libpng delegate no longer found

[axelrose]

Hi all,

I try to compile 6.9.2-8 but can no longer bind the libpng delegate. "./configure --with-png=yes" ends up with the report

Code: Select all

  PNG               --with-png=yes              no

Up to 6.8.9-10 everything works well though. The same compiled libpng is recognized. I tried libpng 1.6.18, 1.6.19 and 1.6.20, just didn't dare to check 1.7beta yet.

The configure shell code from 6.8.9-10/configure and 6.9.2-8/configure looks very different when checking for the PNG delegate library.

So my question: did I miss some important change for using libpng or is it just a local incident.


Thanks for your time,
Axel.

[fmw42]

To help the developers, please specify what platform and how you installed IM (from binary or from source). Where did you get the installation module?

What do you get from

Code: Select all

convert -version

[axelrose]

I compiled from source using ImageMagick-6.9.2-8.tar.gz and libpng-1.6.19.tar.gz

roughly like this:

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mkdir /tmp/install
cd libpng-1.6.19
./configure CFLAGS=-O3 --prefix=/tmp/install --enable-shared --disable-dependency-tracking
make check && make install
cd ../ImageMagick-6.9.2-8
./configure LDFLAGS=-L/tmp/install/lib CFLAGS=-O3 --prefix=/tmp/install --enable-shared --disable-dependency-tracking --with-png=yes
make check

PNG is a usable delegate for me with this procedure and IM 6.8.* but not with 6.9

[fmw42]

What do you get from

Code: Select all

convert -version

What is your platform?

[axelrose]

MacOS X 10.11.2

I cannot build 6.9.2-8 so cannot report "convert -version"

My latest 6.8.9-10 build though gives:

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Version: ImageMagick 6.8.9-10 Q16 x86_64 2015-11-11 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2014 ImageMagick Studio LLC
Features: DPC OpenCL
Delegates: jng jpeg lcms png tiff webp xml zlib

[magick]

Modern releases of ImageMagick uses libpng.pc to find and configure the PNG delegate library. Make sure libpng.pc is in your configure path. You can set a custom path with the PKG_CONFIG_PATH environment variable. If that fails, review config.log. It will tell you exactly why the PNG delegate failed to validate.

[fmw42]

I am on Mac OSX snow leopard. I had to install pkgconfig and then set it s path in my .profile file.

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cat .profile

# MacPorts Installer addition on 2011-11-30_at_14:35:14: adding an appropriate PATH variable for use with MacPorts.
export PATH=/opt/local/bin:/opt/local/sbin:$PATH
# Finished adapting your PATH environment variable for use with MacPorts.

export PATH="${PATH}:/Users/fred/Applications/ImageMagick-Scripts/bin:/Users/fred/Applications/ImageMagick-Scripts/bin/Instagrams"
export DISPLAY=:0
export GDFONTPATH=/Library/fonts/
export TMPDIR=/tmp
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig:/opt/local/lib/pkgconfig

I use MacPorts to install most of my delegates (but not pkgconf) and then install IM from source. See viewtopic.php?f=1&t=21502&p=88202&hilit ... rts#p88202

But you could just install IM from binary or from MacPorts.

[axelrose]

Thank you very much for both valuable hints.

After having "pkg-config" installed in my $PATH the problem went away. libpng was found and PNG is now a valid delegate! :)

But I also had to set PKG_CONFIG_PATH to /tmp/install/lib/pkgconfig to avoid the use of a local and outdated /opt/X11/lib/libpng15
PKG_CONFIG_LIBDIR is even more rigorous and useful to me.


BTW
> review config.log. It will tell you exactly why the PNG delegate failed to validate.

This is what I am told:

configure:30964: checking for PNG
configure:31023: result: no
configure:31033: result:
configure:31281: result: -------------------------------------------------------------
configure:31283: checking for TIFF

So perhaps it would help others if the messages report a possibly missing "pkg-config" tool.


Cheers, Axel.

[uman]

Hi,

After having the same issue, I wanted to give out some feedback.

When running configure, we have under "some influential environment variable" quite a few of ***_LIBS and ***_CFLAGS (even ***_PKG), but looking at the configure.ac and configure file, it looks like you are ignoring those value by setting them to an empty string.

Either I'm using the tools in a wrong way, or you shouldn't list the ***_LIBS and ***_CFLAGS under the influential environment variable.