void avformat_free_context(AVFormatContext *s)
{
    int i, j;
    AVStream *st;

    av_opt_free(s);
    if (s->iformat && s->iformat->priv_class && s->priv_data)
        av_opt_free(s->priv_data);

    for (i = 0; i < s->nb_streams; i++) {
        /* free all data in a stream component */
        st = s->streams[i];

        for (j = 0; j < st->nb_side_data; j++)
            av_freep(&st->side_data[j].data);
        av_freep(&st->side_data);
        st->nb_side_data = 0;

        if (st->parser) {
            av_parser_close(st->parser);
        }
        if (st->attached_pic.data)
            av_free_packet(&st->attached_pic);
        av_dict_free(&st->metadata);
        av_freep(&st->probe_data.buf);
        av_free(st->index_entries);
        av_free(st->codec->extradata);
        av_free(st->codec->subtitle_header);
        av_free(st->codec);
        av_free(st->priv_data);
        av_free(st->info);
        av_free(st);
    }
    for (i = s->nb_programs - 1; i >= 0; i--) {
        av_dict_free(&s->programs[i]->metadata);
        av_freep(&s->programs[i]->stream_index);
        av_freep(&s->programs[i]);
    }
    av_freep(&s->programs);
    av_freep(&s->priv_data);
    while (s->nb_chapters--) {
        av_dict_free(&s->chapters[s->nb_chapters]->metadata);
        av_free(s->chapters[s->nb_chapters]);
    }
    av_freep(&s->chapters);
    av_dict_free(&s->metadata);
    av_freep(&s->streams);
    av_freep(&s->internal);
    av_free(s);
}