(Feature Request) Support for more video formats (Such as WMV)

[dangerousd777]

Is it possible for Rockbox on the Sansa e200 to decode and render any other files other than Mpeg-1 and Mpeg-2? I know Mpeg-4 probably isn't possible since the CPU isn't very fast (30 mhz, automatically clocks up to 80 mhz as you can see in debug, as well as shows how many clock cycles per second it takes to decode and render audio files. You can change the boost counter in frequency to 1 (from 30-80 mhz or down from 30-24 mhz and that makes it much faster with jpeg decoding and demos.). WMA typically tends to be a lower resource intensive format so I wonder if WMV is similar.
 
Just wondering, because right now I'm using Mpeg-1 and it is decent but the compression/quality is no where near as good as XviD or anything.

If you could do it, like WMV with WMA audio, then it would be a kind of godsend... I'm serious, the file size at 220x176 would be very small and the quality would be pretty good. WMA sounds decent at about 64-96 kbps (while WMA 9 [10 pro] and ogg vorbis sound fine at as low as 32 kbps), it would be the same to decode yet less to render compared to higher bitrate audio, and certainly less intensive than Mp3.

Mpeg-1 and Mpeg-2 are limited to about 23.97 FPS at minimum, WMV could go much lower but only around 15 FPS would be tolerable... but it might be a matter of limitations with the CPU and decoding, maybe even other things as well.

[saratoga]

We'd like to see other formats, however anything slower then MPEG2 isn't likely to work well on your sansa. 

[dangerousd777]

True, the solution for that may be to use a lower framerate, less complex audio stream such as WMA, simpler video conversion profile and lower resolution.

In the meantime while we all think about this I'll find a way to measure the CPU usage of decoding different video formats, the only thing is the results may be a bit subjective due to the decoder used (I probably will be using FFDShow).
Nevertheless, there are PLENTY of different video formats to test out, some may be only slightly more or less intensive than Mpeg-1/2, however the more compressed the more likely that won't be so.

[soap]

True, the solution for that may be to use a lower framerate, less complex audio stream such as WMA,

This is the second time you have suggested WMA is less CPU intensive to decode.
See here.  (WMA decoding on the iPod Video should be the same as on your Sansa).
Even before saratoga split MP3 decoding onto both cores, nearly doubling its speed, it was faster than WMA.  Now it stomps all over it.

[dangerousd777]

True, the solution for that may be to use a lower framerate, less complex audio stream such as WMA,

This is the second time you have suggested WMA is less CPU intensive to decode.
See here.  (WMA decoding on the iPod Video should be the same as on your Sansa).
Even before saratoga split MP3 decoding onto both cores, nearly doubling its speed, it was faster than WMA.  Now it stomps all over it.

MP3 surely is the one to use then.

I wonder about a comparison of the video formats. Most but maybe not all compressed formats are slower than Mpeg 1/2, I wonder however if there are any formats offering better quality/size and the same speed, unlikely however. With WinFF though I don't think I need to worry so much anymore, the video compression is great with 2-pass and bitrate between 125-400 based on scene complexity.

[saratoga]

Probably not.  The CPU/compression trade off is fundamental in video codecs.

[dangerousd777]

FLAC is the least, Mp3 is close...

I use Ogg Vorbis, because it offers excellent compression. It might be shortening my battery life, but I don't mind I don't use it for very long. The Sansa went through 2 days of heavy usage and then finally the battery died and it only took 2 hours to charge.

If anything, I think Mpeg-2 works fine, not the greatest compression/quality you would expect, but it works good enough compared to my other Mp4 player which used .SMV (Motion Jpeg like format + IDA ADPCM WAV audio) and the compression, quality, and conversion speed was absolutely TERRIBLE.

Mpeg is VERY VERY FAST