Bugs item #3590093, was opened at 2012-11-26 07:02 Message generated for change (Comment added) made by tartina You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=110706&aid=3590093&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: Open Resolution: None Priority: 5 Private: No Submitted By: Guido Aulisi (tartina) Assigned to: Nobody/Anonymous (nobody) Summary: Bad clipping using mcompand Initial Comment: When summing bands in mcompand I got some bad unnoticed clipping, and the samples wrapped from positive to negative and viceversa. With many bands sox_sample_t intergers get wrapped before being cast to double. I have a patch for this, I'll attach it. ---------------------------------------------------------------------- Comment By: Guido Aulisi (tartina) Date: 2012-12-10 02:56 Message: I created a test file for this bug (sox-test.flac). If sox is unpatched I get a bad clipping at sample 36298 (circa 0.823s) of the right channel using mcompand; the sample is wrapped from negative to positive and sox doesn't report the clipping. With the patch the sample remains at its most negative number and sox reports the clipping. These are the 2 commands: $ sox -V sox-test.flac out.wav mcompand ".08,.2 6:-90,-90,-20,-20,0,-10 4 -90" 200 ".04,.1 6:-90,-90,-20,-20,0,-10 4 -90" sox: SoX v14.4.0 sox INFO formats: detected file format type `flac' Input File : 'sox-test.flac' Channels : 2 Sample Rate : 44100 Precision : 16-bit Duration : 00:00:01.73 = 76149 samples = 129.505 CDDA sectors File Size : 194k Bit Rate : 899k Sample Encoding: 16-bit FLAC Endian Type : little Reverse Nibbles: no Reverse Bits : no sox INFO sox: Overwriting `out.wav' Output File : 'out.wav' Channels : 2 Sample Rate : 44100 Precision : 16-bit Duration : 00:00:01.73 = 76149 samples = 129.505 CDDA sectors Sample Encoding: 16-bit Signed Integer PCM Endian Type : little Reverse Nibbles: no Reverse Bits : no Comment : 'Processed by SoX' sox INFO sox: effects chain: input 44100Hz 2 channels sox INFO sox: effects chain: mcompand 44100Hz 2 channels sox INFO sox: effects chain: dither 44100Hz 2 channels sox INFO sox: effects chain: output 44100Hz 2 channels -------------------------------------------------------------------------------- $ patched_sox -V sox-test.flac out_patched.wav mcompand ".08,.2 6:-90,-90,-20,-20,0,-10 4 -90" 200 ".04,.1 6:-90,-90,-20,-20,0,-10 4 -90" sox: SoX v14.4.0 sox INFO formats: detected file format type `flac' Input File : 'sox-test.flac' Channels : 2 Sample Rate : 44100 Precision : 16-bit Duration : 00:00:01.73 = 76149 samples = 129.505 CDDA sectors File Size : 194k Bit Rate : 899k Sample Encoding: 16-bit FLAC Endian Type : little Reverse Nibbles: no Reverse Bits : no Output File : 'out_patched.wav' Channels : 2 Sample Rate : 44100 Precision : 16-bit Duration : 00:00:01.73 = 76149 samples = 129.505 CDDA sectors Sample Encoding: 16-bit Signed Integer PCM Endian Type : little Reverse Nibbles: no Reverse Bits : no Comment : 'Processed by SoX' sox INFO sox: effects chain: input 44100Hz 2 channels sox INFO sox: effects chain: mcompand 44100Hz 2 channels sox INFO sox: effects chain: dither 44100Hz 2 channels sox INFO sox: effects chain: output 44100Hz 2 channels sox WARN mcompand: mcompand clipped 1 samples; decrease volume? sox WARN dither: dither clipped 1 samples; decrease volume? ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=110706&aid=3590093&group_id=10706 ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ SoX-devel mailing list SoX-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sox-devel
