tbc File 'out.mkv' already exists. Overwrite ? [y/N] y [matroska @ 0x21ba860] Using AVStream.codec to pass codec parameters to muxers is deprecated, use AVStream.codecpar instead. Output #0, matroska, to 'out.mkv': Metadata: encoder : Lavf57.41.100 Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 176x144 [SAR 128:117 DAR 1408:1053], q=2-31, 15 fps, 15 tbr, 1k tbn, 15 tbc Stream mapping: Stream #0:0 -> #0:0 (copy) Press [q] to stop, [?] for help frame= 75 fps=0.0 q=-1.0 Lsize= 2788kB time=00:00:04.93 bitrate=4629.1kbits/s speed= 115x video:2784kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.134154% 2. ffmpeg -i out.mkv ffmpeg version N-44317-g7af44ce Copyright (c) 2000-2016 the FFmpeg developers built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3) configuration: --prefix=/home/kieranjol/.linuxbrew/Cellar/ffmpeg/HEAD --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=/usr/bin/gcc-4.8 --host-cflags='-Os -w -pipe -march=core2' --host-ldflags='-L/home/kieranjol/.linuxbrew/lib -Wl,--dynamic-linker=/home/kieranjol/.linuxbrew/lib/ld.so -Wl,-rpath,/home/kieranjol/.linuxbrew/lib' --enable-libx264 --enable-libmp3lame --enable-libxvid --enable-vda libavutil 55. 28.100 / 55. 28.100 libavcodec 57. 50.100 / 57. 50.100 libavformat 57. 41.100 / 57. 41.100 libavdevice 57. 0.102 / 57. 0.102 libavfilter 6. 47.100 / 6. 47.100 libavresample 3. 0. 0 / 3. 0. 0 libswscale 4. 1.100 / 4. 1.100 libswresample 2. 1.100 / 2. 1.100 libpostproc 54. 0.100 / 54. 0.100 Input #0, matroska,webm, from 'out.mkv': Metadata: ENCODER : Lavf57.41.100 Duration: 00:00:05.00, start: 0.000000, bitrate: 4568 kb/s Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 176x144, SAR 193:176 DAR 193:144, 15 fps, 15 tbr, 1k tbn, 1k tbc (default) Metadata: DURATION : 00:00:05.000000000 At least one output file must be specified Best, Kieran. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".