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  1. Member
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    In making DVDs for home theater players, over the last year I thought I had the right "best practices" in doing the process..... I have since met-up online and chatted with a professional that writes for a digital video magazine... I'm not including his name because I dont have his permission, but here is what he recently taught me:

    " You have to be very careful about bitrate. the DVD standard allows for a bitrate of up to 9.mbps but there is not a DVD player on the market that can reliably and effectively playback a DVD at this rate. Frankly anything above 7.8mbps is almost guaranteed to not work on 2 out 6 DVD players. Then you also can have issues with VBR which some players do not like either especially at higher bitrates.

    Welcome to the highly problematic world of DVD burning.

    If you want to make a DVD that is as safe a bet as possible to play or all DVD players (as much as that is ever possible , it can never be guaranteed) Then 6-7mbps CBR is the sweet spot. Anything more can be problematic. You really dont trade off all that much visible quality between 6 and 8mbps but certainly I would Not encode at 9mbps.

    Regarding the Advanced tab in Vegas7 under the MainConcept MPEG2 format. When making a DVD.....NEVER touch it...! Remember the Mpeg format, whilst the standard for DVD is actually used for countless other means other than DVD and was never made specifically for DVD. So the DVD format demands a specific set of Mpeg2 parameters. if you were making Mpeg2 for a non-dvd playback you could tweak all sorts of things but the DVD player is very fussy and thats why the templates are there. other than bitrate always leave the template Mpeg2 settings as they are or you're just asking for trouble."


    Just though I'd pass it along if it would help anyone.
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  2. Member Cornucopia's Avatar
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    We recently had a discussion on this topic in this thread: https://forum.videohelp.com/viewtopic.php?t=324929, and the result was "disputed" to say the least.

    If this guy is the AUTHORITY that you say he is, have him post on this site, we'd welcome it.
    But "authority" or not, he'll need conclusive, concrete and objective evidence to back up his claims--which I don't think he has yet. Both the prosumer and the professional communities often operate on shared assumptions and "rules-of-thumb", some of which become antiquated or outdated. Yet they are still promulgated as the divine truth.

    I'm doing my part in doing some actual testing to get to the bottom of this "accetable max bitrate" question. What about you?

    Scott
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  3. Member
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    The usual sort of mi-informed rubbish masquerading as fact spouted by lots of self appointed 'experts'. A professional who writes for a magazine is a bit like a teacher. As they say about teachers, those that can do, those that can't, teach.

    They conform to the normal definition of expert, ex - former or has been, spert(spurt) - a drip under pressure......
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  4. Hi Cornucopia,

    I removed my post, not realizing you had posted already. I decided he might be talking about CBR encoding mostly, after originally figuring he was discussing VBR encoding, with max bitrates in the ranges he was mentioning. If it's VBR encoding with max bitrates, I think he's wrong on most of his points. But deciding that I had no first hand evidence on how players react to CBR encoding in the high ranges he's discussing, I decided to delete my post.
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  5. Member Cornucopia's Avatar
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    RichardG, that's a little bit harsh; I certainly wouldn't dismiss the whole profession like that. There are many VERY knowledgeable technical writers out there. Jim Taylor is a great one.

    This man in black could very well be telling what (s)he has exerienced to be true and spouting the hollywood/pro community company line as words of wisdom to whom (s)he may consider to be a fledgling. But nobody can make statements like that without evidence, is all I said. I know there certainly hasn't been any public report(s) made about this topic.

    No need to bash somebody's credentials. (Just yet-- )

    Scott
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    What a crock...

    Let's review how a DVD is read by a player (and, by this, I mean any player). All DVDs are read by the player at a constant rate of 26.16 Mbps. After a 16/8 decoding, this results in a data bitrate of 13.08 Mbps. Subtract 2 Mbps of error correction, and 1 Mbps of navigational overhead and you have a data stream that YOU can use of 10.08 Mbps. Of this 10.08 Mbps, the MAX that can be video is 9.8 Mbps (by specification). Therefore, whether you have a DVD that is encoded at 2.8 Mbps or have a Superbit DVD, it is read by the player at a constant rate of 26.18 Mbps.

    Now some machines may have issues performing error corrections for high bitrate DVDs that have many errors (such as DVD+/-Rs), since this correction can be CPU intensive. This would imply that Mr. "Anonymous" is having disc blank quality issues (which we are all aware of here). But for a commercially pressed DVD, these errors are relatively low, so virtually all players can perform any needed error corrections at full speed.

    This thread reminds me of an old joke. "What's the difference between a used car salesman and a computer magazine writer?" ANS: The used car salesman knows that he is lying to you.

    Yeah, I'll reaffirm here... What a crock. No wonder this guy wants to remain "anonymous".
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  7. Member thecoalman's Avatar
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    Just my .02 but I see little benefit in going over 8000 to begin with, in most cases 6000 is more than sufficient and considering disc capacity limitations as far as I'm concerned it's a moot point.


    Originally Posted by Richard_G
    As they say about teachers, those that can do, those that can't, teach.
    Funny how kids spend 4 years in college learning a profession then spend the next 4 or 5 years unlearning it. :P
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    Originally Posted by thecoalman
    Just my .02 but I see little benefit in going over 8000 to begin with, in most cases 6000 is more than sufficient and considering disc capacity limitations as far as I'm concerned it's a moot point.
    But these are your preferences. What if your preference was to max out your bitrate at 9.8Mbps? This guy has just told you that your preferences are not valid.
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  9. Member oldandinthe way's Avatar
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    He didn't say your preferences were not valid, he said your preferences could be problematic.

    Often the case is, that when you operate at the extremes of a specification which allows sufficient variability you experience a greater number of problems - or at least risk experiencing a greater number of problems.

    There are sufficient areas in which the DVD spec is loose to believe this is so and that there is a "sweet spot". Some of you point to blank media problems, as a potential cause for the "experts" experience.

    As you know, some of us feel that given the nature of the DVD specs and certification what you call blank media problems can be attributed to the DVD burner. And that it is the responsibility of the burner under to the specs to adapt to the media. The fact that there are burners which for the most part succeed at this, is offered as evidence.

    Accomodations to the vagaries of the spec are commonplace. All of you folks who burn DVD-R for compatibility reasons or set the booktype on DVD+R are performing exactly that.

    I don't know if the expert is right or wrong. But in this case it doesn't set off my "bullshit detector".

    When specs are a loose as the DVD specs are users run into varying results. The interpretation of those results, and methods of avoiding the problems are matters of experience and opinion. There will never be unanimity as to were the fault lies, and what the best means of avoiding the problem are.
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  10. There must be some substance to what this guy is saying, just check the bitrate of commercial DVDs, it hovers between 6 to 8 Mbps (including Superbit). I'm not saying no discs go over that, I have seen some very short spikes go higher, but that's all they are, spikes. Unless you encode a disc at 9Mbps CBR, using VBR nobody can claim the material is all encoded at 9Mbps. So, in the end what percentage of a 9Mbps VBR disc is actually 9Mbps? What's the average bitrate, 6 to 8?
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  11. Member adam's Avatar
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    The guy is mostly just being highly conservative in his suggested settings. Considering the audience of his publication I don't think its an unreasonable suggestion. But SLK001 nailed it on the head. The problems he refers to have nothing to do with high bitrate or VBR vs. CBR per se, but everything to do with media compatibility with hardware players.
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  12. Video Restorer lordsmurf's Avatar
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    Originally Posted by Richard_G
    The usual sort of mi-informed rubbish masquerading as fact spouted by lots of self appointed 'experts'. A professional who writes for a magazine is a bit like a teacher. As they say about teachers, those that can do, those that can't, teach.
    They conform to the normal definition of expert, ex - former or has been, spert(spurt) - a drip under pressure......
    Those that teach "do", those that can't "just write articles".

    You can come up with all kind of cutesy sayings, but it really just depends on the person.

    The assurance that "no player can play 9mb/s" (paraphased) would be revealed as bullshit quite easily. He need only to come to my house and use a Toshiba 2800 or JVC DR-M100S. I know for a fact that those will work beautifully with CBR 9.8mb/s MPEG-2 DVD streams and not even blink. I'm sure there are many, many more.

    Sounds like somebody needs to quit buying the $20 Chinese Wal-mart special. When it comes to those cheap machines, bitrate is the least of your problems.
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  13. Member adam's Avatar
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    nic2k4: 9MB CBR is not used for practical reasons. Even with only one audio track you'd be limited to little more than 90 mins on a dual layer disc. For virtually any source you are also going to reach the point of diminishing returns at a lower bitrate too. But a commercially pressed disc could absolutely store the data at max bitrate throughout. Per the standard, all hardware players are required to be able to play this back. As SLK001 said, data is read off of a DVD at a fixed rate of speed and stored in a buffer. It literally makes no difference what the bitrate of the data is on a pressed disc, so long as it is within the standard.

    But burnt media is not as compatible as pressed media, so results vary.
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  14. Member
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    Hmmmmmmm...
    I'm going to think up a Cutsey Saying
    Bitrate too High - DVD will die
    Bitrate too low - Quality will Blow
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    <decided to remove>
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  16. Always Watching guns1inger's Avatar
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    You are putting one man's conservative, and I would say outdated' opinions against the combined experience of thousands of hours of practical authoring experience across a very wide range of software, burning hardware, media and playback hardware. Yes, it's all opinion. But when an opinion can be so easily refuted by facts, you have to question it's worth.

    Get your anonymous magazine author to come and post here. The more professionals, the better. He can put his credentials, experience, and supporting data to the forum.
    Read my blog here.
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  17. Member Cornucopia's Avatar
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    ...I'm beginning to lose interest. :yawn:

    This is starting to look like a new flame-bait troll on the boards...

    jimcornetet, what "help" have you asked for that you didn't get? How to copy-protect? Got your answer ("No, can't!"). It happens to be an answer you don't like, but it still is helpful to know. Do you really want help?
    This here thread isn't even a request for help, it's a "My big brother told you so" thread. All we're saying is, "OK, put up or shut up".
    I've been proven wrong on this forum before and have apologized and learned new stuff. I have also set a number of people straight, against many odds--WITH INCONTREVERTABLE PROOF. It goes both ways.
    How are you helping somebody with your ALL-RED-LETTER (like you're the word of GOD or something) posturings?

    We want to help. We want newbies who'll accept our help and become a helper also, not constantly challenge...

    cue---(MontyPython): "I'd like to have an arguement, please."

    Scott
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  18. It's getting hit on the head lessons in here.
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  19. Disgustipated TooLFooL's Avatar
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    y'know guys, i see the OP's point... on his last thread, true he was not happy with the answer, but he was quickly questioned and attacked about his right to produce dvd's of a school play. when he responded with HIS credentials, and the budget that went into the production, everyone put thier foot in thier mouth and went back to the original subject. now that you know the kind of work he is involved in, don't you think it's possible he has spoken to some else who may know what they're talking about? why do we need to suddenly question who he spoke to? he is simply sharing something he learned.
    I am just a worthless liar,
    I am just an imbecil
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  20. Member
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    ToolFool.... if you were a woman I'd kiss you on the LIPS.

    someone understand me as a newbie.

    holy shit
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  21. Banned
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    Just because some manufacturers make CRAPPY players incapable of utilizing full potential on any given format, it does NOT make such format's settings - that are still withing format's standard - "invalid" or "problematic".

    I remember one of the early iPODs brochures I got at some show. It said in capital letters: "ipod - The only player you'll ever need" (or so). That thing didnt play anything else but its own proprietary format plus mp3, no ogg, no wav, no ... , yet it was "the only player I'll ever need"
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