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Shouldn't there be a 288kbps bitrate
Jojo
post Dec 17 2004, 17:19
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I wonder why there isn't a 288kbps bitrate. There is just 256kbps and after that 320 kbps...I think this gap is quite big. Isn't that a waste of bits? I mean, let's say in a vbr mode, the encoder 'guesses' that it needs 270 kbps there is no way to use 256kbps and the reservoir to compensate the missing bits...so the encoder would have to use 320 kbps...but then, there is no way to store that many extra bits in the reservoir for the next frame.

Same thing for CBR modes. When mp3 was developed most people used CBR since no one could have guessed about LAME's 3.96.1 excellents --preset standard mode. And it's quite a size difference if I use CBR 256 or 320 kbps...especially back then... unsure.gif

This post has been edited by Jojo: Dec 17 2004, 17:21


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Gabriel
post Dec 17 2004, 19:57
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QUOTE
I mean, let's say in a vbr mode, the encoder 'guesses' that it needs 270 kbps there is no way to use 256kbps and the reservoir to compensate the missing bits...so the encoder would have to use 320 kbps...but then, there is no way to store that many extra bits in the reservoir for the next frame.

Well, those extra bits will perfectly fit into the bit reservoir.

As Roberto explained, this is a limitation that comes from the bitrate index in the raw mp3 stream.

I think that Layer III inside mp4 container doesn't have this limitation.
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