`qemu-img info` reports an incorrect actual-size when the underlying posix filesystem has transparent compression

qemu-img info reports the same thing as `du`*1024:

$ qemu-img info --output json ./my.qcow2  | jq '."actual-size"'
558619648

$ du ./my.qcow2
545527	./my.qcow2

$ echo $((558619648 / 545527))
1024

and this is correct in terms of bytes on disk, but due to transparent compression implemented by the filesystem, it is not the actual byte count:

$ du -h --apparent-size ./my.qcow2
1346568192	my.qcow2