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convolverPipe nPartitions nTuningRigour fAttenuationDB nFilterLengths MajorFormatIn MinorFormatIn MajorFormatOut MinorFormatOut config.txt|IR.wav

convolverPipe convolves the standard input stdin to the standard output stdout using the specified impulse response (IR) filter.

It uses the following parameters

0 for overlap-save, or the number of partitions to be used
Tuning rigour: 0-4 (Estimate, Measure, Patient, Exhaustive, or Take 1 minute)
The attenuation to be applied, in dB. Use the estimated, or the (ultra conservative) peak value
The number of filter lengths to be processed at a time

One of the following. The specified value will be over-ridden by the actual for input file format, unless RAW is selected.

WAV Microsoft WAV format (little endian).
AIFF Apple/SGI AIFF format (big endian).
AU Sun/NeXT AU format (big endian).
PAF Ensoniq PARIS file format.
SVX Amiga IFF / SVX8 / SV16 format.
NIST Sphere NIST format.
VOC VOC files.
W64 Sonic Foundry's 64 bit RIFF/WAV
MAT4 Matlab (tm) V4.2 / GNU Octave 2.0
MAT5 Matlab (tm) V5.0 / GNU Octave 2.1
PVF Portable Voice Format
XI Fasttracker 2 Extended Instrument
HTK HMM Tool Kit format
SDS Midi Sample Dump Standard
AVR Audio Visual Research
SD2 Sound Designer 2
FLAC FLAC lossless file format
CAF Core Audio File format
PCM_S8 Signed 8 bit data
PCM_16 Signed 16 bit data
PCM_24 Signed 24 bit data
PCM_32 Signed 32 bit data
PCM_U8 Unsigned 8 bit data (WAV and RAW only)
FLOAT 32 bit float data
DOUBLE 64 bit float data
ULAW U-Law encoded.
ALAW A-Law encoded.
GSM610 GSM 6.10 encoding.
VOX_ADPCM Oki Dialogic ADPCM encoding.
G721_32 32kbs G721 ADPCM encoding.
G723_24 24kbs G723 ADPCM encoding.
G723_40 40kbs G723 ADPCM encoding.
DWVW_12 12 bit Delta Width Variable Word encoding
DWVW_16 16 bit Delta Width Variable Word encoding
DWVW_24 24 bit Delta Width Variable Word encoding
DWVW_N N bit Delta Width Variable Word encoding
DPCM_8 8 bit differential PCM (XI only)
DPCM_16 16 bit differential PCM (XI only)
config.txt or IR.wav:
a config text file specifying a single filter path or a sound file to be used as a filter

These parameters are described more fully on the usage page.

Example usage: setting convolverPipe for use with SlimServer/SqueezeCenter

These instructions assume that you have Slimserver 6.x or 7.x installed and that you will be using it to playback Flac, APE or MP3 files .

I am grateful to Dino Nuhagic for providing them.

Step 1

  • Copy custom-convert.conf to C:\Program Files\SlimServer\server (for Slimserver 6.x) or C:\Program Files\SqueezeCenter\server (for SqueezeCenter 7.x). The file contains:
flc flc * *
  [flac] -dcs --skip=$START$ --until=$END$ -- $FILE$ | "C:\Program Files\Convolver\Convolver\convolverpipe.exe" 2 1 -6 1 WAV PCM_16 RAW PCM_24 "C:\Impulses\yourfilter.wav" | [flac] -cs --totally-silent --compression-level-0 --endian little --sign signed --channels 2 --bps 24 --sample-rate 44100 -

mp3 flc * *
	[lame] --mp3input --decode -t --silent $FILE$ - | "C:\Program Files\Convolver\Convolver\convolverpipe.exe" 2 1 -6 1 RAW PCM_16 RAW PCM_24 "C:\Impulses\yourfilter.wav" | [flac] -cs --totally-silent --compression-level-0 --endian little --sign signed --channels 2 --bps 24 --sample-rate 44100 -

ape flc * *
	[mac] $FILE$ - -d | "C:\Program Files\Convolver\Convolver\convolverpipe.exe" 2 1 -6 1 WAV PCM_16 RAW PCM_24 "C:\Impulses\yourfilter.wav" | [flac] -cs --totally-silent --compression-level-0 --endian little --sign signed --channels 2 --bps 24 --sample-rate 44100 -

Edit custom-convert.conf to reflect your own environment.  In particular,

  • C:\Impulses\yourfilter.wav should be the path to the stereo filter that you wish to use.  Alternatively you could use a config.txt file to specify your stereo filter(s).

  • C:\Program Files\Convolver\Convolver\convolverPipe.exe is the path to your convolverPipe.exe.  For example on 64bit OS it would be C:\Program Files (x86)\Convolver\Convolver\convolverPipe.exe

  • Do not change the [flac], it is an internal variable.

  • If your output device does not support 24-bit samples and you want to use 16-bit samples instead, change the RAW PCM_24 and --bps 24 parameters in the specification:

flc flc * *
    [flac] -dcs --skip=$START$ --until=$END$ -- $FILE$ | "C:\Program Files\Convolver\Convolver\convolverpipe.exe" 2 1 -6 1 WAV PCM_16 RAW PCM_16 "C:\Impulses\yourfilter.wav" | [flac] -cs --totally-silent --compression-level-0 --endian little --sign signed --channels 2 --bps 16 --sample-rate 44100 -

Step 2

  • Turn off SlimServer/SqueezeCenter by using the taskbar icon or (more brutally) end task in the Task Manager.
  • Then restart it after it has completely shut down.
  • Open Slimserver and navigate to Server Settings | File Types. (The location of these settings is in Settings | Advanced | File Types).  Depending what you want to convolve untick all the file format settings next to the Flac, MP3 or APE rows.   Then set them to these accordingly:
    •  Flac - (flac/flac)
    •  MP3 - (lame/flac)
    •  APE - (mac/flac)
  • That's it.
  • If you do not see the ConvolverPipe running in the Task Manager while playing back your music, or there is no sound, then check your File Type settings and the parameters in custom-convert.conf.
  • Make sure you restart the Server every time you change the custom-convert.conf file.


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Last modified: 16-Jan-2008 20:24 -0000 Logo