Adds libpng to OSX contribs (for the logo filters)

extras/contrib/src/Makefile

@@ -55,7 +55,7 @@ all: .autoconf .libtool .automake .iconv .intl .pkgcfg .freetype .fribidi \
 	.a52 .mpeg2 .id3tag .mad .ogg .vorbis .vorbisenc .theora \
 	.FLAC .speex .faad .faac .lame .ebml .matroska .ffmpeg .openslp \
 	.dvdcss .dvdread .dvdnav .dvbpsi .live .goom .caca .mod \
-	.cddb .cdio .vcdimager
+	.cddb .cdio .vcdimager .png
 endif
 ifeq ($(SYS),BEOS)
 all: .perl .autoconf .libtool .automake .iconv .intl .freetype .fribidi \
@@ -950,6 +950,25 @@ CLEAN_FILE += .toolame
 CLEAN_PKG += toolame
 DISTCLEAN_PKG += toolame-$(TOOLAME_VERSION).tar.bz2
 
+# ***************************************************************************
+# libpng
+# ***************************************************************************
+
+libpng-$(PNG_VERSION).tar.bz2:
+	$(WGET) $(PNG_URL)
+
+libpng: libpng-$(PNG_VERSION).tar.bz2
+	$(EXTRACT_BZ2)
+	cat Patches/libpng.patch | sed s,PREFIX,$(PREFIX), | patch -p0
+
+.png: libpng
+	(cd $<; cp scripts/makefile.macosx Makefile && make shared && make install)
+	touch $@
+
+CLEAN_FILE += .png
+CLEAN_PKG += libpng
+DISCLEAN_PKG += libpng-$(PNG_VERSION).tar.bz2
+
 # ***************************************************************************
 # Some cleansing
 # ***************************************************************************

extras/contrib/src/Patches/libpng.patch

+--- libpng/scripts/makefile.macosx	Sun Sep 26 18:18:04 2004
++++ libpng/scripts/makefile.macosx.orig	Thu Oct  3 13:32:34 2002
+@@ -6,7 +6,7 @@
+ # For conditions of distribution and use, see copyright notice in png.h
+ 
+ # where make install puts libpng.a and png.h
+-prefix=/usr/local
++prefix=PREFIX
+
+ # Where the zlib library and include files are located
+ #ZLIBLIB=/usr/local/lib

extras/contrib/src/packages.mak

@@ -107,4 +107,5 @@ CDIO_VERSION=0.70
 CDIO_URL=$(GNU)/libcdio/libcdio-$(CDIO_VERSION).tar.gz
 TOOLAME_VERSION=02m-beta8
 TOOLAME_URL=$(VIDEOLAN)/testing/contrib/toolame-$(TOOLAME_VERSION).tar.bz2
-
+PNG_VERSION=1.2.5
+PNG_URL=$(VIDEOLAN)/testing/contrib/libpng-$(PNG_VERSION).tar.bz2