cmdutils.c

        else if (t->key[0] == prefix &&
                 av_opt_find(&cc, t->key + 1, NULL, flags,
                             AV_OPT_SEARCH_FAKE_OBJ))
            av_dict_set(&ret, t->key + 1, t->value, 0);

        if (p)
            *p = ':';
    }
    return ret;
}

AVDictionary **setup_find_stream_info_opts(AVFormatContext *s,
                                           AVDictionary *codec_opts)
{
    int i;
    AVDictionary **opts;

    if (!s->nb_streams)
        return NULL;
    opts = av_mallocz(s->nb_streams * sizeof(*opts));
    if (!opts) {
        av_log(NULL, AV_LOG_ERROR,
               "Could not alloc memory for stream options.\n");
        return NULL;
    }
    for (i = 0; i < s->nb_streams; i++)
        opts[i] = filter_codec_opts(codec_opts, s->streams[i]->codec->codec_id,
                                    s, s->streams[i]);
    return opts;
}

#if CONFIG_AVFILTER

static int sink_init(AVFilterContext *ctx, const char *args, void *opaque)
{
    SinkContext *priv = ctx->priv;

    if (!opaque)
        return AVERROR(EINVAL);
    *priv = *(SinkContext *)opaque;

    return 0;
}

static void null_end_frame(AVFilterLink *inlink) { }

static int sink_query_formats(AVFilterContext *ctx)
{
    SinkContext *priv = ctx->priv;
    enum PixelFormat pix_fmts[] = { priv->pix_fmt, PIX_FMT_NONE };

    avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
    return 0;
}

AVFilter sink = {
    .name      = "sink",
    .priv_size = sizeof(SinkContext),
    .init      = sink_init,

    .query_formats = sink_query_formats,

    .inputs    = (AVFilterPad[]) {{ .name          = "default",
                                    .type          = AVMEDIA_TYPE_VIDEO,
                                    .end_frame     = null_end_frame,
                                    .min_perms     = AV_PERM_READ, },
                                  { .name = NULL }},
    .outputs   = (AVFilterPad[]) {{ .name = NULL }},
};

int get_filtered_video_frame(AVFilterContext *ctx, AVFrame *frame,
                             AVFilterBufferRef **picref_ptr, AVRational *tb)
{
    int ret;
    AVFilterBufferRef *picref;

    if ((ret = avfilter_request_frame(ctx->inputs[0])) < 0)
        return ret;
    if (!(picref = ctx->inputs[0]->cur_buf))
        return AVERROR(ENOENT);
    *picref_ptr = picref;
    ctx->inputs[0]->cur_buf = NULL;
    *tb = ctx->inputs[0]->time_base;

    memcpy(frame->data,     picref->data,     sizeof(frame->data));
    memcpy(frame->linesize, picref->linesize, sizeof(frame->linesize));
    frame->interlaced_frame    = picref->video->interlaced;
    frame->top_field_first     = picref->video->top_field_first;
    frame->key_frame           = picref->video->key_frame;
    frame->pict_type           = picref->video->pict_type;
    frame->sample_aspect_ratio = picref->video->pixel_aspect;

    return 1;
}

#endif /* CONFIG_AVFILTER */

void *grow_array(void *array, int elem_size, int *size, int new_size)
{
    if (new_size >= INT_MAX / elem_size) {
        av_log(NULL, AV_LOG_ERROR, "Array too big.\n");
        exit_program(1);
    }
    if (*size < new_size) {
        uint8_t *tmp = av_realloc(array, new_size*elem_size);
        if (!tmp) {
            av_log(NULL, AV_LOG_ERROR, "Could not alloc buffer.\n");
            exit_program(1);
        }
        memset(tmp + *size*elem_size, 0, (new_size-*size) * elem_size);
        *size = new_size;
        return tmp;
    }
    return array;
}