VBR versus CBR?
Frage von JMS Productions:
Hello community,
I dig me now for days by Google and try the qualitative difference between VBR and CBR and find out.
A little wiser, I have become. For the whole various internet sources, I am now to the following conclusion:
VBR is better quality than CBR ...
Whether this is true, I do not know and I would now like to ask here. I understand in principle, not yet, when it is appropriate to use CBR and VBR time. I am holding, actually that CBR should be better, because I can, for example, a constant bitrate of 7300 kbit / s Setting and know that my film ALWAYS with 7300 kbit / s is played. With VBR, the whole thing quite so volatile. Then times only 2000 kbit / s and then played 8000 times kbit / s? These violent fluctuations in quality but then you would have seen, does not it?
Another small problem:
I have EncoreDVD with a movie with menu and Pi Pa Po created. Everything OK. Now the film is, unfortunately, but ~ 75 minutes, which is now means that the next bit rate must be down, otherwise it does not fit on a normal 4.5 GB DVD. For a constant bit rate should I at 7300 kbit / s go down, it fits the film just as on DVD. (There are probably still 20-30 MB free.) So the brim burned. But the quality convinced me s.manchen agencies still can not really and I can increase the video bit rate is no longer, because otherwise I have the audio bit rate reduction would have profound and I would not. (Currently this is at 192 kBit / s)
Now it was time somewhere, VBR would be in such a case better quality. Well, but now someone I can say what I do as a minimum bit rate, and as a target Birate Max bitrate in this case should be set? As I said at a constant bit rate was not higher than the 7300 kbit / s, otherwise the film does not fit on DVD. So may be synonymous with this Variable Bitrate 7300 kbit / s is not exceeded? Do I need this value then as Max bitrate take? And how far should I set the minimum bitrate? In 1500 Encore is set by default. That would be me now too low. I would have something with 6500 kbit / s taken as the minimum, target bitrate: ~ 7000 kbit / s and maximum: 7300 kbit / s (because it no longer fits, according to CBR). But thus resembles the whole thing again almost a constant bit rate, up to small deviations ... This is quite confusing!
Maybe could you kindly provided me the difference of CBR and VBR explain and especially WHEN I should use what and why seems VBR is better than CBR ...
Vielen lieben Dank!
Antwort von Markus73:
Then times only 2000 kbit / s and then played 8000 times kbit / s? These violent fluctuations in quality but then you would have seen, does not it? Not necessarily, because the bitrate is not changed arbitrarily, but that happens as a function of imagery. In short, s.Stellen, where it is needed (Bildhinhalt complex, lots of change) is a higher bitrate is used. Where this is not the case, will also work with a lower rate.
VBR is in any case, the smarter alternative, especially if you on the venue, or the file size must respect.
My experience is that I am at my software (Magix VdL pretty good with the MainConcept encoder) be the minimum to 4000 kbit / s can be set without the annoying feeling.
Regards,
Markus
Antwort von JMS Productions:
My experience is that I am at my software (Magix VdL pretty good with the MainConcept encoder) be the minimum to 4000 kbit / s can be set without the annoying feeling. Yes, I use MAGIX synonymous rather than Premiere, the problem is that obviously not MAGIX s.die DVD menu comes, for example, has the EncoreDVD. Therefore, I must always s.Schluss the film from Magix EncoreDVD in export and import ...
VBR is in any case, the smarter alternative ... And how should I now set the values? As I said, if I use CBR, it is at 7300 kbit / s conclusions. More does not fit on it. How does the whole thing then VBR from? There are minimum bitrate, target bitrate and maximum bitrate. What values should I use for the 3 to adjust the quality as good as possible style? I mean, what do I mean when I, as a minimum bitrate 1300 kbit / s suppose, or 7000 kbit / s? Can I use the maximum bit rate as high as possible? There must be differences, right?
Thank you in advance for the help ...
Antwort von B.DeKid:
Hi
With VBR, you can at certain "images" better results.
Or. The file is smaller than s.Schluss with CBR
Example:
You have a moving picture to represent this with no errors, the bit rate very high. (Children playing football in the park with moving people / trees in the background)
You do not have a moving picture, it can lower the bitrate of course be set. (Landscape with no real movement of the background.)
....................
The VBR setting can save just MB, but it may be harder to calculate. But quality is better.
The CBR takes no preference as the Picture of always looks the same bitrate.
As for the calculation of file sizes simplified. Qualification for certain images may be worse.
....................
What values you enter now will only run of the film (picture sequences) from. (Of course, synonymous with the medium on the output.)
The 3 settings refer thus to
Lowest Bit Rate (Picture without movement)
Standard Bit Rate (Average movements in the Picture)
Highest bit rate (fast movements in the Picture)
.........................
If CBR 7200 final, then it's time VBR as follows
5000
6500
8000
But as I said these settings vary depending on the material.
MfG
B. DeKid
PS. For DVD s Max bitrate may not be over 10 000 as far as I know, because otherwise the DVD player does not come with clear.
................
Note
http://de.wikipedia.org/wiki/DVD (look at speed because of what is
The default data rate is 1x for DVDs at speeds of 1.35 MB / s. and 10.8 Mbit / s whether this is just to read or describe the impact I can not tell you.
And here again is http://en.wikipedia.org/wiki/Variable_bitrate everything regarding VBR
.............
Note 2
Hab mal compatriots whether there are bit calculator, I found here http://www.videohelp.com/calc.htm can calculate synonymous VBR.
Even for different DVD s. (Java must be installed, has degrees lasted about 2 minutes until the downloaded and installed, so not an issue.
`` I think it would be better if the tool then the film once scanned so as to see what bit rate than maximum use was. Na Yes you can not have everything ;-)``
Antwort von jazzy_d:
Make a folder on hard disk with CBR with max. Data rate for 8.5GB DL. Then you take any DVDschrumpf and steaming it exactly 4.7GB one. Then you take a decent Brennproggi rand and do a full 4.7GB DVD with the best quality to go.
Antwort von tommyb:
Generally you should make sure that your DVD will be completely filled.
CBR With self-burned DVDs is the overall limit for the data somewhere in 8000kbit / s (including all soundtracks). That is, if your sound with 192kbit / s encrypted, remains just 7808kbit / s left for video. I would be somewhat lower since starting, ie the maximum 7500kbit / s.
According bitrate calculator to fit 7500kbit (+192 for audio!) About 1 hour and 20 minutes on a DVD5 disc.
If your video no longer than 1:20, then you should choose CBR at a bitrate of 7500 (+192).
VBR - One Pass (Quality) If you want maximum quality and bitrate so much want to save as possible (whether it is to accommodate the extras are not as important as the main movie), then take the One Pass VBR procedures. Because do you a minimum and a highest bit rate.
Moreover - and this is the Cinema Craft Encoder so - you define the "Quantization Factor." This determines how much of the encoder's bit rate can put down. The higher the number, the more likely the codec can reduce its bitrate. This leads to high numbers of extremely poor quality, too small, the potential savings barely exists and VBR mode, this is not necessary.
Values between 10 and 20 are ok.
The lowest you can synonymous 0. After all, why should the codec 2000kbit / s for wasting a black picture? He will never arrive at 0, but maybe he compresses 10 seconds long black screen with 10kbit / s and you save 2.5 MB s.Space.
At the highest value should be a maximum of 7500 are again. Depending on the Q-factor of the encoder is more or less tend to the highest value.
A major disadvantage of this approach is that the file size never seen before can be, let alone calculated.
VBR - Two Pass (bitrate) This is very efficient. Here you have to take the factor "Q" an average, standard bit rate. This is the reference rate for the encoder and it will s.Ende all Encodierungsprozesses exactly this bitrate meet.
Calculates the bitrate with a bitrate calculator, so you can DVD's - if it has excess length - just as high quality as in the One Pass VBR to grab the DVD and the file size according to meet.
If the encoder is coded, it saves s.weniger complex s.Bitrate points, which he in turn s.den very serious points verballert. But it is the balance so that none of the "bitrates" and always outweigh the average bitrate rauskommt.
The only disadvantage of this process is that at least two passes must be made at encoding. The first pass analyzes the video and the easy / difficult points are noted. The second passage is finally Bitrate efficiently distributed.
Antwort von tommyb:
any DVDschrumpf and steaming it exactly on a 4.7GB About the absurdity of a new coding of video material should I not speak, right?
Antwort von jazzy_d:
It is not new encoded. Is and remains everything mpeg2. The DVD looks "man" no one (1) data reduction. I've Ben Hur on a 4.7 DVD s.normalem TV in perfect quality on my 83cm HDready with credible Zoom1 (4:3 Landscape at full Breitblid).
Antwort von JMS Productions:
Wow, really many thanks for all the useful and above all detailed answers. Nevertheless, I still have a few questions:
According bitrate calculator to fit 7500kbit (+192 for audio!) About 1 hour and 20 minutes on a DVD5 disc.
If your video no longer than 1:20, then you should choose CBR at a bitrate of 7500 (+192). Yes and here, I believe, is precisely the rub, which I apparently still not quite understand:
And now if my video is 1:30 long, then why do I not CBR at a bit rate of my 7200 (+192)?
And if my video is 2:00 long, then why do I not CBR at a bitrate of 6000 (+192)? Is there a kind of border, s.wann I suppose CBR and VBR s.wann I suppose?
If I use VBR:
Is there not some program as it is synonymous B. DeKid would wish that the film just completely "durchscannt" (synonymous halt if it takes longer) and then to decide how high the minimum bit rate, target and maximum bitrate to be . Because where do I even know because of how deep I the minimum-and how high the maximum bit rate set to be / should be. Do I have to because values are based on experience? Sure, a bitrate calculator tells me that, but knows how this how my footage looks like? Whether this is now very blurred or is synonymous with peaceful scenes?
I would, for example, the minimum bit rate (as a quality fanatic) never lower than 6000 kbit / s to actually even higher. Simply everything as high as possible, in order to conclude the best possible quality rauskommt ... However, if minimum, target and maximum bitrate all synonymous as high as possible, then the whole thing is so handy again CBR and what I then used VBR? Actually nothing ...
Liebe Grüße
Antwort von B.DeKid:
Gude
Analysis of the video makes for example. DVD Shrink yes. See jazzy_d's proposal.
To do this but the film already "ready" to be.
What I / We wish us then yes, yes you need in the editing program to be done.
Say the progi scanned the timeline.
I remember which one but if the attitude
5000
6500
8000
take on the page is secure.
But how tommyb said, is the calculation of VBR is not possible.
I would just try to look at whether quality VBR real advantage in your case. Ansonten permanent halt at CBR, I think that nobody really notices a difference.
MfG
B. DeKid
VBR 2Pass is always better, because yes the video will go through 2x.
Antwort von tommyb:
why do I not CBR at a bitrate of 6000 (+192)? Quite simply:
If there are points in your video, there are less than 6000 kbit need, then you wasting bitrate.
If there are places in the video indicates the need more than 6000, then the video is unnecessarily ugly (more or less visible).
That's why we recommend 2pass VBR, if you do not come off s.die 7500. 7200 in the CBR is still synonymous, but only if you want to save time;)
