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View Full Version : Quick question about VBR


jubilex
10th April 2007, 21:54
Is the set bitrate the average over the entire film, or per minute, or what?

In other words, could there be a ten-minute scene that averages twice what the VBR is set at as long as some other scenes have much lower than the stated VBR? Or is it like any given minute will not average greater than the VBR?

gameplaya15143
10th April 2007, 23:10
could there be a ten-minute scene that averages twice what the VBR is set at as long as some other scenes have much lower than the stated VBR?That case would be how ABR works (ABR = Average Bit Rate, is a form of VBR), but 10 minutes is a bit much for a single pass ABR encode (the averaging duration is usually shorter than 1 minute)

When talking about 2pass VBR, or single pass quant/quality based encoding, the answer is 'yes' to that situation. 2pass VBR averages across the entire video.

jubilex
10th April 2007, 23:29
Thank you.