Video: Difference between revisions

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The [[Theora]] codec is recommended for video playback.
The [[Theora]] codec is recommended for video playback.
*You can encode Theora files using the commmand line [http://v2v.cc/~j/ffmpeg2theora/download.html ffmpeg2theora ffmpeg2theora]] application .
*You can encode Theora files using the commmand line [http://v2v.cc/~j/ffmpeg2theora/download.html ffmpeg2theora] application .
*[http://commons.wikimedia.org/wiki/Help:Converting_video Information on theora video conversion.]
*[http://commons.wikimedia.org/wiki/Help:Converting_video Information on theora video conversion.]
*The free media player [http://www.videolan.org/vlc/ VLC] can also encode theora files. Follow [http://www.videolan.org/vlc/download-fedora.html fedora 7 instructions] for installing VLC and helper applications on the XO laptop.
*The free media player [http://www.videolan.org/vlc/ VLC] can also encode theora files. Follow [http://www.videolan.org/vlc/download-fedora.html fedora 7 instructions] for installing VLC and helper applications on the XO laptop.
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*http://www.archive.org/ A place to download and upload CC video and audio clips in native ogg/theora format.
*http://www.archive.org/ A place to download and upload CC video and audio clips in native ogg/theora format.
*http://ourmedia.org/ Similar to archive.org.
*http://ourmedia.org/ Similar to archive.org.
*http://wiki.xiph.org The Xiph.org wiki has long lists of streaming Ogg/Vorbis and online Ogg/Theora content. I just finished verifying and adding sources, so it is all be up to date, as of 2008-08-25.


== Streaming video over the laptop network ==
== Streaming video over the laptop network ==
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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.
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 ==
== Videoconferencing ==
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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.
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.
vieo blue appel actvidad


== Todo ==
== Todo ==
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=== Elephant's Dream ===
=== Elephant's Dream ===
The canonical free-content demo video, created entirely with free tools, primarily [[Blender 3D]], and available in a dazzling array of resolutions, frame rates, and encodings. We use an mpeg version for our full-screen video [[demonstration build|demo]].
The canonical free-content demo video, created entirely with free tools, primarily [http://www.blender.org Blender 3D], and available in a dazzling array of resolutions, frame rates, and encodings. We use an mpeg version for our full-screen video [[demonstration build|demo]].


=== Movies ===
=== Movies ===

Latest revision as of 20:36, 20 March 2010

  english | 한국어 HowTo [ID# 233621]  +/-  


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.

See Speex for voice-based audio.

Video/audio archive sites

  • http://www.archive.org/ A place to download and upload CC video and audio clips in native ogg/theora format.
  • http://ourmedia.org/ Similar to archive.org.
  • http://wiki.xiph.org The Xiph.org wiki has long lists of streaming Ogg/Vorbis and online Ogg/Theora content. I just finished verifying and adding sources, so it is all be up to date, as of 2008-08-25.

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 (Are 2-min video clips small enough to be buffered on-XO in their entirety?) and hopefully streaming video from server to XO (Up to 30-minute long 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. vieo blue appel actvidad

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.
  2. Figure out how said streaming works with local cache -- if you're streaming an hour-long video, avoiding overwhelming memory or disk.
  3. 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.)



Interesting video content

Recordings from children

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


How can we upload videos the children make? Please email me the answer. Please be specific:-) Also the video isn't very good quality at all when it's played back, anyway to improve that. The pictures are great though!

Thank You, Listen, olpc@goct.net
Visit this wiki, log in, and follow the "upload file" link on the left hand sidebar. That will let you upload an image from your Journal... then you need to write something about where the image was taken from, and include it in a page on this wiki. --Sj talk 17:20, 21 June 2008 (EDT)

Elephant's Dream

The canonical free-content demo video, created entirely with free tools, primarily Blender 3D, and available in a dazzling array of resolutions, frame rates, and encodings. We use an mpeg version for our full-screen video demo.

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 films from the online PD film sites

Television

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