Audio Alignment Implementation

Suggestion
36

I will try to migrate to Shotcut. :smiling_face_with_three_hearts:

Since I will be not using the automatic un-drifting and alignment through Shtocut’s UI until Monday, I shall use the following hack. I’d love to get some help from MLT gurus
 :sweat_smile:

I have written a script that generates an mlt file, just like @brian mentioned.

The script uses the “drift and alignment calculator” and then executes something like

melt -profile atsc_1080p_60 file.mp4 -track -blank 78 file.wav -consumer xml
to generate the “.mlt” file. I will include this mlt file instead of file.mp4 and file.wav.

However, I do not know how to instruct melt to apply the “drift”. It seems I need to use -chain and -link. I want to apply those to file.wav, without applying it to -blank 78. I suppose it is something like this:

melt -profile atsc_1080p_60 file.mp4 -track -blank 78 -chain file.wav -link timeremap speed=0.9995 -consumer xml

The values 78 and 0.9995 are determined by the program I wrote.

So, does any one know the proper way to instruct melt to generate this “aligned and undrifted” mlt file?

Actually, I’d also like to suppress file.mp4’s audio
 :pray: :grin: