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Originally Posted by badmonkey /img/forum/go_quote.gif
Not really. Lossless formats are just container formats for the raw WAV, which is obviously CBR.
Of course in reality the number of bits going into the decoder per second varies, but you might as well say that a ZIP'ed Word doc has a VBR.
You might notice that Foobar displays the current but varying bitrate of an MP3 or AAC file when playing. But it displays the average for a FLAC.
Depends how you want to think about it. But the encoding philosophy that is implied by the term "VBR" is unique to lossy formats.
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Well, when I say "lossless" I mean a lossless codec (like Apple Lossless, FLAC, WavPack, ..). Not uncompressed PCM in a WAV or AIFF container.
I am quite sure a lossless codec like FLAC encodes each bit at a variable bitrate (VBR). Where silence get close to 0kbps, and more complex parts get much higher bitrate. Then the average bitrate (file size / playing time) is calculated and displayed to the user.
For me variable bitrate (VBR) mean that the the codec vary the allocated bits for each sample through the file, depending on its complexity. Resulting in a smaller file than using CBR, which have to identical to the most complex sample.
Edit: Or am I totally wrong?
Is its...
CBR (Constant bitrate)? Obviously not, since there are no constant bitrate shared between several files.
ABR (Average bitrate)? I fail to see why, as it target minimum sice, and not a specific targeted one (like ex. MP3 and its 128kbps, 192kbps, which are ABR).
Quote:
Average bit rate can also refer to a form of variable bitrate encoding where the encoder will try to reach a target average bitrate or file size while allowing the bitrate to vary between different parts of the audio or video |
Source:
http://en.wikipedia.org/wiki/Average_bitrate
VBR (Variable bitrate)? Most likely, since thats the most effective way to encode a certain audio data stream to the smallest possible size. Varying allocated bits depending audio sample complexity.