shithub: sox

--- a/ChangeLog

+++ b/ChangeLog

@@ -25,6 +25,11 @@

   -------  ----------------------  ----------------------  -------

   14.4.0   E mixer                 remix                   2013-03-04

+Effects:

+  o 'Deemph' can now also be used at 48kHz sample rate.  (robs)

+  o 'Rate' now much faster in many cases.  (robs)

 Internal improvements:

   o Speed optimization for effects that operate on channels

--- a/sox.1

+++ b/sox.1

@@ -1891,7 +1891,8 @@

.EX

    play track1.wav deemph

.EE

-The de-emphasis filter is implemented as a biquad; its maximum deviation

+The de-emphasis filter is implemented as a biquad and requires the input

+audio sample rate to be either 44.1kHz or 48kHz.  Maximum deviation

 from the ideal response is only 0\*d06dB (up to 20kHz).

.SP

 This effect supports the \fB\-\-plot\fR global option.

@@ -1947,8 +1948,8 @@

 .B \-S

 option selects a slightly `sloped' TPDF, biased towards higher

 frequencies.  It can be used at any sampling rate but below \(~~22k,

-plain TPDF is probably better, and above \(~~ 37k, noise-shaped

-is probably better.

+plain TPDF is probably better, and above \(~~ 37k, noise-shaping

+(if available) is probably better.

.SP

The

 .B \-a

@@ -3971,12 +3972,12 @@

 \fBupsample\fR [\fIfactor\fR]

 Upsample the signal by an integer factor: \fIfactor\fR\-1 zero-value

 samples are inserted between each pair of input samples.  As a result, the

-original spectrum is replicated into the new frequency space (aliasing) and

+original spectrum is replicated into the new frequency space (imaging) and

 attenuated.  This attenuation can be compensated for by adding

 \fBvol \fIfactor\fR after any further processing.  The upsample effect is

 typically used in combination with filtering effects.

.SP

-For a general resampling effect with anti-aliasing, see \fBrate\fR.  See

+For a general resampling effect with anti-imaging, see \fBrate\fR.  See

 also \fBdownsample\fR.

.TP

 \fBvad \fR[\fIoptions\fR]