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+--- Thread: Quicktime reference files - re-wrap - fps off (/thread-554.html)
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RE: Quicktime reference files - re-wrap - fps off - speedyrazor - 05.08.2018
Sure, I also noticed that in stream 0:0, the original has
25 fps, 25 tbr, 2500 tbn, 50 tbc (default)Where as the file I output is:
25 fps, 25 tbr, 12800 tbn, 25 tbc (default)Why is the tbn so wildly different, and can I hard set it somewhere?
Kind regards.
RE: Quicktime reference files - re-wrap - fps off - Selur - 05.08.2018
Quote:tbn = the time base in AVStream that has come from the containersource: http://www.ffmpeg-archive.org/What-does-the-output-of-ffmpeg-mean-tbr-tbn-tbc-etc-td941538.html
tbc = the time base in AVCodecContext for the codec used for a particular stream
tbr = tbr is guessed from the video stream and is the value users want to see when they look for the video frame rate
Before you mentioned:
Quote:The input file is 25fps, but my output file is 26.40fps,...but:
Quote:25 fps, 25 tbr, 12800 tbn, 25 tbc (default)would indicate that the output si 25fps not 26.4fps.
-> confused.
That aside you can set the tbn value for mov and mp4 files with 'video_track_timescale', so adding '-video_track_timescale 2500' might help. (hoping that this hasn't changed since the last time I used it
)Cu Selur
RE: Quicktime reference files - re-wrap - fps off - speedyrazor - 06.08.2018
OK, I got this working, but I cheated
I tried various versions of ffmpeg, and eventually found a working version from last year (3.2.4), which appears to produce the correct file.
The working command was simply:
ffmpeg -y -enable_drefs 1 -use_absolute_path 1 -i "P:/CSI/Test/CSP0002377.mov" -map 0 -c copy "P:/CSI/Test/test22.mov"
The output file is 25fps with no errors on output, tbn also correct.
Thanks for all your help Selur, as always, very helpful and knowledgable.
Kind regards.