Video

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The article is about video running on the OLPC laptop. There is also Video of the OLPC project, laptop, etc.

Recommended codecs

The Theora codec is recommended for video playback. You can encode Theora files using the commmand line application [ffmpeg2theora]. [VLC], the free media player software can also encode theora files.

See Speex for voice based audio.

Streaming video over the laptop network

We want to be able to store video on school servers [finding the right address/location], and stream it from them. We want to support recording video from XO to server, viewing video from server to XO (2-min video clips large enough to be buffered on-XO in their entirety) and hopefully streaming video from server to XO (30-minute videos).

Large video files

One large media provider for this test has sent us 600G of video, with more coming tomorrow, for use in countries month. A copy of the video is going to Real, who are trying to get streaming to work as well; but it would be great to have theorur (for instance) working and streaming .ogg for us. Hopefully Juba can be of assistance here.

Videoconferencing

http://blog.printf.net/articles/2006/12/19/olpc-videoconferencing

Excerpts from #olpc regards http://blog.printf.net/articles/2006/12/19/olpc-videoconferencing : we have a video-call-activity, it's just not ready yet, needs extra support from Tubes. codec is h.263. I think we got h.263 from ffmpeg, which isn't shippable. (it's a bunch of GPL code for implementing patented and strongly-enforced algorithms.) ffmpeg as a whole isn't shippable, but h.263 probably is. It was released in 1995, and was in development well before then, so most patents have probably expired. yeah; and if they haven't expired, I've heard no-one's really interested in enforcing them anymore. It's all about h.264 now. so perhaps it would be worthwhile to create libh263. but we'd probably want legal advice first.

the camera driver supplies userspace with a YUV422 stream directly, if requested, without using the CPU for conversion. and I think the LX's graphics processor does YUV -> RGB, too.

I believe I also saw mention of a higher performance theora video encoder being in development, but not yet released. MitchellNCharity 22:28, 30 September 2007 (EDT)

We can and should ship ffmpeg. Besides h.263, of which I know nothing, ffmpeg includes useful codecs like snow and mjpeg. AlbertCahalan 00:19, 1 October 2007 (EDT)

Lots of the video frame will be unused, and can be cropped away before compression. A movable 256x320 window would be decent. Default to having it where a kid's head is most likely to be located. AlbertCahalan 02:26, 1 October 2007 (EDT)

Video activity

There is a draft activity which records video and can play video back. It doesn't support streaming at the moment, because of troubles getting Theora to stream. MJPEG may be a less computationally intensive choice.

Todo

1. Get Theora streaming over a school server in a way that works from an XO browser. Talk to Juba about theorur for this.

1. Figure out how said streaming works with local cache -- if you're streaming an hour-long video, avoiding overwhelming memory or disk.

1. Define the recommended max size and max bitrate for video (easy if we're not streaming; for streaming, worry about local caching and network throughput.)

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Interesting video content

Recordings from children

• Recordings from the XO camera
• Recordings from an external camera plugged in via USB

Movies

• the Qatsi trilogy: Koyaanisqatsi, et al

  The creator and director has expressed interest in sharing some of these works, and of his Anima Mundi short

• Baraka
• Old b&w film

Television

• Science: Cosmos, Nova
• Sesame Street and localizations
• Music
• Mr. Roger's Neighborhood