Transparent border appears when I use Image Size to shrink an image (bug)

In CS2 (9.0.2) and CS3 (10.0.1), whenever I shrink an image using Image Size, my layers get a slightly transparent edge. As a game developer, I make tiling textures a lot, and this generally ruins their tiling-ness.

Try this:
- create a 32x32 image, make it white
- add a layer, fill it with black
- shrink it to 16x16 or 20x20, using any of the Bicubic resampling methods - notice that the edge pixels of the black layer are slightly transparent. This is most noticeable in the corners of the image.

Is there a better place for me to report this bug? I haven't found one.

It's not a bug, but just an odd behavior. Believe it or not, for whatever reason, it's supposed to work that way. Don't get me wrong, though, we can agree that for an image like you've detailed in your example, this shouldn't happen.

Use Nearest Neighbor instead of Bicubic and you'll see that the edges and corners remain at 0, 0, 0.

Haha, you mean it's a bug in the spec rather than a bug in the implementation? (Unless there is actually a reason someone would want it to work that way.)

Yeah Bilinear and Nearest Neighbor both avoid the problem, but of course the image doesn't look as good.

I work around it by duplicating all my layers before shrinking. The problem is obvious (in-game) with only one layer, but still subtle enough that it's usually invisible after duplicating. Annoying, but it works.

Does your workflow allow you to flatten your image before down-sampling?

Right now that's a little more painful than duplicating the important layers. Good point though - I think that if I can change the script I'm using to export textures for the game so it flattens before resizing I'll be happy :)

Hope that change can work for you.