avconv_opt.c

    OptionsContext *o = optctx;
    return parse_option(o, "filter:a", arg, options);
}

static int opt_vsync(void *optctx, const char *opt, const char *arg)
{
    if      (!av_strcasecmp(arg, "cfr"))         video_sync_method = VSYNC_CFR;
    else if (!av_strcasecmp(arg, "vfr"))         video_sync_method = VSYNC_VFR;
    else if (!av_strcasecmp(arg, "passthrough")) video_sync_method = VSYNC_PASSTHROUGH;

    if (video_sync_method == VSYNC_AUTO)
        video_sync_method = parse_number_or_die("vsync", arg, OPT_INT, VSYNC_AUTO, VSYNC_VFR);
    return 0;
}

static int opt_channel_layout(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    char layout_str[32];
    char *stream_str;
    char *ac_str;
    int ret, channels, ac_str_size;
    uint64_t layout;

    layout = av_get_channel_layout(arg);
    if (!layout) {
        av_log(NULL, AV_LOG_ERROR, "Unknown channel layout: %s\n", arg);
        return AVERROR(EINVAL);
    }
    snprintf(layout_str, sizeof(layout_str), "%"PRIu64, layout);
    ret = opt_default(NULL, opt, layout_str);
    if (ret < 0)
        return ret;

    /* set 'ac' option based on channel layout */
    channels = av_get_channel_layout_nb_channels(layout);
    snprintf(layout_str, sizeof(layout_str), "%d", channels);
    stream_str = strchr(opt, ':');
    ac_str_size = 3 + (stream_str ? strlen(stream_str) : 0);
    ac_str = av_mallocz(ac_str_size);
    if (!ac_str)
        return AVERROR(ENOMEM);
    av_strlcpy(ac_str, "ac", 3);
    if (stream_str)
        av_strlcat(ac_str, stream_str, ac_str_size);
    ret = parse_option(o, ac_str, layout_str, options);
    av_free(ac_str);

    return ret;
}

static int opt_audio_qscale(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "q:a", arg, options);
}

static int opt_filter_complex(void *optctx, const char *opt, const char *arg)
{
    GROW_ARRAY(filtergraphs, nb_filtergraphs);
    if (!(filtergraphs[nb_filtergraphs - 1] = av_mallocz(sizeof(*filtergraphs[0]))))
        return AVERROR(ENOMEM);
    filtergraphs[nb_filtergraphs - 1]->index      = nb_filtergraphs - 1;
    filtergraphs[nb_filtergraphs - 1]->graph_desc = av_strdup(arg);
    if (!filtergraphs[nb_filtergraphs - 1]->graph_desc)
        return AVERROR(ENOMEM);
    return 0;
}

static int opt_filter_complex_script(void *optctx, const char *opt, const char *arg)
{
    uint8_t *graph_desc = read_file(arg);
    if (!graph_desc)
        return AVERROR(EINVAL);

    GROW_ARRAY(filtergraphs, nb_filtergraphs);
    if (!(filtergraphs[nb_filtergraphs - 1] = av_mallocz(sizeof(*filtergraphs[0]))))
        return AVERROR(ENOMEM);
    filtergraphs[nb_filtergraphs - 1]->index      = nb_filtergraphs - 1;
    filtergraphs[nb_filtergraphs - 1]->graph_desc = graph_desc;
    return 0;
}

void show_help_default(const char *opt, const char *arg)
{
    /* per-file options have at least one of those set */
    const int per_file = OPT_SPEC | OPT_OFFSET | OPT_PERFILE;
    int show_advanced = 0, show_avoptions = 0;

    if (opt && *opt) {
        if (!strcmp(opt, "long"))
            show_advanced = 1;
        else if (!strcmp(opt, "full"))
            show_advanced = show_avoptions = 1;
        else
            av_log(NULL, AV_LOG_ERROR, "Unknown help option '%s'.\n", opt);
    }

    show_usage();

    printf("Getting help:\n"
           "    -h      -- print basic options\n"
           "    -h long -- print more options\n"
           "    -h full -- print all options (including all format and codec specific options, very long)\n"
           "    See man %s for detailed description of the options.\n"
           "\n", program_name);

    show_help_options(options, "Print help / information / capabilities:",
                      OPT_EXIT, 0, 0);

    show_help_options(options, "Global options (affect whole program "
                      "instead of just one file:",
                      0, per_file | OPT_EXIT | OPT_EXPERT, 0);
    if (show_advanced)
        show_help_options(options, "Advanced global options:", OPT_EXPERT,
                          per_file | OPT_EXIT, 0);

    show_help_options(options, "Per-file main options:", 0,
                      OPT_EXPERT | OPT_AUDIO | OPT_VIDEO | OPT_SUBTITLE |
                      OPT_EXIT, per_file);
    if (show_advanced)
        show_help_options(options, "Advanced per-file options:",
                          OPT_EXPERT, OPT_AUDIO | OPT_VIDEO | OPT_SUBTITLE, per_file);

    show_help_options(options, "Video options:",
                      OPT_VIDEO, OPT_EXPERT | OPT_AUDIO, 0);
    if (show_advanced)
        show_help_options(options, "Advanced Video options:",
                          OPT_EXPERT | OPT_VIDEO, OPT_AUDIO, 0);

    show_help_options(options, "Audio options:",
                      OPT_AUDIO, OPT_EXPERT | OPT_VIDEO, 0);
    if (show_advanced)
        show_help_options(options, "Advanced Audio options:",
                          OPT_EXPERT | OPT_AUDIO, OPT_VIDEO, 0);
    show_help_options(options, "Subtitle options:",
                      OPT_SUBTITLE, 0, 0);
    printf("\n");

    if (show_avoptions) {
        int flags = AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_ENCODING_PARAM;
        show_help_children(avcodec_get_class(), flags);
        show_help_children(avformat_get_class(), flags);
        show_help_children(sws_get_class(), flags);
        show_help_children(avfilter_get_class(), AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM);
    }
}

void show_usage(void)
{
    printf("Hyper fast Audio and Video encoder\n");
    printf("usage: %s [options] [[infile options] -i infile]... {[outfile options] outfile}...\n", program_name);
    printf("\n");
}

enum OptGroup {
    GROUP_OUTFILE,
    GROUP_INFILE,
};

static const OptionGroupDef groups[] = {
    [GROUP_OUTFILE] = { "output file",  NULL, OPT_OUTPUT },
    [GROUP_INFILE]  = { "input file",   "i",  OPT_INPUT },
};

static int open_files(OptionGroupList *l, const char *inout,
                      int (*open_file)(OptionsContext*, const char*))
{
    int i, ret;

    for (i = 0; i < l->nb_groups; i++) {
        OptionGroup *g = &l->groups[i];
        OptionsContext o;

        init_options(&o);
        o.g = g;

        ret = parse_optgroup(&o, g);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error parsing options for %s file "
                   "%s.\n", inout, g->arg);
            return ret;
        }

        av_log(NULL, AV_LOG_DEBUG, "Opening an %s file: %s.\n", inout, g->arg);
        ret = open_file(&o, g->arg);
        uninit_options(&o);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error opening %s file %s.\n",
                   inout, g->arg);
            return ret;
        }
        av_log(NULL, AV_LOG_DEBUG, "Successfully opened the file.\n");
    }

    return 0;
}

int avconv_parse_options(int argc, char **argv)
{
    OptionParseContext octx;
    uint8_t error[128];
    int ret;

    memset(&octx, 0, sizeof(octx));

    /* split the commandline into an internal representation */
    ret = split_commandline(&octx, argc, argv, options, groups,
                            FF_ARRAY_ELEMS(groups));
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error splitting the argument list: ");
        goto fail;
    }

    /* apply global options */
    ret = parse_optgroup(NULL, &octx.global_opts);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error parsing global options: ");
        goto fail;
    }

    /* open input files */
    ret = open_files(&octx.groups[GROUP_INFILE], "input", open_input_file);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error opening input files: ");
        goto fail;
    }

    /* open output files */
    ret = open_files(&octx.groups[GROUP_OUTFILE], "output", open_output_file);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error opening output files: ");
        goto fail;
    }

fail:
    uninit_parse_context(&octx);
    if (ret < 0) {
        av_strerror(ret, error, sizeof(error));
        av_log(NULL, AV_LOG_FATAL, "%s\n", error);
    }
    return ret;
}

#define OFFSET(x) offsetof(OptionsContext, x)
const OptionDef options[] = {
    /* main options */
#include "cmdutils_common_opts.h"
    { "f",              HAS_ARG | OPT_STRING | OPT_OFFSET |
                        OPT_INPUT | OPT_OUTPUT,                      { .off       = OFFSET(format) },
        "force format", "fmt" },
    { "y",              OPT_BOOL,                                    {              &file_overwrite },
        "overwrite output files" },
    { "n",              OPT_BOOL,                                    {              &file_skip },
        "never overwrite output files" },
    { "c",              HAS_ARG | OPT_STRING | OPT_SPEC |
                        OPT_INPUT | OPT_OUTPUT,                      { .off       = OFFSET(codec_names) },
        "codec name", "codec" },
    { "codec",          HAS_ARG | OPT_STRING | OPT_SPEC |
                        OPT_INPUT | OPT_OUTPUT,                      { .off       = OFFSET(codec_names) },
        "codec name", "codec" },
    { "pre",            HAS_ARG | OPT_STRING | OPT_SPEC |
                        OPT_OUTPUT,                                  { .off       = OFFSET(presets) },
        "preset name", "preset" },
    { "map",            HAS_ARG | OPT_EXPERT | OPT_PERFILE |
                        OPT_OUTPUT,                                  { .func_arg = opt_map },
        "set input stream mapping",
        "[-]input_file_id[:stream_specifier][,sync_file_id[:stream_specifier]]" },
    { "map_metadata",   HAS_ARG | OPT_STRING | OPT_SPEC |
                        OPT_OUTPUT,                                  { .off       = OFFSET(metadata_map) },
        "set metadata information of outfile from infile",
        "outfile[,metadata]:infile[,metadata]" },
    { "map_chapters",   HAS_ARG | OPT_INT | OPT_EXPERT | OPT_OFFSET |
                        OPT_OUTPUT,                                  { .off = OFFSET(chapters_input_file) },
        "set chapters mapping", "input_file_index" },
    { "t",              HAS_ARG | OPT_TIME | OPT_OFFSET |
                        OPT_INPUT | OPT_OUTPUT,                      { .off = OFFSET(recording_time) },
        "record or transcode \"duration\" seconds of audio/video",
        "duration" },
    { "fs",             HAS_ARG | OPT_INT64 | OPT_OFFSET | OPT_OUTPUT, { .off = OFFSET(limit_filesize) },
        "set the limit file size in bytes", "limit_size" },
    { "ss",             HAS_ARG | OPT_TIME | OPT_OFFSET |
                        OPT_INPUT | OPT_OUTPUT,                      { .off = OFFSET(start_time) },
        "set the start time offset", "time_off" },
    { "accurate_seek",  OPT_BOOL | OPT_OFFSET | OPT_EXPERT |
                        OPT_INPUT,                                   { .off = OFFSET(accurate_seek) },
        "enable/disable accurate seeking with -ss" },
    { "itsoffset",      HAS_ARG | OPT_TIME | OPT_OFFSET |
                        OPT_EXPERT | OPT_INPUT,                      { .off = OFFSET(input_ts_offset) },
        "set the input ts offset", "time_off" },
    { "itsscale",       HAS_ARG | OPT_DOUBLE | OPT_SPEC |
                        OPT_EXPERT | OPT_INPUT,                      { .off = OFFSET(ts_scale) },
        "set the input ts scale", "scale" },
    { "metadata",       HAS_ARG | OPT_STRING | OPT_SPEC | OPT_OUTPUT, { .off = OFFSET(metadata) },
        "add metadata", "string=string" },
    { "dframes",        HAS_ARG | OPT_PERFILE | OPT_EXPERT |
                        OPT_OUTPUT,                                  { .func_arg = opt_data_frames },
        "set the number of data frames to record", "number" },
    { "benchmark",      OPT_BOOL | OPT_EXPERT,                       { &do_benchmark },
        "add timings for benchmarking" },
    { "timelimit",      HAS_ARG | OPT_EXPERT,                        { .func_arg = opt_timelimit },
        "set max runtime in seconds", "limit" },
    { "dump",           OPT_BOOL | OPT_EXPERT,                       { &do_pkt_dump },
        "dump each input packet" },
    { "hex",            OPT_BOOL | OPT_EXPERT,                       { &do_hex_dump },
        "when dumping packets, also dump the payload" },
    { "re",             OPT_BOOL | OPT_EXPERT | OPT_OFFSET |
                        OPT_INPUT,                                   { .off = OFFSET(rate_emu) },
        "read input at native frame rate", "" },
    { "target",         HAS_ARG | OPT_PERFILE | OPT_OUTPUT,          { .func_arg = opt_target },
        "specify target file type (\"vcd\", \"svcd\", \"dvd\","
        " \"dv\", \"dv50\", \"pal-vcd\", \"ntsc-svcd\", ...)", "type" },
    { "vsync",          HAS_ARG | OPT_EXPERT,                        { opt_vsync },
        "video sync method", "" },
    { "async",          HAS_ARG | OPT_INT | OPT_EXPERT,              { &audio_sync_method },
        "audio sync method", "" },
    { "adrift_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT,          { &audio_drift_threshold },
        "audio drift threshold", "threshold" },
    { "copyts",         OPT_BOOL | OPT_EXPERT,                       { &copy_ts },
        "copy timestamps" },
    { "copytb",         OPT_BOOL | OPT_EXPERT,                       { &copy_tb },
        "copy input stream time base when stream copying" },
    { "shortest",       OPT_BOOL | OPT_EXPERT | OPT_OFFSET |
                        OPT_OUTPUT,                                  { .off = OFFSET(shortest) },
        "finish encoding within shortest input" },
    { "dts_delta_threshold", HAS_ARG | OPT_FLOAT | OPT_EXPERT,       { &dts_delta_threshold },
        "timestamp discontinuity delta threshold", "threshold" },
    { "xerror",         OPT_BOOL | OPT_EXPERT,                       { &exit_on_error },
        "exit on error", "error" },
    { "copyinkf",       OPT_BOOL | OPT_EXPERT | OPT_SPEC |
                        OPT_OUTPUT,                                  { .off = OFFSET(copy_initial_nonkeyframes) },
        "copy initial non-keyframes" },
    { "frames",         OPT_INT64 | HAS_ARG | OPT_SPEC | OPT_OUTPUT, { .off = OFFSET(max_frames) },
        "set the number of frames to record", "number" },
    { "tag",            OPT_STRING | HAS_ARG | OPT_SPEC |
                        OPT_EXPERT | OPT_OUTPUT | OPT_INPUT,         { .off = OFFSET(codec_tags) },
        "force codec tag/fourcc", "fourcc/tag" },
    { "q",              HAS_ARG | OPT_EXPERT | OPT_DOUBLE |
                        OPT_SPEC | OPT_OUTPUT,                       { .off = OFFSET(qscale) },
        "use fixed quality scale (VBR)", "q" },
    { "qscale",         HAS_ARG | OPT_EXPERT | OPT_DOUBLE |
                        OPT_SPEC | OPT_OUTPUT,                       { .off = OFFSET(qscale) },
        "use fixed quality scale (VBR)", "q" },
    { "filter",         HAS_ARG | OPT_STRING | OPT_SPEC | OPT_OUTPUT, { .off = OFFSET(filters) },
        "set stream filterchain", "filter_list" },
    { "filter_script",  HAS_ARG | OPT_STRING | OPT_SPEC | OPT_OUTPUT, { .off = OFFSET(filter_scripts) },
        "read stream filtergraph description from a file", "filename" },
    { "filter_complex", HAS_ARG | OPT_EXPERT,                        { .func_arg = opt_filter_complex },
        "create a complex filtergraph", "graph_description" },
    { "filter_complex_script", HAS_ARG | OPT_EXPERT,                 { .func_arg = opt_filter_complex_script },
        "read complex filtergraph description from a file", "filename" },
    { "stats",          OPT_BOOL,                                    { &print_stats },
        "print progress report during encoding", },
    { "attach",         HAS_ARG | OPT_PERFILE | OPT_EXPERT |
                        OPT_OUTPUT,                                  { .func_arg = opt_attach },
        "add an attachment to the output file", "filename" },
    { "dump_attachment", HAS_ARG | OPT_STRING | OPT_SPEC |
                         OPT_EXPERT | OPT_INPUT,                     { .off = OFFSET(dump_attachment) },
        "extract an attachment into a file", "filename" },

    /* video options */
    { "vframes",      OPT_VIDEO | HAS_ARG  | OPT_PERFILE | OPT_OUTPUT,           { .func_arg = opt_video_frames },
        "set the number of video frames to record", "number" },
    { "r",            OPT_VIDEO | HAS_ARG  | OPT_STRING | OPT_SPEC |
                      OPT_INPUT | OPT_OUTPUT,                                    { .off = OFFSET(frame_rates) },
        "set frame rate (Hz value, fraction or abbreviation)", "rate" },
    { "s",            OPT_VIDEO | HAS_ARG  | OPT_STRING | OPT_SPEC |
                      OPT_INPUT | OPT_OUTPUT,                                    { .off = OFFSET(frame_sizes) },
        "set frame size (WxH or abbreviation)", "size" },
    { "aspect",       OPT_VIDEO | HAS_ARG  | OPT_STRING | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(frame_aspect_ratios) },
        "set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)", "aspect" },
    { "pix_fmt",      OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_STRING | OPT_SPEC |
                      OPT_INPUT | OPT_OUTPUT,                                    { .off = OFFSET(frame_pix_fmts) },
        "set pixel format", "format" },
    { "vn",           OPT_VIDEO | OPT_BOOL  | OPT_OFFSET | OPT_OUTPUT,           { .off = OFFSET(video_disable) },
        "disable video" },
    { "vdt",          OPT_VIDEO | OPT_INT | HAS_ARG | OPT_EXPERT ,               { &video_discard },
        "discard threshold", "n" },
    { "rc_override",  OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_STRING | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(rc_overrides) },
        "rate control override for specific intervals", "override" },
    { "vcodec",       OPT_VIDEO | HAS_ARG  | OPT_PERFILE | OPT_INPUT |
                      OPT_OUTPUT,                                                { .func_arg = opt_video_codec },
        "force video codec ('copy' to copy stream)", "codec" },
    { "pass",         OPT_VIDEO | HAS_ARG | OPT_SPEC | OPT_INT | OPT_OUTPUT,     { .off = OFFSET(pass) },
        "select the pass number (1 or 2)", "n" },
    { "passlogfile",  OPT_VIDEO | HAS_ARG | OPT_STRING | OPT_EXPERT | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(passlogfiles) },
        "select two pass log file name prefix", "prefix" },
    { "vstats",       OPT_VIDEO | OPT_EXPERT ,                                   { &opt_vstats },
        "dump video coding statistics to file" },
    { "vstats_file",  OPT_VIDEO | HAS_ARG | OPT_EXPERT ,                         { opt_vstats_file },
        "dump video coding statistics to file", "file" },
    { "vf",           OPT_VIDEO | HAS_ARG  | OPT_PERFILE | OPT_OUTPUT,           { .func_arg = opt_video_filters },
        "video filters", "filter list" },
    { "intra_matrix", OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_STRING | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(intra_matrices) },
        "specify intra matrix coeffs", "matrix" },
    { "inter_matrix", OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_STRING | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(inter_matrices) },
        "specify inter matrix coeffs", "matrix" },
    { "top",          OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_INT| OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(top_field_first) },
        "top=1/bottom=0/auto=-1 field first", "" },
    { "dc",           OPT_VIDEO | OPT_INT | HAS_ARG | OPT_EXPERT ,               { &intra_dc_precision },
        "intra_dc_precision", "precision" },
    { "vtag",         OPT_VIDEO | HAS_ARG | OPT_EXPERT  | OPT_PERFILE |
                      OPT_OUTPUT,                                                { .func_arg = opt_video_tag },
        "force video tag/fourcc", "fourcc/tag" },
    { "qphist",       OPT_VIDEO | OPT_BOOL | OPT_EXPERT ,                        { &qp_hist },
        "show QP histogram" },
    { "force_fps",    OPT_VIDEO | OPT_BOOL | OPT_EXPERT  | OPT_SPEC |
                      OPT_OUTPUT,                                                { .off = OFFSET(force_fps) },
        "force the selected framerate, disable the best supported framerate selection" },
    { "streamid",     OPT_VIDEO | HAS_ARG | OPT_EXPERT | OPT_PERFILE |
                      OPT_OUTPUT,                                                { .func_arg = opt_streamid },
        "set the value of an outfile streamid", "streamIndex:value" },
    { "force_key_frames", OPT_VIDEO | OPT_STRING | HAS_ARG | OPT_EXPERT |
                          OPT_SPEC | OPT_OUTPUT,                                 { .off = OFFSET(forced_key_frames) },
        "force key frames at specified timestamps", "timestamps" },
    { "hwaccel",          OPT_VIDEO | OPT_STRING | HAS_ARG | OPT_EXPERT |
                          OPT_SPEC | OPT_INPUT,                                  { .off = OFFSET(hwaccels) },
        "use HW accelerated decoding", "hwaccel name" },
    { "hwaccel_device",   OPT_VIDEO | OPT_STRING | HAS_ARG | OPT_EXPERT |
                          OPT_SPEC | OPT_INPUT,                                  { .off = OFFSET(hwaccel_devices) },
        "select a device for HW acceleration" "devicename" },
    { "autorotate",       HAS_ARG | OPT_BOOL | OPT_SPEC |
                          OPT_EXPERT | OPT_INPUT,                                { .off = OFFSET(autorotate) },
        "automatically insert correct rotate filters" },

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

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

    /* grab options */
    { "isync", OPT_BOOL | OPT_EXPERT, { &input_sync }, "this option is deprecated and does nothing", "" },

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

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

    /* data codec support */
    { "dcodec", HAS_ARG | OPT_DATA | OPT_PERFILE | OPT_EXPERT | OPT_INPUT | OPT_OUTPUT, { .func_arg = opt_data_codec },
        "force data codec ('copy' to copy stream)", "codec" },

    { NULL, },
};