Generating HDMI 1.4 compliant 3D images?

Jonathan Morton jonathan.morton at movial.com
Thu Jul 15 01:46:36 PDT 2010


On Thu, 2010-07-15 at 10:35 +0200, Florian Echtler wrote:
> There's 45 black lines of blanking space in between the two images.
> WTH? This is a digital format, right?

So is DVI, which HDMI is based on.  Still has both horizontal and
vertical blanking intervals, which need to be specially reduced from CRT
values to keep the dotclock within sane limits.

My guess is that it's a hack-format, which actually does Alternate Frame
Rendering.  The blanking lines are to minimise the intelligence the CRTC
needs, at the expense of 90 kilopixels of wasted VRAM.  Beautiful, huh?

IMHO it's in the same league as YCbCr, which uses the 16-240 value range
on the wire (and within DVD codecs), just because the analogue signal it
replaces did something equivalent for entirely reasonable analogue
reasons.  The TV expands it on receive, so that 16 is black and 240 is
white.

-- 
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From: Jonathan Morton
      jonathan.morton at movial.com




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