question about multipass first pass

Joined: 25 Aug 2009 Posts: 1

When going to multipass first pass, what is the bit rate importance there? Since when I go to multipass nthpass, and choose a desired bit rate, file will be of difference size normally, so I simply don't understand effect of bit rate in multipass first pass.

Thanks.

Developer/Maintainer Joined: 17 Dec 2007 Posts: 22

First pass is made for video analyze, and for usefulness of this analyze information it is better when target bitrate of first pass is near the target bitrate of second pass (otherwise resulted quality can be lower).