How do I tell DVD bitrate?

[hiimbored]

Hi, when I am backing up my DVDs, I would like to able to tell the video bitrate. I use DVD Rebuilder with CCE (set to 6 passes), and after the "preparation" phase, it will say something like this: "HIGH/LOW/TYPICAL Bitrates: 4,935/1,115/4,279 Kbs." I always thought that this meant that 4,279 kbps was the average bitrate, but I've recently been told I was wrong. So what is the correct method of telling average DVD bitrate? Thanks!

[jman98]

If 4935 isn't your maximum bit rate, 1115 your minimum and 4279 your average in this example, I'd also like to see an explanation of what that means. Since I did not write DVD Rebuilder, I can't say for certainty that that's what it means, but it sure seems logical to me that 4279 is your average.

Do you really trust your source that says you are wrong? A lot of people talk definitively about stuff they know nothing about out. We get posts all the time from people whose friends tell them all kinds of incorrect nonsense and the teller insists that what they said is correct.

[manono]

If 4935 isn't your maximum bit rate, 1115 your minimum and 4279 your average in this example, I'd also like to see an explanation of what that means. Since I did not write DVD Rebuilder, I can't say for certainty that that's what it means, but it sure seems logical to me that 4279 is your average.

It might seem logical, but if you bet money on it you'd lose:

Q13. When I'm encoding NTSC non-telecined source, the bitrate seems to be less than when I do the same source using another package. I'm obsessed with bitrates. Why is DVD-RB's lower?

A13. This can get complicated but here goes... DVD-RB is the only encoder-based method I know of that supports hybrid NTSC sources (alternating between telecined and regular video). A part of the way it does that is by setting a common denominator as the framerate at 23.976fps. No frames are lost -- only the rate is changed. When encoding is complete, the framerate is returned to its original state during REBUILD. One offshoot of that is that when encoding the framerate must be adjusted by a factor of .80 (29.97 divided by 23.976) -- so that it hits its target when the framerate changes back (1.25 times the encoded bitrate). The bottom line is that the true bitrate you are achieving is 125% of what you see in the ECL files.

http://forum.doom9.org/showthread.php?p=663398#post663398

[jman98]

Thanks for the explanation manono.

[tinker]

I am not sure how accurate is this one, but worth to check.

http://www.tecoltd.com/bitratev.htm