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I wasn't expecting much going in but that was a great read. Hearing quicktime turned me off but it's actually an interesting format from this articles descripti

I wasn't expecting much going in but that was a great read. Hearing quicktime turned me off but it's actually an interesting format from this articles description. Obviously proprietary formats with not many open source parsers is the biggest issue, but still a neat idea to think about.

CharlesW 3y ago
The QuickTime Movie container format became ISOBMFF (https://en.wikipedia.org/wiki/ISO_base_media_file_format https://en.wikipedia.org/wiki/ISO_base_media_file_format), which is open, and so happily has lots of open source support.
- koito17 3y ago
  Not to mention, it's always been easy to access the QuickTime File Format Specification, and I have seen it being used all the time by people wanting to implement MP4 (de)muxers but not having the money to buy overpriced ISO specifications or effort to hunt around for drafts of MPEG-4 Part 14. There are subtle differences in how you should lay out some atoms (e.g. ftyp is subtly different in QuickTime, MP4 uses free instead of wide atom, some Macintosh-specific fields in vmhd(?) and related atoms are always zeroed out and marked as "reserved" in MP4, etc.). But it's easy to gloss over these differences when you do not care about the Macintosh-specific things (like QuickDraw transforms, sprites, ...)
eschaton 3y ago
Thanks! QuickTime’s not proprietary, it’s been well-documented and open since it was new and being 30+ years old there’s not a lot of encumbrance to worry about.
dylan604 3y ago
The QuickTime container has a lot of unused capabilities. At one point, you could add a Flash track to an MOV that could control the audio/video tracks. At the time, there was a lot of DVD like MOVs where it would switch audio tracks to commentaries or other languages. You could switch to a different video track like angles. The format might be nasty thing to try to parse, but it could do a lot more than just hold a set of video/audio streams.
- eschaton 3y ago
  One great thing about this is that the Flash support isn’t a feature of the QuickTime container format—it’s just another type of track media! The container or overall structure didn’t have to change to accommodate it, it could just be added in like one more CODEC.

CharlesW 3y ago

The QuickTime Movie container format became ISOBMFF (https://en.wikipedia.org/wiki/ISO_base_media_file_format https://en.wikipedia.org/wiki/ISO_base_media_file_format), which is open, and so happily has lots of open source support.

koito17 3y ago
Not to mention, it's always been easy to access the QuickTime File Format Specification, and I have seen it being used all the time by people wanting to implement MP4 (de)muxers but not having the money to buy overpriced ISO specifications or effort to hunt around for drafts of MPEG-4 Part 14. There are subtle differences in how you should lay out some atoms (e.g. ftyp is subtly different in QuickTime, MP4 uses free instead of wide atom, some Macintosh-specific fields in vmhd(?) and related atoms are always zeroed out and marked as "reserved" in MP4, etc.). But it's easy to gloss over these differences when you do not care about the Macintosh-specific things (like QuickDraw transforms, sprites, ...)

eschaton 3y ago

Thanks! QuickTime’s not proprietary, it’s been well-documented and open since it was new and being 30+ years old there’s not a lot of encumbrance to worry about.

dylan604 3y ago

The QuickTime container has a lot of unused capabilities. At one point, you could add a Flash track to an MOV that could control the audio/video tracks. At the time, there was a lot of DVD like MOVs where it would switch audio tracks to commentaries or other languages. You could switch to a different video track like angles. The format might be nasty thing to try to parse, but it could do a lot more than just hold a set of video/audio streams.

eschaton 3y ago
One great thing about this is that the Flash support isn’t a feature of the QuickTime container format—it’s just another type of track media! The container or overall structure didn’t have to change to accommodate it, it could just be added in like one more CODEC.