Talk:Variable bitrate

VBR not supported by hardware is a moot point

Perpetuating that VBR is not supported by hardware was a valid point in the 90's. Give examples of modern hardware not supporting it or i shall remove this moot point. --Zaph--213.243.140.48 (talk) 08:41, 2 February 2011 (UTC)

Average bitrate = sound quality?

From the article:

The average of these rates is calculated to produce an average bitrate for the file that will represent its overall sound quality.

Is this true? I would have thought the required ABR for a particular sound quality depends entirely on the content of the stream. (Maximum bitrate, on the other hand...) 129.16.97.227 16:36, 27 August 2007 (UTC)

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Modern disk drives also use VBR recording to allow more sectors to be stored the outer tracks of a hard drive, compared to the inner tracks. This allows more sectors to be written and increased capacity of the drive (the areal density of bits on the platter remains the same, but you can get more sectors on the outer tracks of the drive when compared to the inner tracks. 209.214.214.3 19:49, 24 April 2007 (UTC)

This isn't really the same sort of variable bitrate that the article talks about. When you do lossy compression (MP3, OGG Vorbis, AAC, etc.) you can choose the bit rate of the _CODEC_ rather than the bit rate of the underlying storage media. The technical issues with variable areal density and with variable bit rate CODECs are very, very different, so they really belong in different articles, IMHO.

Bhimaji 19:02, 27 April 2007 (UTC)

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OGG Vorbis Files are _NOT_ inherently VBR. They can be encoded as CBR aswell. (doesn't make much sense but they can be encoded as CBR)

I'd like some guidance on whether to choose variable bit rate when copying music to my MP3 player. What are the plusses and minusses?

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The phrasing that Ogg Vorbis files can optionally be coded as VBR is like saying MP3 can optionally be encoded CBR. All Ogg Vorbis encoders I'm aware of encode using VBR by default. Also, Ogg Vorbis files are as much inherently VBR as possible. A CBR Ogg Vorbis file is merely one where all the frames have been forced to have the same bitrate.

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I was thinking about if vbr makes harder or even imposible to detect or recover file errors? If I change one bit in a cbr coded audio/video file then there happens nothing except maybe some glitches, but what if it happens in a vbr ecoded?

An MP3 files is made up of a series of independent blocks of data called frames. Each frame has it's own independant header which describes the vital encoding parameters. The reason this is done is so that when streaming something like an online radio station is streamed constantly, you can jump into the stream at anytime and be able to listen. Obviously if all the encoding information was only at the start of the file you would have a problem. The upshot is that regardless of whether an MP3 is CBR or VBR, if any header data is mangled it will only damage at most one frame of data. So no, unless I'm missing something you should not have any more trouble recovering VBR data then you would CBR data.

amRadioHed 03:46, 17 March 2007 (UTC)

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Information on the quality settings for variable bit rate would be helpful too. My understanding is that a quality setting of VB_0 is higher than VB_9, but I have no clue why that is.

--17:01, 23 October 2006 (UTC) user:lenehey

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Could someone knowledgeable add info about VBR Video playback and encoding? PipOC 23:40, 1 January 2007 (UTC)

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Does anyone else remember that it was Xing who first wrote the VBR extension for MP3 in their encoder? Is VBR part of the MPEG Layer 3 ISO specification? 71.162.255.53 23:25, 29 June 2007 (UTC)

Pros and Cons

I have a problem with the wording of this sentence: "Devices that support only CBR encoded files are becoming increasingly difficult to find." Why would you want to look for them? Furthermore, this section should be renamed because it doesn't really have any cons. --194.251.240.114 02:42, 5 February 2007 (UTC)

Many thanks to those who expanded upon my original musings in this "Pros & Cons" section (now Advantages and disadvantages), which were based on experimentation with CVBR back in Jan 2008 (in edits made as 83.67.145.51). In particular, thanks for the part about "fixed quality" encoding - which I can confirm from later experimentation to be a "more ideal" form of encoding now that constraints on storage size are of less importance. I also greatly appreciate the way that discussions on multi- and single-pass encoding, fixed quality, etc, have all got their own sections full of valuable info. This article is now becoming very broad and very enlightening and I look forward to the many more additions likely to be made in the next two year interval! As it is my Birthday, I shall consider this as my Birthday present. Thanks again: this is what Wiki is all about! I'm sure all the many contributors of this Wiki page since back in October 2002 would agree. --83.67.145.51 (talk) 21:18, 27 December 2009 (UTC)...

Thank you !!

about bandwidth

is bandwidth constant in a network ? —Preceding unsigned comment added by 210.212.230.129 (talk) 09:33, 6 January 2011 (UTC)

Far fetched

To me it seems extremeley far-fetched that the VBR pattern may reveal the contents of what is spoken. Should unserious speculations be included in a Wikipedia lemma? Yes, I am aware that it is supported by a reference - but that does not say a lot to me! 81.207.20.42 (talk) 08:08, 23 April 2014 (UTC)

Having read a paper on this before in connection with Opus (audio format), I'm convinced that the data provided is plausible in demonstrating that key spoken phrases that are rare enough may be statistically inferred from bitrate variations (in certain codecs at least). This may allow interested parties to focus brute-force decryption efforts on the most likely candidates, improving overall detection rates.Dynamicimanyd (talk) 19:56, 22 May 2015 (UTC)

TVBR

What does TVBR stand for?--2A02:810A:11BF:E564:5AB:D9E:57E8:EF6D (talk) 20:39, 28 January 2021 (UTC)

[...] or white noise will require a higher bit rate to encode without visible artifacts

Possibly outdated, as modern video codecs allow cheap signalling of white noise using noise modelling. 46.230.131.152 (talk) 10:42, 16 February 2021 (UTC)