ffmpeg (avcodeclib) & png support

I'm building ffmpeg libraries on Windows with a --enable-decoder=png switch. However开发者_如何转开发, after successful build, there is no png support. Any ideas what went wrong?

For me the issue was Zlib, FFmpeg will only include PNG support if Zlib is found

wget zlib.net/zlib-1.2.8.tar.xz
tar xf zlib-1.2.8.tar.xz
cd zlib-1.2.8
make -f win32/Makefile.gcc install \
  PREFIX=$HOST- \
  DESTDIR=$PREFIX \
  BINARY_PATH=/bin \
  INCLUDE_PATH=/include \
  LIBRARY_PATH=/lib

Example

I am assuming you are using Cygwin. Most probably you do not have libpng installed in your Cygwin installation. To install, you need to launch the "setup.exe", which is what you have used to install your Cygwin environment, and find "png" under the installation package. Update and you are ready to use png with your ffmpeg program.