ffmpeg - Conversions - Convert H264 to AV1 - libaom - A minimum and maximum bitrate

libaom-av1 allows a minimum and maximum bitrate can be specified, instead of a quality target.

This method is useful for bulk encoding videos in a generally consistent fashion.

NOTE: When muxing into MP4, you may want to add -movflags +faststart to the output parameters if the intended use for the resulting file is streaming.

time ffmpeg -i a.mp4 -c:v libaom-av1 -minrate 500k -b:v 2000k -maxrate 2500k -f mp4 out.mp4

returns:

...
real	107m58.989s
user	618m30.322s
sys	0m32.327s

NOTE:

Input test size: 75.5M
Output test size: 4.9M

NOTE: The bitrate limit by the -b:v where the bitrate MUST be non-zero.