+CHECK_LIB([opus], [opus], [opus_multistream_decoder_create])
+CHECK_HEADERS([opus], [libopus headers], [opus/opus_multistream.h])
+CHECK_LIB([libaom], [aom], [aom_codec_version])
+CHECK_HEADERS([libaom], [libaom headers], [aom/aom.h])
+CHECK_LIB([dav1d], [dav1d], [dav1d_version])
+CHECK_HEADERS([dav1d], [libdav1d headers], [dav1d/dav1d.h])
+CHECK_LIB([libwebp], [webp], [WebPGetEncoderVersion])
+CHECK_HEADERS([libwebp], [libwebp headers], [webp/encode.h])