avconv.c

        opt_audio_codec(o, "c:a", "ac3");
        parse_option(o, "f", "dvd", options);

        parse_option(o, "s", norm == PAL ? "720x576" : "720x480", options);
        parse_option(o, "r", frame_rates[norm], options);
        opt_default("g", norm == PAL ? "15" : "18");

        opt_default("b", "6000000");
        opt_default("maxrate", "9000000");
        opt_default("minrate", "0"); //1500000;
        opt_default("bufsize", "1835008"); //224*1024*8;

        opt_default("packetsize", "2048");  // from www.mpucoder.com: DVD sectors contain 2048 bytes of data, this is also the size of one pack.
        opt_default("muxrate", "10080000"); // from mplex project: data_rate = 1260000. mux_rate = data_rate * 8

        opt_default("b:a", "448000");
        parse_option(o, "ar", "48000", options);

    } else if(!strncmp(arg, "dv", 2)) {

        parse_option(o, "f", "dv", options);

        parse_option(o, "s", norm == PAL ? "720x576" : "720x480", options);
        parse_option(o, "pix_fmt", !strncmp(arg, "dv50", 4) ? "yuv422p" :
                          norm == PAL ? "yuv420p" : "yuv411p", options);
        parse_option(o, "r", frame_rates[norm], options);

        parse_option(o, "ar", "48000", options);
        parse_option(o, "ac", "2", options);

    } else {
        av_log(NULL, AV_LOG_ERROR, "Unknown target: %s\n", arg);
        return AVERROR(EINVAL);
    }
    return 0;
}

static int opt_vstats_file(const char *opt, const char *arg)
{
    av_free (vstats_filename);
    vstats_filename=av_strdup (arg);
    return 0;
}

static int opt_vstats(const char *opt, const char *arg)
{
    char filename[40];
    time_t today2 = time(NULL);
    struct tm *today = localtime(&today2);

    snprintf(filename, sizeof(filename), "vstats_%02d%02d%02d.log", today->tm_hour, today->tm_min,
             today->tm_sec);
    return opt_vstats_file(opt, filename);
}

static int opt_video_frames(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "frames:v", arg, options);
}

static int opt_audio_frames(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "frames:a", arg, options);
}

static int opt_data_frames(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "frames:d", arg, options);
}

static int opt_video_tag(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "tag:v", arg, options);
}

static int opt_audio_tag(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "tag:a", arg, options);
}

static int opt_subtitle_tag(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "tag:s", arg, options);
}

static int opt_video_filters(OptionsContext *o, const char *opt, const char *arg)
{
    return parse_option(o, "filter:v", arg, options);
}

#define OFFSET(x) offsetof(OptionsContext, x)
static const OptionDef options[] = {
    /* main options */
#include "cmdutils_common_opts.h"
    { "f", HAS_ARG | OPT_STRING | OPT_OFFSET, {.off = OFFSET(format)}, "force format", "fmt" },
    { "i", HAS_ARG | OPT_FUNC2, {(void*)opt_input_file}, "input file name", "filename" },
    { "y", OPT_BOOL, {(void*)&file_overwrite}, "overwrite output files" },
    { "c", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(codec_names)}, "codec name", "codec" },
    { "codec", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(codec_names)}, "codec name", "codec" },
    { "pre", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(presets)}, "preset name", "preset" },
    { "map", HAS_ARG | OPT_EXPERT | OPT_FUNC2, {(void*)opt_map}, "set input stream mapping", "file.stream[:syncfile.syncstream]" },
    { "map_metadata", HAS_ARG | OPT_EXPERT | OPT_FUNC2, {(void*)opt_map_metadata}, "set metadata information of outfile from infile",
      "outfile[,metadata]:infile[,metadata]" },
    { "map_chapters",  OPT_INT | HAS_ARG | OPT_EXPERT | OPT_OFFSET, {.off = OFFSET(chapters_input_file)},  "set chapters mapping", "input_file_index" },
    { "t", HAS_ARG | OPT_TIME | OPT_OFFSET, {.off = OFFSET(recording_time)}, "record or transcode \"duration\" seconds of audio/video", "duration" },
    { "fs", HAS_ARG | OPT_INT64 | OPT_OFFSET, {.off = OFFSET(limit_filesize)}, "set the limit file size in bytes", "limit_size" }, //
    { "ss", HAS_ARG | OPT_TIME | OPT_OFFSET, {.off = OFFSET(start_time)}, "set the start time offset", "time_off" },
    { "itsoffset", HAS_ARG | OPT_TIME | OPT_OFFSET, {.off = OFFSET(input_ts_offset)}, "set the input ts offset", "time_off" },
    { "itsscale", HAS_ARG | OPT_DOUBLE | OPT_SPEC, {.off = OFFSET(ts_scale)}, "set the input ts scale", "scale" },
    { "metadata", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(metadata)}, "add metadata", "string=string" },
    { "dframes", HAS_ARG | OPT_FUNC2, {(void*)opt_data_frames}, "set the number of data frames to record", "number" },
    { "benchmark", OPT_BOOL | OPT_EXPERT, {(void*)&do_benchmark},
      "add timings for benchmarking" },
    { "timelimit", HAS_ARG, {(void*)opt_timelimit}, "set max runtime in seconds", "limit" },
    { "dump", OPT_BOOL | OPT_EXPERT, {(void*)&do_pkt_dump},
      "dump each input packet" },
    { "hex", OPT_BOOL | OPT_EXPERT, {(void*)&do_hex_dump},
      "when dumping packets, also dump the payload" },
    { "re", OPT_BOOL | OPT_EXPERT | OPT_OFFSET, {.off = OFFSET(rate_emu)}, "read input at native frame rate", "" },
    { "target", HAS_ARG | OPT_FUNC2, {(void*)opt_target}, "specify target file type (\"vcd\", \"svcd\", \"dvd\", \"dv\", \"dv50\", \"pal-vcd\", \"ntsc-svcd\", ...)", "type" },
    { "vsync", HAS_ARG | OPT_INT | OPT_EXPERT, {(void*)&video_sync_method}, "video sync method", "" },
    { "async", HAS_ARG | OPT_INT | OPT_EXPERT, {(void*)&audio_sync_method}, "audio sync method", "" },
    { "adrift_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT, {(void*)&audio_drift_threshold}, "audio drift threshold", "threshold" },
    { "copyts", OPT_BOOL | OPT_EXPERT, {(void*)&copy_ts}, "copy timestamps" },
    { "copytb", OPT_BOOL | OPT_EXPERT, {(void*)&copy_tb}, "copy input stream time base when stream copying" },
    { "shortest", OPT_BOOL | OPT_EXPERT, {(void*)&opt_shortest}, "finish encoding within shortest input" }, //
    { "dts_delta_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT, {(void*)&dts_delta_threshold}, "timestamp discontinuity delta threshold", "threshold" },
    { "xerror", OPT_BOOL, {(void*)&exit_on_error}, "exit on error", "error" },
    { "copyinkf", OPT_BOOL | OPT_EXPERT, {(void*)&copy_initial_nonkeyframes}, "copy initial non-keyframes" },
    { "frames", OPT_INT64 | HAS_ARG | OPT_SPEC, {.off = OFFSET(max_frames)}, "set the number of frames to record", "number" },
    { "tag",   OPT_STRING | HAS_ARG | OPT_SPEC, {.off = OFFSET(codec_tags)}, "force codec tag/fourcc", "fourcc/tag" },
    { "q", HAS_ARG | OPT_EXPERT | OPT_DOUBLE | OPT_SPEC, {.off = OFFSET(qscale)}, "use fixed quality scale (VBR)", "q" },
    { "qscale", HAS_ARG | OPT_EXPERT | OPT_DOUBLE | OPT_SPEC, {.off = OFFSET(qscale)}, "use fixed quality scale (VBR)", "q" },
#if CONFIG_AVFILTER
    { "filter", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(filters)}, "set stream filterchain", "filter_list" },
#endif
    { "stats", OPT_BOOL, {&print_stats}, "print progress report during encoding", },
    { "attach", HAS_ARG | OPT_FUNC2, {(void*)opt_attach}, "add an attachment to the output file", "filename" },
    { "dump_attachment", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(dump_attachment)}, "extract an attachment into a file", "filename" },

    /* video options */
    { "vframes", HAS_ARG | OPT_VIDEO | OPT_FUNC2, {(void*)opt_video_frames}, "set the number of video frames to record", "number" },
    { "r", HAS_ARG | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(frame_rates)}, "set frame rate (Hz value, fraction or abbreviation)", "rate" },
    { "s", HAS_ARG | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(frame_sizes)}, "set frame size (WxH or abbreviation)", "size" },
    { "aspect", HAS_ARG | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(frame_aspect_ratios)}, "set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)", "aspect" },
    { "pix_fmt", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(frame_pix_fmts)}, "set pixel format", "format" },
    { "vn", OPT_BOOL | OPT_VIDEO | OPT_OFFSET, {.off = OFFSET(video_disable)}, "disable video" },
    { "vdt", OPT_INT | HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)&video_discard}, "discard threshold", "n" },
    { "rc_override", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(rc_overrides)}, "rate control override for specific intervals", "override" },
    { "vcodec", HAS_ARG | OPT_VIDEO | OPT_FUNC2, {(void*)opt_video_codec}, "force video codec ('copy' to copy stream)", "codec" },
    { "same_quant", OPT_BOOL | OPT_VIDEO, {(void*)&same_quant},
      "use same quantizer as source (implies VBR)" },
    { "pass", HAS_ARG | OPT_VIDEO, {(void*)opt_pass}, "select the pass number (1 or 2)", "n" },
    { "passlogfile", HAS_ARG | OPT_STRING | OPT_VIDEO, {(void*)&pass_logfilename_prefix}, "select two pass log file name prefix", "prefix" },
    { "deinterlace", OPT_BOOL | OPT_EXPERT | OPT_VIDEO, {(void*)&do_deinterlace},
      "deinterlace pictures" },
    { "vstats", OPT_EXPERT | OPT_VIDEO, {(void*)&opt_vstats}, "dump video coding statistics to file" },
    { "vstats_file", HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)opt_vstats_file}, "dump video coding statistics to file", "file" },
#if CONFIG_AVFILTER
    { "vf", HAS_ARG | OPT_VIDEO | OPT_FUNC2, {(void*)opt_video_filters}, "video filters", "filter list" },
#endif
    { "intra_matrix", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(intra_matrices)}, "specify intra matrix coeffs", "matrix" },
    { "inter_matrix", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_STRING | OPT_SPEC, {.off = OFFSET(inter_matrices)}, "specify inter matrix coeffs", "matrix" },
    { "top", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_INT| OPT_SPEC, {.off = OFFSET(top_field_first)}, "top=1/bottom=0/auto=-1 field first", "" },
    { "dc", OPT_INT | HAS_ARG | OPT_EXPERT | OPT_VIDEO, {(void*)&intra_dc_precision}, "intra_dc_precision", "precision" },
    { "vtag", HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_FUNC2, {(void*)opt_video_tag}, "force video tag/fourcc", "fourcc/tag" },
    { "qphist", OPT_BOOL | OPT_EXPERT | OPT_VIDEO, { (void *)&qp_hist }, "show QP histogram" },
    { "force_fps", OPT_BOOL | OPT_EXPERT | OPT_VIDEO | OPT_SPEC, {.off = OFFSET(force_fps)}, "force the selected framerate, disable the best supported framerate selection" },
    { "streamid", HAS_ARG | OPT_EXPERT | OPT_FUNC2, {(void*)opt_streamid}, "set the value of an outfile streamid", "streamIndex:value" },
    { "force_key_frames", OPT_STRING | HAS_ARG | OPT_EXPERT | OPT_VIDEO | OPT_SPEC, {.off = OFFSET(forced_key_frames)}, "force key frames at specified timestamps", "timestamps" },

    /* audio options */
    { "aframes", HAS_ARG | OPT_AUDIO | OPT_FUNC2, {(void*)opt_audio_frames}, "set the number of audio frames to record", "number" },
    { "aq", HAS_ARG | OPT_AUDIO | OPT_FUNC2, {(void*)opt_audio_qscale}, "set audio quality (codec-specific)", "quality", },
    { "ar", HAS_ARG | OPT_AUDIO | OPT_INT | OPT_SPEC, {.off = OFFSET(audio_sample_rate)}, "set audio sampling rate (in Hz)", "rate" },
    { "ac", HAS_ARG | OPT_AUDIO | OPT_INT | OPT_SPEC, {.off = OFFSET(audio_channels)}, "set number of audio channels", "channels" },
    { "an", OPT_BOOL | OPT_AUDIO | OPT_OFFSET, {.off = OFFSET(audio_disable)}, "disable audio" },
    { "acodec", HAS_ARG | OPT_AUDIO | OPT_FUNC2, {(void*)opt_audio_codec}, "force audio codec ('copy' to copy stream)", "codec" },
    { "atag", HAS_ARG | OPT_EXPERT | OPT_AUDIO | OPT_FUNC2, {(void*)opt_audio_tag}, "force audio tag/fourcc", "fourcc/tag" },
    { "vol", OPT_INT | HAS_ARG | OPT_AUDIO, {(void*)&audio_volume}, "change audio volume (256=normal)" , "volume" }, //
    { "sample_fmt", HAS_ARG | OPT_EXPERT | OPT_AUDIO | OPT_SPEC | OPT_STRING, {.off = OFFSET(sample_fmts)}, "set sample format", "format" },

    /* subtitle options */
    { "sn", OPT_BOOL | OPT_SUBTITLE | OPT_OFFSET, {.off = OFFSET(subtitle_disable)}, "disable subtitle" },
    { "scodec", HAS_ARG | OPT_SUBTITLE | OPT_FUNC2, {(void*)opt_subtitle_codec}, "force subtitle codec ('copy' to copy stream)", "codec" },
    { "stag", HAS_ARG | OPT_EXPERT | OPT_SUBTITLE | OPT_FUNC2, {(void*)opt_subtitle_tag}, "force subtitle tag/fourcc", "fourcc/tag" },

    /* grab options */
    { "isync", OPT_BOOL | OPT_EXPERT | OPT_GRAB, {(void*)&input_sync}, "sync read on input", "" },

    /* muxer options */
    { "muxdelay", OPT_FLOAT | HAS_ARG | OPT_EXPERT   | OPT_OFFSET, {.off = OFFSET(mux_max_delay)}, "set the maximum demux-decode delay", "seconds" },
    { "muxpreload", OPT_FLOAT | HAS_ARG | OPT_EXPERT | OPT_OFFSET, {.off = OFFSET(mux_preload)},   "set the initial demux-decode delay", "seconds" },

    { "bsf", HAS_ARG | OPT_STRING | OPT_SPEC, {.off = OFFSET(bitstream_filters)}, "A comma-separated list of bitstream filters", "bitstream_filters" },

    /* data codec support */
    { "dcodec", HAS_ARG | OPT_DATA | OPT_FUNC2, {(void*)opt_data_codec}, "force data codec ('copy' to copy stream)", "codec" },

    { "default", HAS_ARG | OPT_AUDIO | OPT_VIDEO | OPT_EXPERT, {(void*)opt_default}, "generic catch all option", "" },
    { NULL, },
};

int main(int argc, char **argv)
{
    OptionsContext o = { 0 };
    int64_t ti;

    reset_options(&o);

    av_log_set_flags(AV_LOG_SKIP_REPEATED);
    parse_loglevel(argc, argv, options);

    avcodec_register_all();
#if CONFIG_AVDEVICE
    avdevice_register_all();
#endif
#if CONFIG_AVFILTER
    avfilter_register_all();
#endif
    av_register_all();
    avformat_network_init();

    avio_set_interrupt_cb(decode_interrupt_cb);

    show_banner();

    /* parse options */
    parse_options(&o, argc, argv, options, opt_output_file);

    if(nb_output_files <= 0 && nb_input_files == 0) {
        show_usage();
        av_log(NULL, AV_LOG_WARNING, "Use -h to get full help or, even better, run 'man %s'\n", program_name);
        exit_program(1);
    }

    /* file converter / grab */
    if (nb_output_files <= 0) {
        fprintf(stderr, "At least one output file must be specified\n");
        exit_program(1);
    }

    if (nb_input_files == 0) {
        av_log(NULL, AV_LOG_FATAL, "At least one input file must be specified\n");
        exit_program(1);
    }

    ti = getutime();
    if (transcode(output_files, nb_output_files, input_files, nb_input_files) < 0)
        exit_program(1);
    ti = getutime() - ti;
    if (do_benchmark) {
        int maxrss = getmaxrss() / 1024;
        printf("bench: utime=%0.3fs maxrss=%ikB\n", ti / 1000000.0, maxrss);
    }

    exit_program(0);
    return 0;
}