Changing Canvas Size resets color depth to 24bpp

[otiecoyote]

I've seen this happen in most of the versions if Irfanview I've used over the past couple of years. My use of the software is to convert images down to as much as a four-color greyscale image for IP telephone displays. After decreasing the color depth to a custom setting of 4 colors, then changing the canvas size (to center the image for the phone, usually a f1xed 114 x 51 screen), the color depth resets to 24bpp. If I dont catch this and set it back to 4 colors, the file becomes too large to load on my device.

I could change the order that I do this task, but I figured I'd let someone know what I've observed.
Thanks.

[Sam_Zen]

Welcome otiecoyote !

Good point. There are more functions in IV with this rather annoying habit of setting the color depth back to 24bpp..
I can imagine happening this when applying a 'Sharpen', but often it's done without any obvious reason.

Maybe the crux is the color management of each tool.
When using the Change canvas size, one can choose an additional color, but that is still from a full spectrum,
not from the actual palette of the file.