[prev in list] [next in list] [prev in thread] [next in thread] 

List:       sox-devel
Subject:    [SoX-devel] [ sox-Bugs-3578875 ] sox-win downsampling not working
From:       SourceForge.net <noreply () sourceforge ! net>
Date:       2012-10-21 15:54:32
Message-ID: E1TPxrG-0006x3-2i () sfs-ml-2 ! v29 ! ch3 ! sourceforge ! com
[Download RAW message or body]

Bugs item #3578875, was opened at 2012-10-21 03:07
Message generated for change (Comment added) made by robs
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=110706&aid=3578875&group_id=10706

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: None
Group: None
Status: Closed
Resolution: Invalid
Priority: 5
Private: No
Submitted By: Dan (djmaguire)
Assigned to: Nobody/Anonymous (nobody)
Summary: sox-win downsampling not working

Initial Comment:
The downsample effect produces an output file equal in size to the input file (i.e., \
not decimated).  The rate effect does work properly (with an undesirable \
anti-aliasing filter, of course).  I am using it to process wav files.  I tried with \
three different wav files of varying size and produced from different sources.

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

> Comment By: robs (robs)
Date: 2012-10-21 08:54

Message:
> robs: This is about "downsample", not "rate". :-)
I managed to read "The rate effect does work properly" as "The rate effect
doesn't work properly"  Doh!

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

Comment By: Ulrich Klauer (uklauer)
Date: 2012-10-21 07:47

Message:
robs: This is about "downsample", not "rate". :-)

I think I know what is happening. You tried something like "sox
input-48000.wav output.wav downsample 4", right? The downsample effect
*does* work here, but SoX defaults to using the input file parameters for
the output file. So, as the input file had a sample rate of 48 kHz, the
output file gets 48 kHz, too. To achieve this, SoX automatically inserts
the rate effect, which resamples the downsampled version up again. So, to
make this work as expected, write "sox input-48000.wav -r 12000 output.wav
downsample 4".

Calling SoX with the -V option (note: capital V) will show you the actual
effects chain being used. For the first call, the output is:
sox INFO sox: effects chain: input        48000Hz  1 channels
sox INFO sox: effects chain: synth        48000Hz  1 channels
sox INFO sox: effects chain: gain         48000Hz  1 channels
sox INFO sox: effects chain: downsample   12000Hz  1 channels
sox INFO sox: effects chain: rate         48000Hz  1 channels
sox INFO sox: effects chain: output       48000Hz  1 channels

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

Comment By: robs (robs)
Date: 2012-10-21 06:56

Message:
I've just downloaded the latest version and tried it:

B:\Downloads\sox-14.4.0-win32>sox -n 48.wav synth 10 sin 0:24k gain -1

B:\Downloads\sox-14.4.0-win32>sox 48.wav 44.wav rate 44100

B:\Downloads\sox-14.4.0-win32>sox --i *.wav

Input File     : '44.wav'
Channels       : 1
Sample Rate    : 44100
Precision      : 32-bit
Duration       : 00:00:10.00 = 441000 samples = 750 CDDA sectors
File Size      : 1.76M
Bit Rate       : 1.41M
Sample Encoding: 32-bit Signed Integer PCM


Input File     : '48.wav'
Channels       : 1
Sample Rate    : 48000
Precision      : 32-bit
Duration       : 00:00:10.00 = 480000 samples ~ 750 CDDA sectors
File Size      : 1.92M
Bit Rate       : 1.54M
Sample Encoding: 32-bit Signed Integer PCM

Total Duration of 2 files: 00:00:20.00

The decimated file is smaller, as expected.

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

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=110706&aid=3578875&group_id=10706

------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_sfd2d_oct
_______________________________________________
SoX-devel mailing list
SoX-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sox-devel


[prev in list] [next in list] [prev in thread] [next in thread]