Need help with CVT timing on HDMI and bypassing HDTV image processing

Kiff Kannigan

Estimable
Jan 29, 2015
5
0
4,510
Hi! I have run into a somewhat peculiar issue with my TV which requires some explanation, so please bear with me! I've run into a brick wall here and I need some insight.

I bought this Thomson 55FU4243 HDTV for cheap some time ago - and while it's mostly been a nicely performing 1080p TV, I've always thought that it had some serious trouble correctly displaying warm colors in the red/yellow spectrum (faces look like flat, red blobs. Yuck).

Recently, however, I accidentally realized that connecting it to my PC at a resolution of 1366x768 somehow bypassed the entire image processing of the TV. I could no longer adjust sharpness or saturation, but the picture was drastically improved. Finally normally colored faces! So what do? The scientific approach!

I started diving into custom resolutions to see where the image processing is triggered. Turns out that any single pixel above 1366x768 activates image processing and ruins the picture. So I opened the advanced settings for my nVidia drivers and started toying around with different timings. Turns out that running a 1920x1080 60hz resolution triggers image processing on every timing preset except CVT (not reduced blanking).

So in short, 1920x1080 60hz with CVT-timing gives me an excellent picture that far surpasses the TV's default mode simply because it somehow makes the TV bypass its internal image processing. Great news for my PC content - but not so much for everything else I use the TV for, like all of my gaming consoles.

So my question is as follows: Any ideas on how I can convert a normal 1080p HDMI signal from any source into a 1920x1080 60hz signal specifically with CVT timing? I'm willing to try almost anything that doesn't require me to buy an entirely new TV.

EDIT: Adding some pictures to show you the difference I'm talking about.

This is a regular 1080p signal over HDMI from my computer:
rnUmgr5.jpg


And this is over HDMI from my computer, but with forced CVT timing:
kVzq5uW.jpg

I'd say that's a pretty drastic improvement - I just need help getting that quality across all my HDMI devices, not solely from my computer!
 

Kiff Kannigan

Estimable
Jan 29, 2015
5
0
4,510


Even if I convert the signal to composite, my TV will sadly still apply the same awful image processing to the signal (or at least, it does with the Nintendo Wii I've hooked up to that input). I am guessing this has to happen from HDMI to HDMI through a converter of some kind. If my computer is able to do this I'd be willing to try, but I don't know how that would work.

Another thing: The image processing doesn't apply at all to the VGA input, but converting HDMI to VGA made the picture all smudgy and awful - even if the colors were correct. Also, the sound and picture had a tendency to blink in and out of existence, so I scrapped that idea.
 

Kiff Kannigan

Estimable
Jan 29, 2015
5
0
4,510


I would settle for that if any of my HD consoles (PS3, PS4, Xbox 360) or my PVR decoder supported VGA - but I have to make this work with HDMI. I can change the HDMI timing to CVT if the signal comes from a computer, but none of the consoles are advanced enough to do the same - which is what the problem boils down to.
 

Kiff Kannigan

Estimable
Jan 29, 2015
5
0
4,510


I posted some pictures in my original post to illustrate the problem more specifically. Connecting any HDMI source to the TV enables some awful image processing to the picture which cannot be turned off. It makes the picture too red, oversharpened and unpleasant - and the TV's firmware does not support manual color calibration to rectify the worst of it.

Forcing the signal to run with CVT timing from a computer somehow bypasses that awful image processing, immensely improving the picture. I'm seeking a solution to do the same with all the boxes I've connected with HDMI - not just my computer.
 

Kiff Kannigan

Estimable
Jan 29, 2015
5
0
4,510
Bumping this with a more specific question which might help me resolve this:

Will an EDID flash or emulator help me get a signal with different timings? Let's say I set my desired resolution and timings as the "native" resolution in the EDID - will this be supported by PCs and gaming consoles? Also: can it control the color balance of the picture?