3 ms·

Google already maintains a large number of copies of YouTube videos, one for each quality level and now they've been adding h.264 and they may have some special

by cracell 17y ago

DarkShikari 17y ago
Google already maintains a large number of copies of YouTube videos, one for each quality level and now they've been adding h.264 and they may have some special ones for different devices I don't know about. Asking for one more in a codec that they own is not much to ask. Not quite true. They have the following from what I've seen: 1) fmt=6 FLV with ffmpeg ~350kbps (legacy) 2) fmt=18 H.264 Baseline ~500kbps, now with x264 (iPhone support + current default) 3) fmt=22 720p H.264 High with x264, ~2.2mbps 4) fmt=somethingorother 1080p H.264 High with x264, ~4.5mbps Note that options 3) and 4) don't exist for the vast majority of videos, and thus likely don't cost much disk space. Option 1) is being phased out. Their primary default is 2), a single format that works in Flash, on iPods, on iPhones, and on many mobile devices. They could have saved 30-50% on bandwidth by offering an H.264 High stream for PC viewers, but they didn't because it would have required they keep around a separate stream. Any argument that Youtube should keep around a separate format for some Purpose X has to confront the fact that Google has thrown away staggering quantities of bandwidth explicitly to avoid offering a separate format.
- blasdel 17y ago
  Is it correct that (1) is VP6, not h.263?
  - DarkShikari 17y ago
    No, it's H.263. As far as I know, Youtube never used VP6. See http://news.ycombinator.com/item?id=1132933 http://news.ycombinator.com/item?id=1132933 for some possible reasons why.
    - blasdel 17y ago
      Yeah, at least that has multiple independent implementations. All the On2 stuff just has the one, especially since they only ever released new incompatible codecs instead of improving their older products. Funnily enough that applies just as much to Theora (née VP3), which right now is a only an open standard in theory, not IETF-level reality. There's a few forks of the original On2 code and a transliteration of the decoder to Java for applets (Cortado). I guess people have been working on writing a new DSP decoder, but the whole thing feels like an even worse recapitulation of the ODF lie.
      - DarkShikari 17y ago
        This is IMO the core problem with proprietary-based "standards": even if the formats are opened, people rarely make independent implementations of them and bugs often persist for years before being found.
- vetinari 17y ago
  There are some more copies, for example: format 35: mp4/h264/aac, 480p@main format 34: flv/h264/aac, 360p@main format 5: flv/svq3/mp3, 400x226 format 36: 3gp/mpeg-4 asp/aac, 320x240 format 17: 3gp/mpeg-4 asp/aac, 176x144 format 13: 3gp/mpeg-4 asp/amr, 176x144
- PanMan 17y ago
  If you visit m.youtube.com you'll see they also offer .3gp files for mobile. If I'm not mistaken, even in some different resolutions.

by cracell 17y ago

DarkShikari 17y ago

Google already maintains a large number of copies of YouTube videos, one for each quality level and now they've been adding h.264 and they may have some special ones for different devices I don't know about. Asking for one more in a codec that they own is not much to ask. Not quite true. They have the following from what I've seen: 1) fmt=6 FLV with ffmpeg ~350kbps (legacy) 2) fmt=18 H.264 Baseline ~500kbps, now with x264 (iPhone support + current default) 3) fmt=22 720p H.264 High with x264, ~2.2mbps 4) fmt=somethingorother 1080p H.264 High with x264, ~4.5mbps Note that options 3) and 4) don't exist for the vast majority of videos, and thus likely don't cost much disk space. Option 1) is being phased out. Their primary default is 2), a single format that works in Flash, on iPods, on iPhones, and on many mobile devices. They could have saved 30-50% on bandwidth by offering an H.264 High stream for PC viewers, but they didn't because it would have required they keep around a separate stream. Any argument that Youtube should keep around a separate format for some Purpose X has to confront the fact that Google has thrown away staggering quantities of bandwidth explicitly to avoid offering a separate format.

blasdel 17y ago
Is it correct that (1) is VP6, not h.263?
- DarkShikari 17y ago
  No, it's H.263. As far as I know, Youtube never used VP6. See http://news.ycombinator.com/item?id=1132933 http://news.ycombinator.com/item?id=1132933 for some possible reasons why.
  - blasdel 17y ago
    Yeah, at least that has multiple independent implementations. All the On2 stuff just has the one, especially since they only ever released new incompatible codecs instead of improving their older products. Funnily enough that applies just as much to Theora (née VP3), which right now is a only an open standard in theory, not IETF-level reality. There's a few forks of the original On2 code and a transliteration of the decoder to Java for applets (Cortado). I guess people have been working on writing a new DSP decoder, but the whole thing feels like an even worse recapitulation of the ODF lie.
    - DarkShikari 17y ago
      This is IMO the core problem with proprietary-based "standards": even if the formats are opened, people rarely make independent implementations of them and bugs often persist for years before being found.
vetinari 17y ago
There are some more copies, for example: format 35: mp4/h264/aac, 480p@main format 34: flv/h264/aac, 360p@main format 5: flv/svq3/mp3, 400x226 format 36: 3gp/mpeg-4 asp/aac, 320x240 format 17: 3gp/mpeg-4 asp/aac, 176x144 format 13: 3gp/mpeg-4 asp/amr, 176x144
PanMan 17y ago
If you visit m.youtube.com you'll see they also offer .3gp files for mobile. If I'm not mistaken, even in some different resolutions.