Meaning of ffmpeg output (tbc, tbn, tbr) [closed]

Question

I am using ffmpeg to tell me video info. Specifically:

ffmpeg -i video.ext

I get the output:

Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 704x576 [PAR 12:11 DAR 4:3], 9578 kb/s, 25 tbr, 90k tbn, 50 tbc

Does anyone know what tbr, tbn and tbc are exactly? I have seen speculation on the net but nothing definitive?

Answer 1

Well it's all about time. FFMpeg uses in fact three different timestamps in different bases in order to work.

• tbn = the time base in AVStream that has come from the container
• 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

This was also asked on the FFmpeg mailing lists: What does the output of ffmpeg mean? tbr tbn tbc etc?