The official documentation, even the latest, defines only two groups of -q setting for VBR rather than the three that exist in reality, and it does not divulge that certain pairs like -q8/7 and -q5/6 are seemingly identical. Things like this are why we would be happy to see the developers update it officially with the latest information rather than us having to ask them lots of questions and guess things that we are not told.
↧