zretune
Section: USER COMMANDS (1)
Updated: Sept 2012
Page Index
NAME
zretune - resample an audio file in order to change its pitch
SYNOPSIS
zretune
[options] input-file output-file
DESCRIPTION
zretune
resamples an audio file by a the inverse of a ratio expressed in cents,
without changing the nominal sample rate. The result is to change the
musical pitch and lenght of the file. Input can be any audio file
readable by the libsndfile library. The output file type is either
WAV, WAVEX, CAF, AIFF or FLAC.
OPTIONS
- --help
-
Display a short help text.
- --cent pitch change in cents
-
The number of cents by which the pitch is changed. The accepted
range is +/- 1200 cents, the useful range in practice will be
something like +/- 100 cents.
Output file type
- --wav
-
Produce a WAV file, or for more than 2 channels, a WAVEX file.
This is the default.
- --amb
-
Produce a WAVEX file with the Ambisonic GUID. Such files should
have the
.amb
filename extension.
- --caf
-
Produce a Core Audio file.
- --aiff
-
Produce an AIFF file.
- --flac
-
Produce a FLAC file.
Output sample format
- --16bit
-
Output sample format is signed 16-bit. This option also
enables the use of dithering, described below.
- --24bit
-
Output sample format is 24-bit. This is the default.
- --float
-
Output sample format is 32-bit floating point.
Dithering
- --rec
-
Add white dithering noise with a rectangular distribution. This
is the best option if the output data is going to processed again,
but in that case it would be advisable to use 24-bit or float.
- --tri
-
Add filtered noise with a triangular distribution. Compared to the
rectangular dither this reduces the noise density in the lower
frequency range.
- --lips
-
This uses the optimal error feedback filter described by
Stanley Lipschitz. This is recommended is the output is the
final distribution format, e.g. for a CD.
Timing
- --pad
-
Insert zero valued input samples at the start and end so that the output
includes the full symmetric filter response even for the first and last
samples.
EXIT STATUS
Zero in case there are no errors, non-zero otherwise.
AUTHOR
Fons Adriaensen (fons (at) linuxaudio.org)