Bugs item #3578875, was opened at 2012-10-21 03:07 Message generated for change (Comment added) made by uklauer 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: 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 [email protected] https://lists.sourceforge.net/lists/listinfo/sox-devel
