DvdRebuilder gives way too low bitrate

[t0tum]

I have this situation right now,
my main movie is 135min, 1 audio stream 448kbit and simple menu (10mb).
After preparation step rb gave me,
- HIGH/LOW/TYPICAL Bitrates: 3.700/2.597/3.228
this came surprising to me, so i calculated the average bitrate myself and found it to be around 4050+kbit.
I know, if i still continue with this project rb will encode it right up to the size.
Ive stripped everything to keep the quality of this backup as high as possible, but 12min cell with average of 2.597 is unacceptable! :scared:

Wouldn't i be better off by creating single .d2v project with an average of 4050kbit and running it manually with cce?

[feedback]

That's wierd. Are you using Pro. version RC4?

Regards,:)

[SpazzHH]

What you are not understanding is that those bitrates are at a frame rate of 23.976. After Rebuild when the flags are set for playback at 29.97, your bitrate rises accordingly.

[jptheripper]

pal or ntsc?

if ntsc i thought jdobbs changed the bitrate calc to be based on 29.97 not 23.976,

and the bitrate has nothing to do with the program, what fits is what fits. it is likely in a 135min movie you will have a 12 minute low action scene that doesnt need more than 2600

[SpazzHH]

pal or ntsc? if ntsc i thought jdobbs changed the bitrate calc to be based on 29.97 not 23.976

Actually, now it shows both.
Modified the display of NTSC bitrates so the actual achieved bitrate (29.97fps) and the ECL file bitrate (23.976fps) are shown. In the past the lower (ECL) rate was displayed and prompted questions as to why it was lower than what might be hand-calculated. The ECL rate is used as part of the method to ensure support for hybrid sources and is readjusted as when necessary during REBUILD.

[feedback]

What is the name of the movie?
Is it ILVU intensive?
HIGH/LOW/TYPICAL Bitrates: 3.700/2.597/3.228 is terrible.

HIGH/LOW/TYPICAL Bitrates: 3,700/2,597/3,228 is not bad.

Decimal point confused me...doesn't really take a lot to do that though. :p

Regards,:)

[jdobbs]

pal or ntsc?

if ntsc i thought jdobbs changed the bitrate calc to be based on 29.97 not 23.976,

and the bitrate has nothing to do with the program, what fits is what fits. it is likely in a 135min movie you will have a 12 minute low action scene that doesnt need more than 2600 The bitrates never actually changed, only the reporting. Because everything NTSC is encoded at a constant 23.976 with Rebuilder (and then converted back during rebuild), a source that was truly 29.97 (not telecined) was being reported at a rate that is 25% less than actual (29.97 / 23.976 = 1.25).

The reason I put it in was for all the people who are hung up on bitrates (which by the way really isn't a good indicator of quality) were complaining because other packages (to be left unnamed) were giving a higher bitrate. That, of course, wasn't true -- they just didn't understand how RB works.

On that subject to those who have that silly bitrate fetish... try encoding a DVD using a poor quality encoder (like ReMPEG2, for example) and you'll see that a high bitrate doesn't relate to high quality -- and that one is an encoder (contrary to what it calls itself), a transcoder uses the available bitrate even less efficiently.

The quality of the encoder engine is what really counts. I'll take CCE at 2500Kbs over transcoded output at 3500kbs any day of the week.

[t0tum]

Tnx for clearing that out for me.
My source was NTSC indeed.

[jptheripper]

hey jdobbs, anythought to an old request of adding the bitrate for each title set to the log? would be nice to see without having to go to rb-opt everytime.

[jdobbs]

Unfortunately it would just be a source for more confusion for most people.

What I'd get is a flood of e-mails asking why "Segment x only had a bitrate of 1200Kbs?".. with the belief that somehow low bitrate is the same as low quality. Of course the answer is "because DVD-RB does an analysis of the original VBR and that segment was very simple video that only needed 1200kbs."

I would hpe that those folks using RB-Opt are smart enough to know that so they don't waste space trying to unnecessarily raise bitrates (which would hurt other parts of the video).