Re: libpng complexity (Was: [PNG] Cancel meeting?)

This is off topic but:

> FWIW – Adobe uses libpng for all of our desktop and mobile applications
(for the web we let the browser do the work for us).

At present yes; I just double checked and you write 1MByte IDAT chunks.  I
was thinking of PhotoShop before 2001; at that time I saw a number of
in-house generated images with a single IDAT exceeding 1MByte, but I
believe PhotoShop was using a plug-in to write PNG.  Making such images
with libpng is pretty much impossible; libpng pre-allocates a buffer for
the whole IDAT.   It's easy to use a second pass, "pngfix --max" will do
it, so maybe that is what was happening originally.

png-mng-implement is the right place for such discussions.  It's important
to know what APIs in libpng are really being used because any reduction on
the complexity and arcanity of the implementation is only likely to be
achieved without a radical rewrite (which I previously abandoned) by
eliminating APIs.