avcodec quality settings

Is there any explanation of the settings in the avcodec lib AVCodec and AVCodecContext structs?

The bit rate and gop are fairly obvious but I'm having problems mapping the rest onto the ffmpeg and x264 presets.

For example the high bit rate setting in ffmpeg is dumped as:

vcodec=mpeg4:mbd=2:mv0:trell:v4mv:开发者_高级运维cbp:last_pred=3:predia=2:dia=2:vmax_b_frames=2:vb_strategy=1:precmp=2:cmp=2:subcmp=2:preme=2:qns=2

How do I set the avcodec lib to the same configuration?

You can check the options.c file in libavcodec. There are a lot of explanations, here an example:

{"cbp", "use rate distortion optimization for cbp", 0, FF_OPT_TYPE_CONST, {.dbl = CODEC_FLAG_CBP_RD }, INT_MIN, INT_MAX, V|E, "flags"},

Hope it helps!