Re: PNG loading time

Hi Karl,

> BTW: the pdftex manual gives (thanks to Hans, I believe) two specific
> cases that disable copying: interlaced PNGs, and PNGs using gamma
> correction.

Yes, those are very common cases, indeed. The most common ones.

> I confess I did not delve into the details of the other cases you and
> Hartmut mentioned (cHRM, bKGD, "colortype 3 palettes"), but I mentioned
> them in the manual anyway, along with RGBA. --thanks, karl.

Not that it needs mentioning, but I wrote a tool that detects and
converts pngs to a fast copy mode:
	https://github.com/norbusan/png-pdftex-tool
Python, no external dependencies.

> pixel graphics (\eg\ line scans, screenshots). As of \PDFTEX\ 1.30.0,
> the alpha channel of \PNG\ images is processed if available; this allows

??? Is that true? The code in writepng.c does seem to remove the alpha
channel? RGBA will normally also result in reencoding.

Best regards

Norbert

--
DI Dr Norbert Preining                        https://www.preining.info
arXiv / Cornell University   +   IFMGA Guide   +   TU Wien  +  TeX Live
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