Video Playback virtually impossible on Neo Freerunner? (Re: Video of Qt 4.4 on Neo1973: brings iPhone like graphics)

Tom Cooksey thomas.cooksey at trolltech.com
Mon Apr 28 18:14:44 CEST 2008


On Monday 28 April 2008 17:31:10 Mikko Rauhala wrote:
> On ma, 2008-04-28 at 09:26 -0500, Tim Shannon wrote:
> > But isn't it still limited by the bandwidth available from the micro
> > SD card?  Maybe I misunderstood that.  
> 
> Yes it is. It's just that sending mpeg4 packets to the glamo takes just
> a _tiny_ bit less bandwidth than sending entire uncompressed frames.

Huh?

I think (I hope) I've mis-understood you. Surely it depends what bitrate 
the mpeg4 video stream was encoded at? Personally I encode 640x480 
@ 25 fps at about 800 KBit/s for video. Uncompressed 16bpp would be:

640x480x25x16 = 120000 KBit/s

Surely 800 KBit/s is not just "a _tiny_ bit less" than 120000 KBit/s?


Sending compressed MPEG4 video to the glamo is going to be a _lot_
better than sending uncompressed fames!

I'm also wondering just _exactly_ what is meant by MPEG4. I'm guessing
it means MPEG4 part 2 - but which profile? Probably simple profile given
it's a mobile device - which probably means you'll have to transcode
all your videos to MPEG4 part-2 simple profile, as most MPEG4 video 
I've come across is Advanced Simple plus some codec-specific 
extenstions (Div.X seems to especially like defining their own extensions).
However, I believe this limitation affects IPods & PSPs, etc. too, so the 
neo is not alone.








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