On 2021-02-26 16:53, Mark Filipak (ffmpeg) wrote:
…What I'm suggesting is that ffmpeg convert to a single, 360000Hz time base for all videos, for all time. Then, rounding errors would be *zero*. PTSs would be exact. …
As I told you back on 23. February, ffmpeg uses a timebase that is a rational number, and is an attribute of the video stream, and can take various values. The timebase could be 1/360000, or 1/24, or 1001/24000. This already allows integer Presentation TImestamp (PTS) values to represent time values with zero rounding errors. You dismissed that as "The Matrix", but this is in fact the data structure which FFmpeg already uses.
Of course, to achieve zero rounding errors, the input video, and the user writing the FFmpeg command line, and FFmpeg itself, must all make wise choices so that the timebase is set to a rational number which suits the data.
I don't think it is wise for FFmpeg to switch from its present flexible data structure to a constant, 1/360000 value for timebase. The examples you present do not make the case for such a change.
If you can establish that FFmpeg is imposing a 1/1000 timebase on a video with a 1001/24000 timebase, leading to rounding errors, that is evidence of a bug in FFmpeg's timebase calculation or something. It is not evidence of the timebase data structure being inadequate.
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