PNG End Bytes Significance?

[AceInfinity]

200 bytes is not bragworthy at all...
slowly getting better

So if you had a file of 1kb, and you could only remove 500 bytes from it, that would be unimpressive just because it's a small amount?

PNG is already a very minimal file format, basically compressed to it's max from the time it's been written into a byte stream to disk. There's not much other than arbitrary data that can be removed, and even at the most that can only be about 300-400 bytes sometimes. Compare the filesize between gif, png, and jpeg and you'll see what I mean about filesize. PNG is usually a smaller file format (and there's a reason for that), along with gif, especially in comparison to jpeg, but PNG supports a better tolerance for transparency (which occupies 1 byte in the PNG file - JUST for transparency) than gif, and jpeg doesn't support transparency at all, yet jpeg can be about 5 times that of a PNG equivilant if you were to convert from jpeg over to PNG structure.

JPEG has SO much useless data, at a lossless and careless level that I would pretty much never even consider using it as a fileformat unless it's absolutely required. PNG basically has a PNG signature, the PNG header (IHDR), arbitrary data, IDAT chunks (the actual image data without formatting) and the end of the byte stream constant called IEND.

It's not much more than that, and there's not much you can do with the IDAT chunks. Before that and after the header is almost all that you can modify in reality without loosing quality, until you get into changing the transparency ore removing that. But it's only a difference of 1 byte, so I don't think it's necessary. If you want a transparent PNG at least you know you're not packing on a lot of bytes.