+ if( ac < 3 ) {
+ printf("usage: %s a.fmt b.fmt <frm0> <s>\n"
+ " a = src media, b = src media, frm0 = a/b skew\n"
+ " s = shift <0:lt, =0:none(dft), >0:rt\n"
+ " env var GG_LOG_LEVEL=q/f/e/v/d/<nbr>\n", av[0]);
+ exit(1);
+ }
+ const char *cp = getenv("GG_LOG_LEVEL");
+ if( cp ) {
+ int lvl = -1;
+ switch( *cp ) {
+ case 'q': lvl = AV_LOG_QUIET; break;
+ case 'f': lvl = AV_LOG_FATAL; break;
+ case 'e': lvl = AV_LOG_ERROR; break;
+ case 'v': lvl = AV_LOG_VERBOSE; break;
+ case 'd': lvl = AV_LOG_DEBUG; break;
+ case '0'...'9': lvl = atoi(cp); break;
+ }
+ if( lvl >= 0 )
+ av_log_set_level(lvl);
+ }