hello, I know this post might be a bit old, but Im having these issues as well at this current time.
I noticed that on the roblox web page, the images appear to be fixed, but they are still broken when viewing from the tool box in the studio:
not all images are like this so I assume it has to do with the image size like people have said above. I upload a lot of small images with the most recent being 32x32 pixels in size. the images are fine when I insert them into a game its only the preview that’s the issue.
Seems like the issue isn’t fixed yet. I uploaded some icons for a game and the previews for it is broken in the website and the Asset Manager. Even worse, some decals are showing previews of images I have never uploaded at all:
Just in case engineers are not aware, this is very likely an issue with uninitialized memory (i.e. from a bad pointer) being returned instead of the correct thumbnail result.
This is because the garbage you get is clearly wrongly decoded or offset PNG data (i.e. the diagonal striping effect), or sometimes other peoples’ thumbnails that have been partially overwritten with other memory (i.e. damaged with noise).
This only happens to greyscale images with transparency.
About:
I released an update to my game a month ago and used a different endpoint so then I could grab an automatically compressed image at lower resolutions (I like to just upload 420x420 - 1024x1024 and let Roblox automatically give me lower endpoints as I need them) to greatly reduce client memory for several of my game asset icons. While most of them were fine, usually the older ones, there were a few of them that appeared ‘distorted’.
The decal ids work on C and D in-game but appear corrupted, while the image ids of both C and D seem to not be the correct ones. Even if I’m supposed to use the decal id and not the image id for these endpoints, it still does appear corrupted so I am unable to use them regardless.
I have the same problem. I uploaded an arrow icon today, and it looks corrupted.
In the Asset Manager:
In Game:
It also looks this way on the Create page, but strangely, all of the images on the Decals page are corrupted but only some of them are on the Images page.
I had this happen to me too at one point, but it only happened for one decal specifically in a bundle of decals I uploaded. Very bizarre bug, but I didn’t know it was just the preview so that’s good to know.
Hey developers, apologies for the delay!
This issue is still under investigation but in the meantime - engineers recommend to not use 8 bit grayscale PNGs while we work on a fix.
I understand the reasoning behind the avoiding, but this is a band-aid fix and does not resolve the issue the way I would have hoped; there are certain images that I cannot upload in any other format other than 8 bit grayscale PNGs. Is there a timeframe for when this may get fixed. This issue actually got me a warning and I had to re-upload a decal a couple of times before it would get approve because it appears the moderators were seeing this:
Moderators review the source asset, not the thumbnail. The warning was likely inaccurate and related to the fact the image is all white and distorted text, they have historically had problems with the moderation accuracy there.
I expect mixed channels problem to be fixed now. It took place for grayscale with transparency images, but approximately 2 weeks ago it should go away (for newly generated thumbnails). Please, verify that the problem is solved or tell me if it persists.
What I see as the thumbnail:
This isn’t a distorted grey image but rather a contrast change it seems.
Of course this just affects the preview only, not the actual decal itself. But just a reminder I currently experience this issue. This issue did not occur in January but seems to reoccur now.
Quick edit: The distorted grey preview still occurs, seems either your preview image gets a contrast change or a grey distortion
We have one more channel mix-up problem when creating jpeg thumbnails for 2 channel (grey and alpha) png decals. It definitely should be fixed.
The other one is a little bit more controversial. In your image grey channel is set to 0 everywhere and the outline is created with alpha. Since jpegs cannot have alpha we are throwing it away effectively suggesting the background to be black. This way if I just fix the first problem, your thumbnail will get worse actually, it will become all black. I performed a quick research and found out that there is no general consensus on what background should be used when converting images with alpha to alpha-less ones. But it seems there is some bias for using white background. It will be good for your case also. I need to research more how it will affect other user’s content and discuss with colleagues how to do better.
Two issues were observed to affect this feature. First is a color channel mix up which has now been resolved. The second is part of the problem is still being worked on.
