I tried to encode video files using FFMPEG built with AMF support and found some unexpected behavior.
I tried to get maximum quality with an encoded bitrate limit. Some videos are encoded pretty nice, but some are encoded with bitrate too much over limit. For example, the desired 8M bitrate encoded as 98M.
The command line used is
ffmpeg.exe -i input.y4m -c:v hevc_amf -quality quality -usage transcoding -b:v 8M -bufsize 16M -maxrate 12M output.hevc
Tried many other parameters but none of them get encoded bitrate to the limits.
Driver version: 18.Q1.1-March22
Board: Vega Frontier Edition
Could you suggest what can be wrong?