Thread: Mpeg 2 Bitrate
11-22-2006 07:08 AM #1
Mpeg 2 Bitrate
There is a lot of talk from Sony about using Mpeg 2 compression on their Blu-ray discs at a bitrate of 18mbps.
I checked a few of my DVD's and they were all around 5mbps bitrate using Mpeg 2. 18mbps is 3.5 times the bitrate of DVD's but is pushing 6 times the resolution therefore to have the same compression as DVD's wouldn't the movie need to be encoded at 30mbps. I don't see how Mpeg 2 could look its best at 18mbps.
What is the bitrate usually of HD-DVD'S VC1 encoding and also Mpeg 4 Blu-ray movies?
11-22-2006 11:55 AM #2
The IPB keyframes which MPEG uses means that the quality to bit-rate ratio isn't 1:1. You could double or triple the bitrate on the same source and it would still fall victim to artifacts. It's more about HOW it's encoded, not at what rate. I would think that studios would use a multi-pass variable bit-rate encoding to get the quality at a certain level for VC-1/MPEG-4.
11-26-2006 05:06 PM #3
11-27-2006 08:34 AM #4