My question comes down to how they're stored. [Obviously] I'm not an expert on video encoding or containers.
FLV is a container, yes? Usually, I'm guessing, MP3 and H.264. H.264 works out well for youtube because they can then also use this on their HTML5 video players.
So are the H.264 blobs and the mp3 blobs stored as discrete files, then packaged when a video is loaded and sent down the tubes? If so, then yeah, obviously, it would be really easy or youtube to serve "audio only"; probably "a few lines of code".
But if the MP3 and H.264 (again h.264 is an assumption) are stored as one [flv] package, they would have to be unpacked before being able to be sent down as their individual components.
Again, this is a shortcoming in my understanding of video containers, so maybe I'm missing the point on this completely. (As in: maybe "unpacking" an FLV is trivial)
FLV is a container, yes? Usually, I'm guessing, MP3 and H.264. H.264 works out well for youtube because they can then also use this on their HTML5 video players.
So are the H.264 blobs and the mp3 blobs stored as discrete files, then packaged when a video is loaded and sent down the tubes? If so, then yeah, obviously, it would be really easy or youtube to serve "audio only"; probably "a few lines of code".
But if the MP3 and H.264 (again h.264 is an assumption) are stored as one [flv] package, they would have to be unpacked before being able to be sent down as their individual components.
Again, this is a shortcoming in my understanding of video containers, so maybe I'm missing the point on this completely. (As in: maybe "unpacking" an FLV is trivial)