blindbunny <[email protected]> added the comment:
Without trying to be overly annoying, I'll re-state this issue in the hope to clarify the problem. With the input file provided on upload.ffmpeg.org, ffmpeg inevitably scales down the 1080p stream in the file without being told to. Thus, the command #> ffmpeg -y -i /tmp/misscaling-video.m2ts -vcodec ffv1 -an -sn /tmp/output.mkv -map 0:0 turns the stream Stream #0.0[0x1011]: Video: h264, yuv420p, 1920x1080 [PAR 1:1 DAR 16:9], 23.98 tbr, 90k tbn, 47.95 tbc into the stream Stream #0.0: Video: ffv1, yuv420p, 720x480 [PAR 40:33 DAR 20:11], q=2-31, 200 kb/s, 1k tbn, 23.98 tbc instead of a stream with a 1080p resolution, as one would expect. I was not able to avoid this scaling. Thus, ffmpeg is unable to process this video stream correctly. It seems to me that ffmpeg gets confused by other video streams in the input file with a resolution of 720x480 and thus somehow feels compelled to automatically apply a scaling filter. (I did not repeat the full ffmpeg output here since it is equivalent to my previous postings sans the crop filter which only served to highlight the problem as it aborts ffmpeg before output is produced). I hope this helps in reproducing the problem and finding its cause. ________________________________________________ FFmpeg issue tracker <[email protected]> <https://roundup.ffmpeg.org/issue2156> ________________________________________________
