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.TH "DOWNSAMPLE" "" "July 2014" "" "Downsample Usage Information"
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.SH "NAME"
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.nf
downsample
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.fi
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.SH "SYNOPSIS"
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.nf
downsample <input\-rate> <downsamping\-ratio> [<gain>] <in\.raw >out\.txt
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.fi
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.SH "DESCRIPTION"
Extract the audio from the CD or tape at 44100Hz as a WAV or RAW audio file (i\.e\. 16\-bit stereo little\-endian data)\. You\'ll need a RAW (headerless) file to work on, but as a short\-cut you can treat a 16\-bit WAV file as a RAW file \-\- the worst that can happen is that the L+R channels get swapped and there is a bit of noise at the start of the recording\.
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.P
The point of downsampling is to reduce the amount of data that needs to be processed later, speeding up the process\. A sampling rate of 2004\.5Hz leaves everything up to ~700Hz intact\. If you are looking at higher carrier frequencies, you\'ll need to use a higher sampling rate when you downsample, and it will be a bit slower to run\.
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.SH "EXAMPLE"
Downsample this RAW file to 2004\.5Hz using \'downsample\':
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.IP "" 4
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.nf
downsample 44100 22 <in\.raw >out\.raw
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.fi
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.IP "" 0
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