Sunday, July 18, 2010

Massive increase in picture quality

I've always been a bit dissatisfied with the quality of the video that came from the HTPC - for some reason, I could never get the blacks really black. Its as if the gamma setting was still turned up. I've spent a couple of hours over the last few months playing with brightness, etc - trying to get it right.

Even when using the calibration videos in Media Center, I could get the pic to about 8/10 - not the expected 10/10 that I was aiming for (remember... no compromises!).

I played around some more with the graphic card driver and discovered a setting to change the pixel type from YCBCr to RGB. The jump in picture quality is incredible.

I did some research into why - and discovered this pretty technical link

Now, I don't profess to really understand much of this... but I do know that now I can get the "blacker than black", which seems to be 0 on a scale of 0 - 255... whereas before, it seems the lowest I could get was 16 out of 255.

So I'm pretty pleased with the picture now... it equals the picture coming from the tuner.

And another discovery. If you're in Australia, you'll know that 7 and 9 have a High Definition version of the standard definition channels. Picture quality wise - they are pretty much identical.

In the morning, I usually watch the Sunrise morning program while getting ready for work. The text down the bottom of the screen always had blotchy stains underneath the rendering:

The HD versions of the channels, in conjunction with the RGB, rather than YCbCr - completely eliminates these blotches and ghosts. I don't know why SD has them... its rather like analogue ghosting... which just shouldnt happen in digital.

anyway... they're gone now. Reprogrammed the "7" channel to point to 70 (7 HD)  and the "9" to point to 90. Cool.

No comments:

Post a Comment