av_guess_image2_codec  746 libavformat/avformat.h enum CodecID av_guess_image2_codec(const char *filename);
av_guess_image2_codec  184 libavformat/utils.c         av_guess_image2_codec(filename) != CODEC_ID_NONE) {
av_guess_image2_codec  237 libavformat/utils.c             codec_id= av_guess_image2_codec(filename);