James REGIS wrote:
Thansk a lot now I can grab up to 25 ~30 fps ...
I'm sure many would be interested to know which of the tips given
worked. Could you please post what hardware you're using, what grab
tool, and the parameters used?
Do you have a method to display the grabbed frame on screen with 25 fps ??
Thanks Again
Depends on the format used to save the frames! mplayer (
www.mplayerhq.hu ) can play a wide variety of formats.
At 10:46 09/07/2003 +0200, vous avez écrit:
James REGIS wrote:
hi,I am make program to capture from v4l device, when I use 640x480,
it can't do 12.5 frame per second,this speed is common, with 320x240,
it also do 12.5 fps,it's too slow, why? I compare with the fbtv in
console mode, 640x480 it can do 12.5 fps, the same as mine, but with
resolution 320x240,it can do 24~25 fps, the source code of fbtv is
fairly complex and now I have no much time to read it. can anyone
give me a sugguest to improve the capture speed! I attache my code
for ref .thanks!
Many cards are slower as soon as you dont use the standard size
704x576 and/or the preferred pixel format (usually YUV420P) I have no
problems grabbing 25fps at this size and format *provided* the code
uses the multi-buffer, interleaved capture as described in the
"Programming-FAQ" that comes with the xawtv distro. *Then* I do the
scaling, cropping, etc by software.
--
Michel Bardiaux
Peaktime Belgium S.A. Bd. du Souverain, 191 B-1160 Bruxelles
Tel : +32 2 790.29.41
