According to the video encoding experts at Wolfram Research, mp4 footage always has to be re-encoded, not the case with MPEG2
I also found Kdenlive to be less than easy to use in the rendering area. On Wed, Oct 4, 2023, 7:23 PM Paul Boniol <[email protected]> wrote: > Definitely interested. > > One of the things I commonly do is take a video and cut out a few minutes > here and there. I'd love to have a way to do that (visually) without having > to reencode the entire video on output, but from my limited searching, I > haven't seen any software that does that. Maybe there is a technical > reason that isn't even possible. (Yes, I know it may have to create a new > key frame at the beginning of a cut but the entire video?) > > I've been using Kdenlive. It suffices, but figuring out parameters if you > want more control over the rendered output than "I want an mp4" is much > more difficult than it should be. (And at least one documented option > throws a big warning "this probably doesn't do what you think it does" if I > try to use it. And I still don't understand why the default value specified > isn't the value you see, or get... Just been living with it.) > > On Wed, Oct 4, 2023 at 4:57 PM Michael L <[email protected]> > wrote: > >> I'm up for it, after this coming Tuesday >> >> On Wed, Oct 4, 2023, 3:29 PM Vincent Brown < >> [email protected]> wrote: >> >>> Would any of you guys that are experienced at editing video & sound in >>> Linux consider doing some demos for an upcoming meeting. Doesn't >>> necessarily have to be next week's meeting. This would make a great topic! >>> >>> On Tuesday, September 19, 2023 at 9:49:52 PM UTC-5 [email protected] >>> wrote: >>> >>>> This is if you happen to know how far off the audio is from the video in >>>> this case 3840 milliseconds or 3.84 seconds >>>> >>>> >>>> *ffmpeg -i "movie.mp4" -itsoffset 3.84 -i "movie.mp4" -map 1:v -map 0:a -c >>>> copy "movie-video-delayed.mp4"*Found this here: >>>> https://superuser.com/questions/982342/in-ffmpeg-how-to-delay-only-the-audio-of-a-mp4-video-without-converting-the-au >>>> >>>> The hard part is knowing how far out of sync the audio is from the video, >>>> but it's a quick change of the command line to experiment. >>>> >>>> I generally like to avoid re-encoding the video as Gibson mentioned. >>>> Assuming you're not doing cinematography, a re-encode may give you more >>>> options. >>>> >>>> >>>> On Tue, Sep 19, 2023 at 9:32 PM Michael L <[email protected]> wrote: >>>> >>>>> I do video editing as part of my job. >>>>> Suggestion #1: The Shotcut video editor allows you to separate the >>>>> audio from video and add audio delay by moving the audio down the timeline >>>>> from the video by 1 frame at a time or more. That's a tough and >>>>> potentially time consuming way to get it exact, but maybe you can fix it >>>>> that way and re render / export the file. >>>>> >>>>> I'll search for another way with FFMPEG and let you know if I find it >>>>> .. along with other info. >>>>> >>>>> On Tue, Sep 19, 2023 at 6:35 PM Curt Lundgren <[email protected]> >>>>> wrote: >>>>> >>>>>> My brother sent me an MP4 file, about 900 MB, where the audio is at >>>>>> least a second ahead of video. I'd like to process the file so lip sync >>>>>> is >>>>>> proper, but my search engine fu is coming up short. ffmpeg seems like it >>>>>> would have the capability, but I haven't found a clue in the >>>>>> documentation >>>>>> or the man page. >>>>>> >>>>>> The video does not need to be changed in any way, but if possible, >>>>>> I'd like to boost the audio gain by as much as 10 db. >>>>>> >>>>>> I'd prefer to do this on a Linux machine, something running from >>>>>> command line would be ideal. Does anyone have a clue how this can be >>>>>> accomplished? >>>>>> >>>>>> Thanks >>>>>> Curt Lundgren >>>>>> >>>>>> -- >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "NLUG" group. >>>>>> To post to this group, send email to [email protected] >>>>>> To unsubscribe from this group, send email to >>>>>> [email protected] >>>>>> For more options, visit this group at >>>>>> http://groups.google.com/group/nlug-talk?hl=en >>>>>> >>>>>> --- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "NLUG" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/nlug-talk/CADPPtrp%3Dqnd%3DzFSQXAxjNfPQfZALp1RaXve0tpgt0fCsVTxhiA%40mail.gmail.com >>>>>> <https://groups.google.com/d/msgid/nlug-talk/CADPPtrp%3Dqnd%3DzFSQXAxjNfPQfZALp1RaXve0tpgt0fCsVTxhiA%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>> -- >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "NLUG" group. >>> To post to this group, send email to [email protected] >>> To unsubscribe from this group, send email to >>> [email protected] >>> For more options, visit this group at >>> http://groups.google.com/group/nlug-talk?hl=en >>> >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "NLUG" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/nlug-talk/52485163-e399-49c9-8dca-631eb7a8f95an%40googlegroups.com >>> <https://groups.google.com/d/msgid/nlug-talk/52485163-e399-49c9-8dca-631eb7a8f95an%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> -- >> You received this message because you are subscribed to the Google Groups >> "NLUG" group. >> To post to this group, send email to [email protected] >> To unsubscribe from this group, send email to >> [email protected] >> For more options, visit this group at >> http://groups.google.com/group/nlug-talk?hl=en >> >> --- >> You received this message because you are subscribed to the Google Groups >> "NLUG" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/nlug-talk/CALdmzXbJ6YMDVmVx%3DEvTROyZKsS%3DsZdUd9O82B3qs3JYsFmPdw%40mail.gmail.com >> <https://groups.google.com/d/msgid/nlug-talk/CALdmzXbJ6YMDVmVx%3DEvTROyZKsS%3DsZdUd9O82B3qs3JYsFmPdw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > -- > You received this message because you are subscribed to the Google Groups > "NLUG" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/nlug-talk?hl=en > > --- > You received this message because you are subscribed to the Google Groups > "NLUG" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/nlug-talk/CAL9PgS1rpyYBKoEvSY_pH1c%3DrxTJa%3DEHzKMd8v9hikVxo1ozLQ%40mail.gmail.com > <https://groups.google.com/d/msgid/nlug-talk/CAL9PgS1rpyYBKoEvSY_pH1c%3DrxTJa%3DEHzKMd8v9hikVxo1ozLQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- -- You received this message because you are subscribed to the Google Groups "NLUG" group. 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