I've been trying to upload a personal favorite piece that used to be on the hub from SingleSalt now that they're allowed again, but I keep getting an error message telling me that this piece already exists - even though it was deleted long ago.

Any advice on how I can upload it? Or a way to get the post back?

what you need to do is edit one pixel on it then try uploading again. that should make it work.

That. Small problem:If it's a jpg/jpeg, editing it in any way then saving it in the same format will cause the quality to drop. It's impossible to change jpegs without the new image being lossily compressed again, even if you set the quality to maximum. A couple iterations of that can turn any picture into an artifact-ridden mess.

You might want to save the changed version as png. It will be bigger, but the quality won't suffer.

Alternatively, you can add a character at the end of an image file. In jpg, png, and gif, there is a file-end marker and any characters after it should get ignored so the image wouldn't change, but will still change the hash.