Automatically sync two audio recordings in python
I have now tested Allison Deal's Video sync (also linked under "Update II" in the question) and it seems to do the job.
In the root of its git directory there is a file called "alignment_by_row_channels.py". If you comment in the test code at the end of that file, it can take two mp4 videos and print the time offset between the audio in the two videos.
I tested it with a Canon HF200 video camera and an LG G2 android phone, with talk and finger snaps and very low volume on the video camera. I then manually analyzed the sound tracks with audacity.
The alignment_by_row_channels.py script indicated an offset between the two track of 15.1893 seconds. My manual analysis by looking at waveforms gave 15.181 seconds (audacity does not output less than millisecond resolution, at least not by default).
The difference is only 8.3 milliseconds or thereabouts which seems to indicate that "alignment_by_row_channels.py" does the job.
(Beware that the git repo is hefty, probably due to deleted big objects)