ffmpeg.c

    /* video options */
    { "b", HAS_ARG, {(void*)opt_video_bitrate}, "set video bitrate (in kbit/s)", "bitrate" },
    { "r", HAS_ARG, {(void*)opt_frame_rate}, "set frame rate (in Hz)", "rate" },
    { "s", HAS_ARG, {(void*)opt_frame_size}, "set frame size (WxH or abbreviation)", "size" },
    { "g", HAS_ARG | OPT_EXPERT, {(void*)opt_gop_size}, "set the group of picture size", "gop_size" },
    { "intra", OPT_BOOL | OPT_EXPERT, {(void*)&intra_only}, "use only intra frames"},
    { "vn", OPT_BOOL, {(void*)&video_disable}, "disable video" },
    { "qscale", HAS_ARG | OPT_EXPERT, {(void*)opt_qscale}, "use fixed video quantiser scale (VBR)", "q" },
    { "qmin", HAS_ARG | OPT_EXPERT, {(void*)opt_qmin}, "min video quantiser scale (VBR)", "q" },
    { "qmax", HAS_ARG | OPT_EXPERT, {(void*)opt_qmax}, "max video quantiser scale (VBR)", "q" },
    { "qdiff", HAS_ARG | OPT_EXPERT, {(void*)opt_qdiff}, "max difference between the quantiser scale (VBR)", "q" },
    { "qblur", HAS_ARG | OPT_EXPERT, {(void*)opt_qblur}, "video quantiser scale blur (VBR)", "blur" },
    { "qcomp", HAS_ARG | OPT_EXPERT, {(void*)opt_qcomp}, "video quantiser scale compression (VBR)", "compression" },
    { "bt", HAS_ARG, {(void*)opt_video_bitrate_tolerance}, "set video bitrate tolerance (in kbit/s)", "tolerance" },
#ifdef CONFIG_GRAB
    { "vd", HAS_ARG | OPT_EXPERT, {(void*)opt_video_device}, "set video device", "device" },
#endif
    { "vcodec", HAS_ARG | OPT_EXPERT, {(void*)opt_video_codec}, "force video codec", "codec" },
    { "me", HAS_ARG | OPT_EXPERT, {(void*)opt_motion_estimation}, "set motion estimation method", 
      "method" },
    { "sameq", OPT_BOOL, {(void*)&same_quality}, 
      "use same video quality as source (implies VBR)" },
    /* audio options */
    { "ab", HAS_ARG, {(void*)opt_audio_bitrate}, "set audio bitrate (in kbit/s)", "bitrate", },
    { "ar", HAS_ARG, {(void*)opt_audio_rate}, "set audio sampling rate (in Hz)", "rate" },
    { "ac", HAS_ARG, {(void*)opt_audio_channels}, "set number of audio channels", "channels" },
    { "an", OPT_BOOL, {(void*)&audio_disable}, "disable audio" },
#ifdef CONFIG_GRAB
    { "ad", HAS_ARG | OPT_EXPERT, {(void*)opt_audio_device}, "set audio device", "device" },
#endif
    { "acodec", HAS_ARG | OPT_EXPERT, {(void*)opt_audio_codec}, "force audio codec", "codec" },
    { "deinterlace", OPT_BOOL | OPT_EXPERT, {(void*)&do_deinterlace}, 
      "deinterlace pictures" },
    { "benchmark", OPT_BOOL | OPT_EXPERT, {(void*)&do_benchmark}, 
      "add timings for benchmarking" },
    { "hex", OPT_BOOL | OPT_EXPERT, {(void*)&do_hex_dump}, 
      "dump each input packet" },
    { "psnr", OPT_BOOL | OPT_EXPERT, {(void*)&do_psnr}, "calculate PSNR of compressed frames" }, 

    { NULL, },
};

int main(int argc, char **argv)
{
    int optindex, i;
    const char *opt, *arg;
    const OptionDef *po;
    INT64 ti;
    
    register_all();

    /* detect if invoked as player */
    i = strlen(argv[0]);
    if (i >= 6 && !strcmp(argv[0] + i - 6, "ffplay"))
        do_play = 1;

    if (argc <= 1)
        show_help();
    
    /* parse options */
    optindex = 1;
    while (optindex < argc) {
        opt = argv[optindex++];
        
        if (opt[0] == '-' && opt[1] != '\0') {
            po = options;
            while (po->name != NULL) {
                if (!strcmp(opt + 1, po->name))
                    break;
                po++;
            }
            if (!po->name) {
                fprintf(stderr, "%s: unrecognized option '%s'\n", argv[0], opt);
                exit(1);
            }
            arg = NULL;
            if (po->flags & HAS_ARG)
                arg = argv[optindex++];
            if (po->flags & OPT_STRING) {
                char *str;
                str = strdup(arg);
                *po->u.str_arg = str;
            } else if (po->flags & OPT_BOOL) {
                *po->u.int_arg = 1;
            } else {
                po->u.func_arg(arg);
            }
        } else {
            if (!do_play) {
                opt_output_file(opt);
            } else {
                opt_input_file(opt);
            }
        }
    }


    if (!do_play) {
        /* file converter / grab */
        if (nb_output_files <= 0) {
            fprintf(stderr, "Must supply at least one output file\n");
            exit(1);
        }
        
        if (nb_input_files == 0) {
            prepare_grab();
        }
    } else {
        /* player */
        if (nb_input_files <= 0) {
            fprintf(stderr, "Must supply at least one input file\n");
            exit(1);
        }
        prepare_play();
    }

    ti = getutime();
    av_encode(output_files, nb_output_files, input_files, nb_input_files, 
              stream_maps, nb_stream_maps);
    ti = getutime() - ti;
    if (do_benchmark) {
        printf("bench: utime=%0.3fs\n", ti / 1000000.0);
    }

    /* close files */
    for(i=0;i<nb_output_files;i++) {
        if (!(output_files[i]->format->flags & AVFMT_NOFILE)) 
            url_fclose(&output_files[i]->pb);
    }
    for(i=0;i<nb_input_files;i++) {
        if (!(input_files[i]->format->flags & AVFMT_NOFILE)) 
            url_fclose(&input_files[i]->pb);
    }

    return 0;
}