Images Miscolored

[Mark Smith]

Scott, I've just been fooling around with the images in your  
colorshift stack. I found that the photoshop image has a gamma- 
correction chunk, and that the value is different from the value  
returned by the screenGamma function in rev. On my machine (mac book  
pro), the default screenGamma value appears to be 1.7.

If I set the the screenGamma to the value found in the photoshop png, do
set the text of image "test1.png" to the text of image "test1.png",  
then the color changes to match the others....

So I've made a little stack that contains functions for getting the  
gamma correction value from a png image (one for images already  
imported, one for files on disc), and an example of using it.

I also made png images in Graphic Converter and Photoshop Elements  
with a solid color of 70,140,210 and imported them into rev. The  
color changed to 47,116,198 for GC and 65,135,208 for PE but there is  
no gamma correction chunk in the HC image, so I don't know how to  
deal with that.

I think what's happening is clearer in the stack.

It's on RevOnline

Category: Programming
Name: pngGamma

See what you think...

Best

Mark