I am working on Image processing with deep learning and I came on to the topic Error level Analysis which gives/shows the difference in compression level(I'm trying to show if the image as gone under multiple compressions or not) in JPEG (lossy compression).
Are there any other techniques which are similar to ELA on JPEG and techniques similar or different which can be used on PNG as well to show multiple compressions?
There cannot be, IMHO.
Since PNG compression is lossless, every decompression must result in the identical original image. Therefore, every recompression will start from the same place so no history can be retained.