Does only DVD+R support Variable Bitrate?

[Oegema]

I ve read in several places that DVD+R supports variable bitrate due to the burning method.
Does that mean that DVD-R doesnt and that people with DVD-R burners only can burn constant bitrate DVDs?

[bugster]

I ve read in several places that DVD+R supports variable bitrate due to the burning method.
Does that mean that DVD-R doesnt and that people with DVD-R burners only can burn constant bitrate DVDs?

No, DVD-R(W) DOES support VBR.

[Jester700]

Standalone set-top recorders are different than PC drives. With the set tops, DVD-R only recorded at CBR, where DVD+R can do VBR. Both formats' PC drives will burn VBR files.

[Oegema]

Thanx alot.

Marry christmas to all of you!!

[wizzy]

what are the difrents between CBR and VBR?
what is the best ?

[BJ_M]

Standalone set-top recorders are different than PC drives. With the set tops, DVD-R only recorded at CBR, where DVD+R can do VBR. Both formats' PC drives will burn VBR files.

many stand alone recorders/encoders use VBR , in fact some of them use 2 pass VBR like the pioneer 9000 which burns direct on dvd-r in real time ..

several of my hardware mpeg encoders can also do multipass (2) vbr in real time ..

[Cornucopia]

I have a hard time believing that settop DVD Recorders do anything other than CBR, whether +R or -R, seeing as how they are recording in REAL-TIME and don't know what's coming down the pike in terms of content (unless it had a HUGE timedelaying-preread buffer). REAL-TIME singlepass VBR can vary wildly in filesize. Often it is LARGER than CBR files of the same content, and that wouldn't make much sense from an efficient design perspective. These settops want to give the user an idea of how much time is left available for recording, and it wouldn't know that if doing VBR.

Both types of DVD-Recorder settops do allow you to set the bitrate. The +R/RW and the -RW (VRmode) allow for alot of levels, while the -R/RW (Video mode) only does a few.

As previously stated, computer DVD burners will do either CBR and/or VBR, whether +R/RW or -R/RW or RAM.

CBR vs. VBR is another thread.

Suffice to say multipass VBR can give similar quality to CBR, but at much smaller filesizes (comparing VBR max bitrate = CBR bitrate).

[BJ_M]

Cornucopia - sorry you may have a hard time believing it , but just look up the specs ..

my hardware encoder can do 2 pass VBR in real time .. and the pioneer 9000 dvd recorder does VBR in real tiime also -- 32 different settings in fact .

this is not that unusual for high end mpeg equipmnet - but these are not not cheap "home" type products either ..

[Cornucopia]

BJ_M:

I OWN the PVR-9000 and have read the manual and specs. It sure reads like it just does CBR...Adjustable settings of it sure, but not real 2-pass VBR. What page is that on? I'll have to check it out when I go back to work tomorrow.

Which encoder cards are you talking about? I've used Maestro's MPX-3000 and it does great encodes, but it's 2pass VBR does actually take 2 realtime passes to do the job. As in a 2 hour movie will take 4 hours (plus tiny extra for tape to RTZ)

Not trying to flame, just get more info.

Scott

[BJ_M]

i didnt say the pvr 9000 did 2 pass - just VBR ... its listed on the specification sheet and on the pioneere industrial web site .. i think there is a white paper there also about .. it works in single pass vbr and lists this all over its specs .. it can also run in a cbr mode .. btw , i understand there is a firmware upgrade for these (2 upgrades i believe) ..

pioneer had a lot of problems with this encoder when first released - i hope its better now ..

the Sonic SD-1000 and SD-2000 Encoder do 2 pass VBR (and even 3 pass) (with re-pass of tape on second pass) or bit only VBR single pass or CBR also .. Zapex's encoder 200/300 series does single VBR wit a dual stage (buffer) type dual pass with automatic I frmae and chapter insertion and output to VOb's direct .. Astarte's encoder does also 2 pass but since apple bought this company (yes another company bits the dust with an apple takeover) and shut off production of this really good encoder -- it is no longer considered...

AVID and velocity(HD) both use the real time (hardware accelerated in velocity case - not sure about AVID) Ligos software encoder .. yes it works in real time with single pass vbr and just slightly longer for 2 pass (i have the HD version) .. the Tandburb 5720 does VBR real time ..
the Sony Vizaro has both single and 2 pass ..

yes i use also the MPX-3000 with the DVCE Advanced Encoder Pack option and Maestro, 2 or 3 pass as mentioned..

Digital Vision equipment is considered about the best and you certainly have to pay for it , but several of their products have real time 2 pass with scene detection, real time pan and scan, scratch removal, color correction, aspect ratio change, filtering etc all in real time .. of course their systems all cost over 100grand ..

other encoders - Minerva (2 pass) , Optibase 1 pass vbr (i have one of these also) ..
some others also plus the HD encoders we use .. it is true that there is 2 types of "real time" vbr of whats called 2 pass or more , one type is just using look ahead and predective scene analysis and doesnt of course read the whole film - the other type which i have talked about several times before on this forum uses multiple tape passes and is one of the more comon methods used in 'hollywood" ..

[BJ_M]

Suffice to say multipass VBR can give similar quality to CBR, but at much smaller filesizes (comparing VBR max bitrate = CBR bitrate).

so very true .. but when max file size doesnt mater , the debate is still open (there was a mega thread over this topic) and i'm not starting it again ..

[Cornucopia]

BJ_M--

That was about what I thought (revised). I did check the PVR-9000 manual (haven't yet looked at those websites) and it has only 1 small mention on p.39, and the context on the page has me to believe that it refers only to recording in VR mode. I can now see that it might be that way for both modes, however it obviously seems like 1 pass. But other info on that and other pages also show that the recorder has a 30 second buffer, like I was presupposing as a condition for any type of Realtime VBR.

BTW-have not had ANY problems with this recorder since bought in April--either before or after the 4xmedia-related firmware upgrade. It's a great box!

The bit I said about 1pass Realtime VBR being unpredictable and possibly/probably larger filesize is right out of the MPX-3000 manual, I didn't just pull that out of my A$$.

Those hardware encoders you mention are all pretty decent, sound like you've had some fun with em. Heard amazing things about the Vizaro.

If you have any specs or mans on those babies, I'd love to get a look at them. Let me know if there are any pdfs that you are at liberty to forward, i.e. legally, contractually and ethically.

What I was having a hard time with was not so much 2-pass VBR on encoders (especially tape replay 2pass), but more REALTIME VBR on SETTOP industrial/consumer recorders. 'Course I've already learned more than I knew, but I still don't see those units as incorporating that feature without the large buffer. That's one reason to suppose that the PVR-9000 has great quality and also costs so much more--a pre-encode buffer of that size (30sec) would take up 20MB for YUV or 30MB for RGB. I certainly wouldn't see most consumer stuff being outfitted like that.

Well, this has certainly been a refreshing and informative discourse!!

Thanks,

Scott

[BJ_M]

Cornucopia - i am really interisted to hear that the 9000 works so well , i had heard a few bad things about it early on and i havnt heard from to many people who accually used one (you know how rumours go) .. that stand alone encoder has a lot of nice features for the money and you can buy them today for around $1800 , having componet inputs is the real bonus .. as well as reported excellent quality -- compare this to the $20,000 on up encoders (like way on up) ..

on the manuals , well .. i have all the spruce, sonic, optibase and dps and avid and several others -- but been very cautious about ever letting copies out as i know in some cases (spruce and sonic (as well as shake, fusion and others)) there would be a major demand for a copy (based on the number of "users" of maestro and scenarist i see on this forum ), plus in some cases its just simply a mountain of binders and books and such.
i'll see what i can work out ..

[Cornucopia]

2 things:

the PVR-9000 has composite, svideo, and dv in-and-out, but only OUT for the component/RGB. (could be wrong-this is from memory at home now!?!?)

don't worry about the mans for now. i was just fishing for new and or interesting tech info. I've already got canopus and spruce manuals, and as you said many of those and others-sonic/daikin, etc. are target web items. i don't need them for the how to info. I was thinking more stuff on what xyz does with the closed-captioning stream, or recommendations of matrix values for certain program content types, etc. What I probably actually want/need is a "Pro Mid or Master level Encoding" seminar.

Thanks though,

Scott