Talk:Video: Difference between revisions

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== Recommended formats? ==
== Recommended formats? ==
This page needs to tell content providers how best to format their videos for the XO. Should they use Ogg Theora? What framerate, resolution, number of colours, quality level etc?--[[User:Tomhannen|Tomhannen]] 06:09, 18 November 2007 (EST)
This page needs to tell content providers how best to format their videos for the XO. Should they use Ogg Theora? What framerate, resolution, number of colours, quality level etc?--[[User:Tomhannen|Tomhannen]] 06:09, 18 November 2007 (EST)

: See [[Theora]] it's upcoming soon. See [[Speex]] for voice based audio. [[User:Sethwoodworth|is for Insects]] 01:46, 2 December 2007 (EST)

== Practical Test Results ==
I've found that Theora works well at 320x240 and 600 to 750 kbps. Above that bit rate, it misses occasional frames. At 640x480 (any bit rate) video is like listening to a radio play with occasional still photos flashing by. At least, all of this is true for short clips.

For larger movie files (half an hour - about 175 MB) the Browser activity never finishes loading, and Watch & Listen loads but fails to play. Copying such files between journals on different drives causes the Journal activity to hang and shutdown to go badly. After this happened to me the XO was bricked, so I had to re-flash it. So support for large video files still needs work. Maybe it's trying to load the whole thing into limited RAM? [[User:Bouncey|Bouncey]] 20:58, 5 January 2008 (EST)

Further tests: Dropping the video and audio bit rates so that same half-hour show is about 43 MB, Browser still refuses to load. Most of the problems with bigger files seem related to activities making multiple copies of large files loaded from SD card into a data store on internal flash (but then what's the point of having an SD card?), but that doesn't explain this. I might have to start digging through the bug tracking system... From tests on my Mac, I'm surprised at how good video clips can look in spite of very low resolution and bit rate. [[User:Bouncey|Bouncey]] 02:12, 6 January 2008 (EST)

Latest revision as of 07:12, 6 January 2008

Recommended formats?

This page needs to tell content providers how best to format their videos for the XO. Should they use Ogg Theora? What framerate, resolution, number of colours, quality level etc?--Tomhannen 06:09, 18 November 2007 (EST)

See Theora it's upcoming soon. See Speex for voice based audio. is for Insects 01:46, 2 December 2007 (EST)

Practical Test Results

I've found that Theora works well at 320x240 and 600 to 750 kbps. Above that bit rate, it misses occasional frames. At 640x480 (any bit rate) video is like listening to a radio play with occasional still photos flashing by. At least, all of this is true for short clips.

For larger movie files (half an hour - about 175 MB) the Browser activity never finishes loading, and Watch & Listen loads but fails to play. Copying such files between journals on different drives causes the Journal activity to hang and shutdown to go badly. After this happened to me the XO was bricked, so I had to re-flash it. So support for large video files still needs work. Maybe it's trying to load the whole thing into limited RAM? Bouncey 20:58, 5 January 2008 (EST)

Further tests: Dropping the video and audio bit rates so that same half-hour show is about 43 MB, Browser still refuses to load. Most of the problems with bigger files seem related to activities making multiple copies of large files loaded from SD card into a data store on internal flash (but then what's the point of having an SD card?), but that doesn't explain this. I might have to start digging through the bug tracking system... From tests on my Mac, I'm surprised at how good video clips can look in spite of very low resolution and bit rate. Bouncey 02:12, 6 January 2008 (EST)