Keep audio from source file

[mifi]

No description provided.

[chapmanjacobd]

maybe the default can be to take only video from the source file but if someone wanted the audio from the clips by default then they could do this:

edit: I made some improvements on this interface in: #30

[mifi]

Yea, something like that. I just need to implement concatenation (and maybe fading) between videos audio clips too. It's not super trivial but it should be doable.

[chapmanjacobd]

I was just playing around with concat last night. not sure how helpful this is:

https://gist.github.com/chapmanjacobd/7b6849c68dc78eb7679c7c639c64b9ae

a fading option would be awesome!

[mifi]

Yea something like that. Problem is that if there is 1 too many video frames or one missing, or if audio or video duration is wrong, then audio will go out of sync, especially after many clips.

[chapmanjacobd]

hmmmm what if we render audio and video under separate processes and then merge them together afterword? I think this is how youtube-dl works

edit: maybe that doesn't solve the issue exactly :/ I'm not really sure what options we have here

[mifi]

Yes we can use ffmpeg concat and output to separate files. Just need to figure out what to do with audio in transitions. I think cross-fade is the right way. Basically need to implement a similar loop to the audio data as the video loop. but instead of gl-transition, need to use a simple mathematical operation between in and out audio.

As a simple first version we could just concat all audio files (but need to cut off transition.duration seconds off of the end of every audio clip), and need to provide silent audio when video clip has no audio, or there is no video layers in a clip.

[chapmanjacobd]

https://stackoverflow.com/questions/32155105/crossfading-html5-audio-logic

we can actually do audio crossfade inside of ffmpeg

https://stackoverflow.com/questions/47437050/crossfading-between-two-audio-files-with-ffmpeg

also check out: #30 (comment) I updated this interface to make more sense. let me know what you think

[SurinameClubcard]

I would love to see this feature added. I just merged a couple of videos only to find out afterwards that the original audio of the clips was removed. Had to use OpenShot again to do the merging. Declarative is sooooo much nicer... :-)

[mifi]

This is now implemented, but without cross fade yet. 0.5.0
You must use the flag --keep-source-audio or keepSourceAudio: true. See readme.