I wrote a test:

My PNG file in the test has a 256 colo=
ur palette:

nbullock/image-png-libpng/blob/master/t/tantei-san.png">https://github.com/=
benkasminbullock/image-png-libpng/blob/master/t/tantei-san.png
>

--000000000000e1ab0205b662fc04--


--===============5947092897941207110==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline


--===============5947092897941207110==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
png-mng-implement mailing list
png-mng-implement-at-lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/png-mng-implement

--===============5947092897941207110==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
Hangout mailing list
Hangout-at-nylxs.com
http://lists.mrbrklyn.com/mailman/listinfo/hangout

--===============5947092897941207110==--

--===============5947092897941207110==
Content-Type: multipart/alternative; boundary="000000000000e1ab0205b662fc04"

--000000000000e1ab0205b662fc04
Content-Type: text/plain; charset="UTF-8"

I've implemented this in my Perl module:

https://github.com/benkasminbullock/image-png-libpng/blob/master/tmpl/Libpng.xs.tmpl#L393

I wrote a test:

https://github.com/benkasminbullock/image-png-libpng/blob/master/t/get-palette-max.t

My PNG file in the test has a 256 colour palette:

https://github.com/benkasminbullock/image-png-libpng/blob/master/t/tantei-san.png

But the test outputs 0, rather than 256.

What does png_get_palette_max do? The documentation seems to imply it will
return the number of colours in the palette.

I googled for examples of this function but didn't find anything.

--000000000000e1ab0205b662fc04
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable