Can't link files if source media has timecode data about proxima

[in03]

This is still a problem unfortunately.

Some improvements:

• quicktime-style container instead of MXF, matches Resolve's internal proxy media metadata much more closely
• force-writing timecode instead of implicitly passing it

Some problems:

The Time code of first frame value that Resolve uses to check if the proxy media timecode matches is off by several frames between Resolve's own internal media and FFmpeg's encodes. Interesting here that FFmpeg timecodes actually match the source media's! Resolve's is off...

Potential Solutions:

• Find out more about Resolve's unusual timecode offset behaviour through BMD forums or BMD rep
• Analyse timecode data between Resolve and source over several files and see if there's a pattern we can apply to offset FFmpeg timecode data.

[in03]

Figured it out!

Under my nose the whole time.
The Start TC clip attribute matches Resolve's internally generated proxy media. We've been passing it around with the other clip attributes in media_list since forever. There are a few more attributes that may be of use to us too. There's probably no need to use FFprobe or MediaInfo at all now.

[in03]

Implemented Resolve TC in 572810e