ref: c97d3bb141f953c4aa07a4462fe2495a53b0e1c9
parent: 3517e47f2ea95aeca12585e94a7d02955b8ed738
author: Ulrich Klauer <ulrich@chirlu.de>
date: Mon Oct 15 23:08:01 EDT 2012
Clarify speed effect documentation Make it clearer in the man page that the speed effect actually only changes the sample rate field in the signal information. It should be less surprising then to libSoX users that they have to add the rate effect, too.
--- a/sox.1
+++ b/sox.1
@@ -3306,8 +3306,10 @@
which the pitch (and tempo) should be adjusted: greater than 0
increases, less than 0 decreases.
.SP
-By default, the speed change is performed by resampling with the \fBrate\fR
-effect using its default quality/speed. For higher quality or higher speed
+Technically, the speed effect only changes the sample rate information,
+leaving the samples themselves untouched. The \fBrate\fR effect is invoked
+automatically to resample to the output sample rate, using its default
+quality/speed. For higher quality or higher speed
resampling, in addition to the \fBspeed\fR effect, specify
the \fBrate\fR effect with the desired quality option.
.SP