[mythtv-users] Joining MP4s

[Peter Bennett]

On 1/31/23 10:10, James wrote:
> I recorded a movie that I want to save. Due to the whims of the Australian Open my 20 min post record failed by 2 minutes. Playing Amazon Prime in a VM I screen captured the last 2 min of the movie..
>
> I now have my movie-2min with commercials cut stored as a 'Movie' It plays perfectly.
> I have the last 2 minues as a clip. It too plays perfectly.
>
> Each is 720x576 16:9 24.99 Hz. Both are h264 in a mp4 container. The OTA recordings are interlaced.
>
> How on earth can I append the end.mp4?
>
> I tried shotcut which re-rendered giving perfect video but lip sync of 500ms variable, with the end clip in sync
> I tried mythffmpeg which muddled everything ie repeated sections general chaos
>
> mythffmpeg -f concat -safe 0 -i /store/TScut_work/file -c copy /store/Movies/Myth-V/Thur\ Vow.mp4
>
> Any experts with handbrake et al
>
> Of interest *some* OTA 720 and 1080 videos maintain lip sync, some do not. I've not looked why I occasionally shotcut a snip to put the MOV atom at the front of the file for downloads.
>
> EG http://tigger.ws/downloads/qna.mp4
>
> James
> _______________________________________________

I use mkvmerge, which can split and append, as long as the parts use the 
same tracks, resolution, etc. It reads any type of input and creates an 
mkv file. mkv files can be played by most players including mythtv. You 
can also adjust the audio sync if necessary. I have used it for editing 
out the commercials in a show, by splitting and joining parts.

Peter