[FFmpeg-devel] how to add configuration option to ffmepg

[llj]

Hi, dear ffmpeg developer,
below is a peace of code in libx264.c.


static av_cold int X264_init(AVCodecContext *avctx)
{
    X264Context *x4 = avctx->priv_data;
    int sw,sh;


    if (avctx->global_quality > 0)
        av_log(avctx, AV_LOG_WARNING, "-qscale is ignored, -crf is recommended.\n");


#if HAVE_STUDY
    //my study code.  
#endif


    x264_param_default(&x4->params);


    x4->params.b_deblocking_filter         = avctx->flags & CODEC_FLAG_LOOP_FILTER;
    ......
}


I want to add some of my code which control by HAVE_STUDY micro, I hope that it is close by default, and when I configure the ffmpeg with --enable-study option, the HAVE_STUDY is true, how can I reach this aim?
can someone kindly help me?