How to implement capped crf

[mdsohelmia]

ffmpeg -I Sintel.mp4 -c:v libx264 -crf 23 -maxrate 2M -bufsize 4M -preset medium Sintel_CRF23_2M.mp4

[asticode]

You need to provide a dictionary containing the proper options in the CodecContext.Open() method (I've omitted error handling for readability purposes below however you should handle error when needed):

// Create dictionary
d := astiav.NewDictionary()

// Make sure to free it
defer d.Free()

// Parse dictionary
d.ParseString("preset=medium,crf=23", "=", ",", 0)

// Open codec context with the dictionary
encoderCtx.Open(codec, d)