# v_lin2pcmu

## PURPOSE

V_LIN2PCMU Convert linear to Mu-law PCM P=(X,S)

## SYNOPSIS

function p=v_lin2pcmu(x,s)

## DESCRIPTION

    V_LIN2PCMU Convert linear to Mu-law PCM P=(X,S)
        pcmu = v_lin2pcmu(lin) where lin contains a vector
        or matrix of signal values within a range determined by
        the scale factor s (see table below).
        Values outside this range will be clipped.
        The input values will be converted to integer
        Mu-law pcm vlues in the range 0 to 255.

        Input values are multiplied by the scale factor s:

               s        Input Range

               1        +-8159
            4004.189931    +-2.03761563 (default)
            8159        +-1

        The default input scaling factor 4004.189931 is equal to
        sqrt((2207^2 + 5215^2)/2) and follows ITU standard G.711.
        The sine wave with PCM-Mu values [158 139 139 158 30 11 11 30]
        has a mean square value of unity corresponding to 0 dBm0.

## CROSS-REFERENCE INFORMATION

This function calls:

This function is called by:

- v_writewav V_WRITEWAV Creates .WAV format sound files FIDX=(D,FS,FILENAME,MODE,NSKIP,MASK,MAD)

## SOURCE CODE

    0001 function p=v_lin2pcmu(x,s)
    0002 %V_LIN2PCMU Convert linear to Mu-law PCM P=(X,S)
    0003 %    pcmu = v_lin2pcmu(lin) where lin contains a vector
    0004 %    or matrix of signal values within a range determined by
    0005 %    the scale factor s (see table below).
    0006 %    Values outside this range will be clipped.
    0007 %    The input values will be converted to integer
    0008 %    Mu-law pcm vlues in the range 0 to 255.
    0009 %
    0010 %    Input values are multiplied by the scale factor s:
    0011 %
    0012 %           s        Input Range
    0013 %
    0014 %           1        +-8159
    0015 %        4004.189931    +-2.03761563 (default)
    0016 %        8159        +-1
    0017 %
    0018 %    The default input scaling factor 4004.189931 is equal to
    0019 %    sqrt((2207^2 + 5215^2)/2) and follows ITU standard G.711.
    0020 %    The sine wave with PCM-Mu values [158 139 139 158 30 11 11 30]
    0021 %    has a mean square value of unity corresponding to 0 dBm0.
    0022
    0023
    0024
    0025 %      Copyright (C) Mike Brookes 1998
    0026 %      Version: $Id: v_lin2pcmu.m 10865 2018-09-21 17:22:45Z dmb $
    0027 %
    0028 %   VOICEBOX is a MATLAB toolbox for speech processing.
    0029 %   Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
    0030 %
    0031 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0032 %   This program is free software; you can redistribute it and/or modify
    0033 %   it under the terms of the GNU Lesser General Public License as published by
    0034 %   the Free Software Foundation; either version 3 of the License, or
    0035 %   (at your option) any later version.
    0036 %
    0037 %   This program is distributed in the hope that it will be useful,
    0038 %   but WITHOUT ANY WARRANTY; without even the implied warranty of
    0039 %   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    0040 %   GNU Lesser General Public License for more details.
    0041 %
    0042 %   You can obtain a copy of the GNU Lesser General Public License from
    0043 %   https://www.gnu.org/licenses/ .
    0044 %
    0045 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    0046
    0047 if nargin < 2 s=4004.189931; end
    0048 y=x*s;
    0049 y=(abs(y+8031)-abs(y-8031))/2;
    0050 q=floor((y+8032)/8032);
    0051 [m,e]=log2(abs(y)+33);
    0052 p=175+128*q-8*(e+abs(e-6))-floor(32*m-16);