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Commit f7273861 authored by Jean-Marc Valin's avatar Jean-Marc Valin
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ietf doc: folding, VBR, misc

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......@@ -528,6 +528,21 @@ and if a sufficient number of bands have a high enough gain, then the pitch bit
Otherwise, no use of pitch is made.
</t>
<t>
For frequencies above the highest pitch band (~6374 Hz), the prediction is replaced by
spectral folding if and only if the folding bit is set (otherwise, the prediction is simply zero).
The folding prediction uses the quantised spectrum at lower frequencies with a gain that depends
both on the width of the band N and the number of pulses allocated K:
</t>
<t>
g = N / (N + kf * K),
</t>
<t>
where kf = 6.
</t>
</section>
<section anchor="pvq" title="Spherical Vector Quantization">
......@@ -643,7 +658,7 @@ the pitch predictor for the next few frames.
<section anchor="vbr" title="Variable Bitrate (VBR)">
<t>
Each CELT frame can be encoded in a different number of octets, making it possible to vary the bitrate at will. This property can be used to implement source-controlled variable bitrate (VBR).
Each CELT frame can be encoded in a different number of octets, making it possible to vary the bitrate at will. This property can be used to implement source-controlled variable bitrate (VBR). Support for VBR is OPTIONAL for the encoder, but a decoder MUST be prepared to decode a stream that changes its bit-rate dynamically. The method used to vary the bit-rate in VBR mode is left to the implementor, as long as each frame can be decoded by the reference decoder.
</t>
</section>
......@@ -803,12 +818,17 @@ Insert some text here.
-->
<section title="IANA Considerations ">
<t>
This document has no actions for IANA.
</t>
</section>
<section anchor="Acknowledgments" title="Acknowledgments">
<t>
The authors would also like to thank the following members of the
CELT and AVT communities for their input:
The authors would also like to thank the CELT users who contributed source code, feature requests, suggestions or comments.
</t>
</section>
......
#include <string.h>
#include <stdio.h>
int main()
{
int comment = 0;
int col = 0;
char c0, c1;
c0 = getchar();
while (!feof(stdin))
{
c1 = getchar();
if (c1==9)
c1 = 32;
if (col < 71 || c0 == 10) {
putchar(c0);
} else {
if (c1 == 10 || c1 == 13)
{
putchar(c0);
} else {
putchar ('\\');
/*printf ("%d %d %d", col, c0, c1);*/
putchar (10);
putchar (c0);
col=0;
}
}
col++;
if (c0 == 10)
col=0;
c0 = c1;
}
}
\ No newline at end of file
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