Why Can't R4 Cards Play .avi Files?

Discussion in 'R4 DS' started by mbcrazed, May 9, 2014.

  1. mbcrazed
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    mbcrazed GBAtemp Advanced Fan

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    I've been wondering this for quite some time. It's such a struggle to find a way to convert them to dpg!
     
  2. Cartmanuk

    Cartmanuk GBAtemp Advanced Fan

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    AVI (Audio Video Interface) is a multimedia container format. An R4 card is a flash-based Nintendo DS storage device that supports video files. R4 users who want to view their AVI files on their systems can convert their files to DPG, an R4-supported video format, with a third-party software program, such as Batch DPG, Leawo DPG Converter, and Almersoft AVI to DPG Converter
     
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  3. FAST6191

    FAST6191 Techromancer

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    Technically they can play avi files via homebrew (see tunavids or its predecessors), just the requirements of the video and audio the avi file has to contain (though avi is very limited it is still a container and can contain several different formats) are rather harsh.

    Short version is the DS is very weak hardware and can not decode the average avi file (read scene avi file) in real time. The DSTwo, iSMM, iplayer and everything else (Nintendo had some stuff back on the GBA at least, not sure what Datel's media player stuff did exactly) tends to have its own video decoding hardware (or hardware that can be turned to video decoding) onboard which is used instead. If it plays from the menu then chances are the teams used moonshell's source code to do it.

    DPG is just a tweak on an even older format called MPG (MPEG1), however it had some benefits for being custom so we have the custom format DPG instead. There are a couple more formats others tried on the DS, including the interesting wavelet based encoding for DSvideo.
     
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