Trouble with image colors

[Carolyn]

Hi,

My images also seem washed out on a specific computer we are running our study on. I double checked by opening the actual BMP file (saved from PPT) and there the images look perfect. As soon as I run the file in DirectRT the images look washed out/over exposed (e.g., too bright). I checked my screen resolution settings and the DirectRT style settings and everything seems fine.

I would appreciate any extra suggestions you may have.

[jarvis24]

Can you send me one of these images and a copy of your style (.drt) file?

[solomon]

hi

I am having a similar problem. My bmp images are orginally black and white, and when viewed in image viewing or editing software (e.g. photoshop, paint, ifranview) they appear fine. However, when I attempt to display them in DirectRT, they appear blotchy in some parts of the image, and other colours (e.g. red and green) become visible. I have tried various monitor resolutions and resizing the images, but no success. Attached is one of the files.

[jarvis24]

Can you post or send me a copy of the style (.drt) file and input file you are using and also a copy of your system diagnostics via dxdiag? Instructuctions for the latter are here: www.empirisoft.com/Support/showthread.php?t=75

Will take a look and see if I can tell what's up with it.

-Blair

[solomon]

Thanks for your time. Here are the attached files.

[jarvis24]

Your dxdiag file looks fine although the driver for your video card is pretty old (2000) you may want to try an update if you can find one.

Some questions..

Does the same effect occur for any of the DirectRT samples that use images, e.g.,

C:\DirectRT\Samples\4 applications\image priming\implicit.csv

If it's unique to this study you are running, I'd be curious to know if the images from the sample above look washed out when used in your study. Or, if the images in your study look washed out when used in that sample.

[jarvis24]

I looked at your files again. You are using 24-bit images with many shades of grey against a grey background. I'm assuming you want the image to blend into the background. DirectRT uses 16-bit colour by default--the impact this has on images is usually minimal and is worth the savings in processing load.

In some cases though, 16-bit colour can adversely affect image quality. When this happens (as it also does with videos/movies on occasion), you can tell DirectRT to use 24-bit colour by placing a simple text file with the number "24" in it in your experiment folder. Call the file "colour.txt". I've attached a sample of such a file. Doing this will preserve 100% of the quality of your 24-bit images. Note that "32" will also work if your system prefers that.

Note that another strategy would be to reduce the number of colours in your images to 256. Irfanview has a function for this and does a nice job (see Image > Reduce Color Depth).

Finally, if you want your picture to blend in perfectly with the background, you might create a background image of the colour you want and display the subsequent picture over top of that so the match is exact. Some systems vary in how they display colours as set in the style file.

The super perfect fix for your study, I expect, will be to keep your images as is and use the 24-bit (or 32-bit) colour.txt function in combination with a background which is a full screen grey image.

Hope that helps,
-Blair