{"aq_strength","specify aq strength",OFFSET(aq_strength),FF_OPT_TYPE_FLOAT,1.0,0,FLT_MAX,V|E},
{"rc_lookahead","specify number of frames to look ahead for frametype",OFFSET(rc_lookahead),FF_OPT_TYPE_INT,40,0,INT_MAX,V|E},
{"ssim","ssim will be calculated during encoding",0,FF_OPT_TYPE_CONST,CODEC_FLAG2_SSIM,INT_MIN,INT_MAX,V|E,"flags2"},
{"intra_refresh","use periodic insertion of intra blocks instead of keyframes",0,FF_OPT_TYPE_CONST,CODEC_FLAG2_INTRA_REFRESH,INT_MIN,INT_MAX,V|E,"flags2"},
{"crf_max","in crf mode, prevents vbv from lowering quality beyond this point",OFFSET(crf_max),FF_OPT_TYPE_FLOAT,DEFAULT,0,51,V|E},