[FFmpeg-user] the trim filter

[Paul B Mahol]

On Fri, Jul 5, 2024 at 7:29 PM Mark Filipak <markfilipak.imdb at gmail.com>
wrote:

> On 05/07/2024 07.54, Paul B Mahol wrote:
> > On Fri, Jul 5, 2024 at 2:09 AM Mark Filipak <markfilipak.imdb at gmail.com>
> > wrote:
> >
> >> On 04/07/2024 17.12, Paul B Mahol wrote:
> >>> Its in documentation: asetpts=N/SR/TB, assuming everything starts from
> 0,
> >>> so add it after each atrim.
> >>
> >> For both video & audio,
> >>     time_base=1/90000
> >>     start_pts=1048560
> >>
> >> So, there are 'silent' audio samples starting with the first video
> frame.
> >> I'm dropping 20.062
> >> seconds of video (i.e., 481 frames). I really don't know how I could
> >> rewrite audio PTSes to make
> >> that 20.062 seconds of audio to go away. I really think that's
> impossible.
> >> They have to be dropped,
> >> just as I am dropping the 481 video frames.
> >>
> >> Here's my trim commands for the first segment:
> >>
> >>
> >>
> trim=start_frame=481:end_frame=134047,atrim=start_sample=962962:end_sample=268360093
> >>
> >> Here's the interesting terminal output (slightly beautified):
> >>
> >> [Parsed_trim_1 @ 0000000000620040]
> >>    Media type mismatch between the 'Parsed_trim_1' filter output pad 0
> >> (video) and the
> >> 'Parsed_atrim_2' filter input pad 0 (audio)
> >>
> >> [AVFilterGraph @ 000000000061c7c0] Error linking filters
> >>
> >> Failed to set value
> >>    'split=2[i5][i6],
> >>    [i5]trim=start_frame=481:end_frame=134047,
> >> atrim=start_sample=962962:end_sample=268360092[o5],
> >>    [i6]trim=start_frame=138745:end_frame=246719[o6],
> >>    [o5][o6]concat=n=2'
> >> for option 'filter_complex': Invalid argument
> >> Error parsing global options: Invalid argument
> >>
> >
> > This is exact proof that your FFmpeg CLI skills are bellow flat absolute
> > zero. I'm wasting my and everyone else time replying to your questions.
>
> What do you see, Paul, that is wrong? I respect you and your knowledge,
> but because you cite no
> evidence, it reduces what you write to the level of opinion. Well, anyone
> can have an opinion, eh?
> If there are 100 opinions, then at least 99 of them are wrong, and perhaps
> all 100 are wrong.
>
> I've given up trying to cut on IDR-frames because I don't know how to find
> which frames are
> IDR-frames and FFmpeg is not helping with that task. So, I'm decoding
> video & audio to pictures &
> samples and doing the trimming in those decoded domains. An error
> statement like "Failed to set
> value" tells me nothing. So, I come here...
>
> ffmpeg-user is intended to help users to succeed with FFmpeg. Well,
> trimming and splicing is
> important, wouldn't you say? So, what's wrong with my -filter_complex?
>

Try this freeware little tool:

https://github.com/richardpl/lavfi-preview


>
> --Mark.
>
>
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>