$ ls -l /usr/include/*png* /usr/lib/*png*
lrwxrwxrwx 1 root root   18 Dez 18 10:43 /usr/include/pngconf.h -> libpng15/pngconf.h
lrwxrwxrwx 1 root root   14 Dez 18 10:43 /usr/include/png.h -> libpng15/png.h
lrwxrwxrwx 1 root root   21 Dez 18 10:43 /usr/include/pnglibconf.h -> libpng15/pnglibconf.h
-rwxr-xr-x 1 root root 155K Dez 17 12:15 /usr/lib/libpng12.so.0*
-rw-r--r-- 1 root root 275K Dez 18 10:43 /usr/lib/libpng15.a
lrwxrwxrwx 1 root root   19 Dez 18 10:43 /usr/lib/libpng15.so -> libpng15.so.15.17.0*
lrwxrwxrwx 1 root root   19 Dez 18 10:43 /usr/lib/libpng15.so.15 -> libpng15.so.15.17.0*
-rwxr-xr-x 1 root root 186K Apr 24  2013 /usr/lib/libpng15.so.15.15.0*
-rwxr-xr-x 1 root root 183K Dez 18 10:43 /usr/lib/libpng15.so.15.17.0*
lrwxrwxrwx 1 root root   10 Dez 18 10:43 /usr/lib/libpng.a -> libpng15.a
lrwxrwxrwx 1 root root   11 Dez 18 10:43 /usr/lib/libpng.so -> libpng15.so*

/usr/include/libpng15:
total 152K
-rw-r--r-- 1 root root  21K Dez 18 10:43 pngconf.h
-rw-r--r-- 1 root root 120K Dez 18 10:43 png.h
-rw-r--r-- 1 root root 6,2K Dez 18 10:43 pnglibconf.h