On 8/30/06, <b class="gmail_sendername">Yves Degoyon</b> <<a href="mailto:ydegoyon@free.fr">ydegoyon@free.fr</a>> wrote:<div><span class="gmail_quote"></span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
ola,<br><br>><br>><br>> i would also be interested in which context "RGBA" is twice as heavy<br>> as "YUV" (with respect to Gem/pdp)<br>><br>it's as simple as have shown dumb+dumber :<br>
<br>in RGBA format, a pixel is represented by 4x(data size)<br>in YUV planar 4:2:2 format, it is represented by :<br> 1Y + 1/4*U +1/4*V = 1,5*(data size )</blockquote><div><br>Technically that is 4:2:0. ;)<br><br>4:2:2 would be represent as 1Y + 1/2U + 1/2V in your notation. That is 16 bits per pixel or two in the 32bit space required for RGBA.
<br></div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">of course, loops are much faster with YUV 4:2:2</blockquote><div><br>Just about everything related to video is faster with YUV processing. That's why both PDP and GEM have full YUV chains right?
<br></div><br>cgc<br></div><br>