Werner LEMBERG <w...@gnu.org> writes: >> I know from my Windows pixel-based checker that, generally, the PNG >> files contain the same image, version after version (there are a few >> oddities with some text, which I'm used to). I would have believed >> that identical images would only be produced by identical PNG files? > > Usually, picture container formats like PNG also contain metadata like > the date of image creation or a comment. This makes PNGs different > even in case the contained images are identical.
Also they are compressed, and even with lossless compression, there is more than one valid representation for most data. However, if there is no time stamp in the image data and the image is created by the same software, chances are that a byte-by-byte comparison will largely reduce the amount of data one has to compare more carefully. -- David Kastrup _______________________________________________ lilypond-devel mailing list lilypond-devel@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-devel
