Run ffmpeg without outputting configuration information?
This is now possible as of FFmpeg 2.2 with the -hide_banner option. See also the relevant commit and ticket.
AFAIK there is no way, loglevel is no use. Look at ffmpeg.c:
init_opts();show_banner();and cmdutils.c:
void show_banner(void){ fprintf(stderr, "%s version " FFMPEG_VERSION ", Copyright (c) %d-%d the FFmpeg developers\n", program_name, program_birth_year, this_year); fprintf(stderr, " built on %s %s with %s %s\n", __DATE__, __TIME__, CC_TYPE, CC_VERSION); fprintf(stderr, " configuration: " FFMPEG_CONFIGURATION "\n"); print_all_libs_info(stderr, INDENT|SHOW_CONFIG); print_all_libs_info(stderr, INDENT|SHOW_VERSION);}See here for an unsuccessful attempt of skipping it (I don't get what the GPL has to do with anything of this). I suggest you to file a bug and hope you are convicing enough.
As many others, I have ffmpeg compiled with show_banner() commented out, it's simply tiresome.
Take a look at ffmpeg's manpage, especially the -loglevel parameter.