Install libimagequant for Travis build

.travis.yml

@@ -45,6 +45,9 @@ install:
   # openjpeg
   - pushd depends && ./install_openjpeg.sh && popd
 
+  # libimagequant
+  - pushd depends && ./install_imagequant.sh && popd
+
 script:
   - if [ "$TRAVIS_PYTHON_VERSION" != "nightly" ]; then coverage erase; fi
   - python setup.py clean

depends/README.rst

@@ -1,8 +1,8 @@
 Depends
 =======
 
-``install_openjpeg.sh`` and ``install_webp.sh`` can be used to
-download, build & install non-packaged dependencies; useful for
+``install_openjpeg.sh``, ``install_webp.sh`` and ``install_imagequant.sh`` can
+be used to download, build & install non-packaged dependencies; useful for
 testing with Travis CI.
 
 The other scripts can be used to install all of the dependencies for

depends/debian_8.2.sh

@@ -14,3 +14,4 @@ sudo apt-get -y install libtiff5-dev libjpeg62-turbo-dev zlib1g-dev \
      python-tk python3-tk
 
 ./install_openjpeg.sh
+./install_imagequant.sh

depends/install_imagequant.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+# install libimagequant
+
+git clone https://github.com/pornel/pngquant
+
+pushd pngquant
+
+make -C lib shared
+sudo cp lib/libimagequant.so* /usr/lib/
+sudo cp lib/libimagequant.h /usr/include/
+
+popd

depends/ubuntu_12.04.sh

@@ -14,3 +14,4 @@ sudo apt-get install libtiff4-dev libjpeg8-dev zlib1g-dev \
 
 ./install_openjpeg.sh
 ./install_webp.sh
+./install_imagequant.sh

depends/ubuntu_14.04.sh

@@ -12,3 +12,4 @@ sudo apt-get -y install libtiff5-dev libjpeg8-dev zlib1g-dev \
     python-tk python3-tk
 
 ./install_openjpeg.sh
+./install_imagequant.sh