static void opt_format(const char *arg) { /* compatibility stuff for pgmyuv */ if (!strcmp(arg, "pgmyuv")) { opt_image_format(arg); arg = "image"; } file_iformat = av_find_input_format(arg); file_oformat = guess_format(arg, NULL, NULL); if (!file_iformat && !file_oformat) { fprintf(stderr, "Unknown input or output format: %s\n", arg); exit(1); } }