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...I'll tell you my story:
So we make encoders like QuEnc etc that try to obey such limits as the VBV/STD buffer. However when an encode is run through apps like bitrateviewer people tell me that the encode has spikes above 9.8MBits/sec. I tell them not to worry as the buffer is obeyed and that's all that matters and ignore their worries. Then I find out that these spikes are causing all manner of problems for DVD Players. So I limit it to the literal 9.8MBits/sec AND obey the buffer limits. Then things appear to be fine.
So this is at least why I do a literal limiting rather than just rely on buffer control.
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Hem, I read something [well, maybe something more than just "something"] about the story, by looking at some posts related to QUEnc development. Some of these posts have not being very nice, to say the thruth, and someones seemed really offensive, so first of all let me state clearily that I fully agree with your reasons and with the way it was decided to implemented the max bitrate constraint in your excellent encoder. That's all. I have to say again that the community (myself included of course) should be grateful for all what you did (and are doing) on the subject.
Said this, I am almost sure that many of the reported troubles were caused by the adoption of authoring applications [that have the responsibility of formatting the assets] that simply did not properly implement the STD buffer constraint. Among these applications there are all the ones based on the code of mplex [ifoedit as example...]. This can be easily demonstrated: there are some profiling tools available to professionals [Mpeg2 TS and DVD-Video veryfiers from Tektronix and Phylips] showing that today as example Scenarist and Muxman are properly handling the STD buffer during the muxing stage, but many other authoring applications are not.
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...sorry but i have to disagree. when a specification GIVES a time period for a maximum bitrate to be averaged over,which the dvd specs do with the /sec, then it is applicable aswell. to simply ignore it is to invite problems which has already been shown.
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OK. It is evident here we are in disagreement.
I can just say that it does not seem to me that specs are stating exactely the time period for the max bitrate to be averaged over. If you could point me out some references, it would be appreciated. I have to say again I read many documents, and everywhere it is stated that the datarate of 9.8 Mbps (for the video) and 10.08 Mbps (including video, all audio, all subpictures), should be sustainded by a standard decoder for an indefinite period of time... My position is that the simple value of the bitrate is not giving any indication about the time over wich the measure is taken...
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would it have been more preferable if i had simply told him to use search and not ask things that have been discussed before ? ...i didnt know that was such a crime.
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Of course you're right... it's not a crime...
I just felt it was maybe not correct just to close in a whimsical manner an argument that is debatable (and maybe it is so debatable that in the past the discussion led to flames)... I's just a personal opinion (so it is maybe not relevant) but maybe some reference to "storic posts" would have been really much more appreciated...
SD