-- Forgive me if this is a duplicate (trouble with email client, again) --
I think I can help out here, Vincent. On 11/02/2024 14.53, Vincent Deconinck wrote:
Hi, I will probably get flamed because I'm for jumping into this conversation while being a complete newbie :-), but I think nobody replied with an answer to Mark's question "why".
Before "why" there's the question of "should". I backed off "why" and am now simply trying to determine whether '-ss'-before-'-i' _should_ be the same as '-i'-before-'-ss'.
All I know is the ffmpeg page on seeking - https://trac.ffmpeg.org/wiki/Seeking - ends with a paragraph saying: "Using -ss as input/output option *together with -c:v copy might not be accurate* since ffmpeg is forced to only use/split on i-frames" (emphasis mine)
I split/trim _only_ on I-frames via '-ss value' in which 'value' has nanosecond resolution. I have confirmed that the trim PTSs are correct for '-ss'-before-'-i' but wrong by hundreds of frames for '-i'-before-'-ss'.
The page also states that: "As of FFmpeg 2.1, when transcoding with ffmpeg (*i.e. not stream copying*), -ss is now also "frame-accurate" even when used as an input option"
I am not transcoding.
My understanding is thus that with input seeking, the requested start time will not be satisfied without transcoding
Your quotation is "when transcoding with ffmpeg". It apparently doesn't apply to "without transcoding". I asked Should Command 1 and Command 2 make the same outputs? "Yes" or "No"? Arguing (or even citing) the so-called documentation is pointless. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
