02-19-2013, 01:58 PM
(02-19-2013, 12:23 PM)Davy Jones Wrote: How does this exactly work?
The PNG file format is horrifically complicated... PNG files use compression, but it depends on how you create the data blocks and chunks to get an optimal size. I don't know how exactly things work, but some PNG libs do their optimization job better than others.
The darkening isn't a result of the optimization and compression, but some other flaws somewhere else in some PNG processing utilities (it may result from pixel format conversions for example).