DLNAUtil

int DLNAUtil_GetMediaThumbnailAtPath(char * fromMediaPath, char * toMediaPath, float atDuration) {
    float duration = DLNAUtil_GetMediaDurationSecAtPath(fromMediaPath);
    float targetDuration = 0;

    AVCodecContext *codec_ctx;
    AVCodec *codec;

    int video_stream_index;


    if (atDuration < 0) targetDuration = duration / 2;
    else if (atDuration > duration) targetDuration = duration;
    else targetDuration = atDuration;

    init();
    AVFormatContext *fmt_ctx = NULL;
    int ret = av_open_input_file(&fmt_ctx, fromMediaPath, NULL, 0, NULL);
    if (ret >= 0 && fmt_ctx) {
        codec = NULL;
        codec_ctx = NULL;
        video_stream_index  = -1;
        for (int i = 0; i < fmt_ctx->nb_streams; i++) {
            codec_ctx = fmt_ctx->streams[i]->codec;
            if (CODEC_TYPE_VIDEO != codec_ctx->codec_type) {
                continue;
            }
            if (NULL == (codec = avcodec_find_decoder(codec_ctx->codec_id))) {
                printf("\n%s, codec not found.\n", __func__);
                continue;
            }
            if (0 != (avcodec_open(codec_ctx, codec))) {
                printf("\n%s, can not open codec\n", __func__);
                codec = NULL;
                continue;
            }
            video_stream_index = i;
            break;
        }
        if (video_stream_index == -1 || codec_ctx->width == 0 || codec_ctx->height == 0) {
            if (codec != NULL) {
                printf("\n%s, codec:%d, %dx%d\n", __func__, codec, codec_ctx->width, codec_ctx->height);
                avcodec_close(codec_ctx);
            }
            av_close_input_file(fmt_ctx);
            return -1;
        }
        printf("\n%s, videoIndex:%d, codec:%d, %dx%d\n", __func__, video_stream_index, codec, codec_ctx->width, codec_ctx->height);
        return video_stream_index   ;


        int ret2 = av_seek_frame(fmt_ctx, 0, (targetDuration * AV_TIME_BASE), 0);
        if (ret2 >= 0) {
            AVPacket *pkt = NULL;
            //int ret3 = av_read_frame(fmt_ctx, pkt);
            while(av_read_frame(fmt_ctx, pkt) >= 0) {
                if (pkt->stream_index == 0);
            }
        }

    }





    return -1;
}