ffmpeg -i sintel.y4m -c:v libx264 -profile high -pixel_format nv12 -preset veryfast -b:v 6000k -c:a copy x264_veryfast.mkv
ffmpeg -i sintel.y4m -i x264_veryfast.mkv -lavfi "ssim;[0:v][1:v]psnr" -f null -
	SSIM Y:0.995538 (23.504484) U:0.996561 (24.635538) V:0.996341 (24.366190) All:0.995842 (23.811335)
	PSNR y:50.313784 u:53.650778 v:53.276448 average:51.132360 min:44.367678 max:inf

ffmpeg -i sintel.y4m -c:v h264_nvenc -profile high -pixel_format nv12 -preset bd -2pass 1 -rc vbr -b:v 6000k nvenc_bd.mp4
ffmpeg -i sintel.y4m -i nvenc_bd.mp4 -lavfi "ssim;[0:v][1:v]psnr" -f null -
	SSIM Y:0.995116 (23.111841) U:0.996827 (24.985902) V:0.996609 (24.696179) All:0.995650 (23.614843)
	PSNR y:49.162456 u:54.159645 v:53.761447 average:50.257082 min:43.915031 max:inf

ffmpeg -i sintel.y4m -c:v h264_nvenc -profile high -pixel_format nv12 -preset ll -2pass 1 -rc vbr -b:v 6000k nvenc_ll.mp4
ffmpeg -i sintel.y4m -i nvenc_ll.mp4 -lavfi "ssim;[0:v][1:v]psnr" -f null -
	SSIM Y:0.995110 (23.107114) U:0.996828 (24.986406) V:0.996610 (24.698570) All:0.995647 (23.611677)
	PSNR y:49.142959 u:54.157927 v:53.761745 average:50.240258 min:44.021892 max:inf