Thread: mplayer_1.0rc1-maemo.25
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Serge is offline Serge
2008-02-26 , 07:22
Posts: 503 | Thanked: 267 times | Joined on Jul 2006 @ Helsinki
#27
Originally Posted by andy1 View Post
I have just one question about the new lavdopts lowres=1,2 etc. Is mpeg2 really so processor intensive that mplayer cannot decode normal dvb-t stream even with lowres=2, I tried to stream direct mpeg2 stream from my homecomputer to n800 but it couldn't keep up no matter how low resolution I made the video and
One of my goals of adding a working lowres decoding was DVD playback without transcoding. Now lowres=1 option just works (it did not with the previous release), but it saves only ~10% of cpu power, though the number of pixels to process got 4x smaller. In order to get the best performance, more ARM optimizations are required: lowres 4x4 IDCT, lowres motion compensation functions, etc. AC3 audio decoding is important for DVD playback, that's why I'm also adding some VFP optimizations which should pay off later.

I also tried to play part of the stream directly from memorycard so the wlan wasn't the bottleneck.
Actually WLAN is the bottleneck for high bitrate video such as DVD to a much higher extent than the decoder. I'm also hacking WLAN driver for Nokia 770 (just because official development stopped for it and we will not be stepping on each other toes) to see if its performance can be improved and cpu overhead reduced. The results are *very* promising: http://www.internettablettalk.com/fo...ad.php?t=12787