2008-03-25 08:23:20 Click sound/noise while playing audio with jpeg
Zaahir Khan (INDIA)
Message: 53014 Hello,
We are using BF561 rev .5 using 1854 audio & 7179 encoder chips the board.
We are facing one problem while running mp3 & jpeg images togather , getting small click noise
roughly in gap of 8-10 sec.
Independently audio working fine.
After tracing we find that noise coming when rgb2yuv asm routine is getting called in video driver.
So we have commented the routine & tried by calling a rgb2yuv C function in the same driver file.
If our computation is as
y1 = r1 +g1+ b1;
cb = r1 -g1 +b1 ;
cr = r1 - g1 -b1;
we are not getting noise prob.
But if we changed our computation to
y1 = (299*r1 + 587*g1+ 114*b1)/1020;
cb = (-169*r1 - 331*g1 + 500*b1 + 128)/1020;
cr = (500*r1 - 419*g1 - 81*b1 + 128)/1020;
problem appears & frequency of noise is more..
Any help is highly appretiated...
thanks & regards
2008-03-25 23:29:13 Re: Click sound/noise while playing audio with jpeg
Mike Frysinger (UNITED STATES)
Message: 53024 seems fairly obvious ... multiplication/division operations are heavy expensive and will take up the core unlike addition/subtraction which are very few cycles
you should always avoid colorspace conversion. make all your software use the same colorspace as the actual hardware.