On 11/7/14, George Chriss gschriss@gmail.com wrote:
On Tue, November 4, 2014 5:55 pm, Brion Vibber wrote:
Hmm, is Motion-JPEG no longer a thing, or does it not scale to the quality or bitrates needed nowadays? Used to be pretty standard back in the days I was fiddling with video editing 10-15 years ago (MJPEG would be packaged usually in .avi or .mov depending on the platform's preferred video container).
Motion-JPEG is a thing to the extent that IP cameras deliver JPEG-over-RTSP/RTP -- a fair number of cameras on-market do, others do on-the-fly MP4 streaming, and some do both. Thus, saving the incoming M-JPEG stream is means of (virtually) lossless recording. Likewise if you have HW acceleration available to do on-the-fly JPEG conversion from raw bayer recording modes.
The LibrePlanet 2013 videos hosted on media.libreplanet.org were recording in JPEG+Vorbis-in-Matroska (18FPS) then converted to WebM for upload. There's no corresponding container binding I'm aware of for JPEG-in-Ogg but in theory this can be done without much fuss. In any case the video/editing quality, command-line tools, and patent status (IANAL) is really quite suitable for use in the free software community but widespread adoption is another issue altogether. The format also works well within Pitivi.
There's arbitrary JPEG-in-Matroska upload restrictions on popular video hosting services: the backend ffmpeg binary is able to decode and convert just fine but the format hasn't been explicitly whitelisted due to _______. I would be happy to see JPEG-in-Matroska adoption by the WMF and community.
Sincerely, George
I think it would make sense to enable mkv contained video, limited to free codecs. In addition to MJPEG, there is also FFV1 (which based on my googling) is a lossless codec serving a similar niche as MJPEG2000 (and hence MJPEG and "mox" maybe?), but also starting to gain some popularity in the video archiving world (If "edit retention" is the magic trigger word for getting things done on wikipedia, "glam" is probably the magic word for getting stuff done related to media, albeit not anywhere near as strongly).
The only issue is that mkv can also be used for non-free codecs [1], so from a usability prespective it might confuse users if only some mkv files are allowed (I wish people would use a unique extension for each <container, video codec, audio codec> triple, make life so less confusing).
--bawolff
[1] http://www.matroska.org/technical/specs/codecid/index.html