Color depth issues

[chainsawbeer]

While going through some photos it occured to me just now that the color depth seems skewed a bit. Its like looking at images on one of the old 4096 color devices. As far as I can tell there's nowhere inside of wm5 to change bit-depth on the display and the only thing I can guess is that one of the programs I installed recently may have tweaked a registry entry somewhere. Are rescoe photo viewer or conduit pocket artist known for this kind of behavior? Other than that a few games are the only other 3rd party apps I've installed.

[lbendlin]

The display on the Universal shows 16 bit (565) but the pictures themselves are 24 bit. If you look at them on a PC you will see the full quality.

[chainsawbeer]

I'd be willing to accept that explanation if it wasnt for the fact that not so long ago the image clarity was exceptional... the color depth and apparent dithering has gone from amazing to hardly tolerable. I was poking around inside morphgear and saw that it had driver changing options and that the configuration menu (graphics or otherwise) seemed to make the display go a bit wonky.

[chainsawbeer]

Hrmmm... attempted a hard reset and still no better. It did occur to me that I hadnt really done anything graphical until recently and not TOO long ago I had an LCD replacement done by pocketpctechs.com. Does anybody know if they use the OEM LCDs or if maybe I would have gotten an old 4096 color model?

[ZeBoxx]

You could try and check with the attached testpatterns.

They are basically three vertical gradients - greyscale, red, green, and blue
Each gradient in turn is composed of 3 columns
left column: 16bit - Rx5bits (32 levels) Gx6bits (64 levels) Bx5bits (32 levels)
middle column: 24bit - RGBx8bits (256 levels)
right column: 12bit - RGBx4bits (16 levels)

There's two files - one with dithering and one without (banding). The dithering method used is a basic Floyd-Steinberg which is used in most dithering engines next to a regular dither (not included, but I have one of those in the same kit

Be sure to view the image full-screen, as otherwise you will run into resizing issues :)

What you'll be looking for, essentially, is which of the two left/right columns most resembles the center column. Unless you have a full 24bit device, there should be either banding or dithering occuring, and the center column should look like the left or right column.

If you're not sure - load the image, take a screengrab ("Magic SS" functions with VGA), and attach the result here for us to peek at. I'm *assuming* that it would grab the actual output data and would thus get us the screengrab post-bitreduction :)

[chainsawbeer]

well, it would APPEAR that everything is in order, in the standard non-dithered image the left column matches up best visually to the center which would indicate a 16bit display, as the device is rated. however, in all my time of graphics work, downsampling a 24bit image to display on a 16bit display has never produced such unsightly results

[lbendlin]

magicss will force the saved BMP into 565 (16 bit). For a true 24 bit screen capture use my ScreenShotCE program (search Handango)

(of course this is a red herring since the screen is 16 bit, and not 18 or 24 bit.)

[ZeBoxx]

yeah, the point was to get a screengrab of what he's actually seeing - not what's being sent to the driver -before- downsampling/etc. :)

[amignec]

I have the some problem about.. the color deth is low, I have bad quality, it look like 4096 colors, the today screen, the pics, the movies.. everything, I tryed a hard resert, but nothing to do..

Some help ???


MDA II - WM5 2.01a