<sect1 id='sigfilter-manual'>
	<title><command>sigfilter</command> <emphasis>Filter waveforms</emphasis></title>

    <toc depth='1'></toc>
    <para>
    </para>
    <sect2>
      <title>Synopsis</title>
      <para>
      </para>
        <!-- /amd/projects/festival/versions/v_mpiro/speech_tools_linux/bin/sigfilter -sgml_synopsis -->
        <para>
<cmdsynopsis><command>sigfilter</command>[input file0] -o [output file]<arg>-h </arg>
<arg>-itype <replaceable>string</replaceable></arg>
<arg>-n <replaceable>int</replaceable></arg>
<arg>-f <replaceable>int</replaceable></arg>
<arg>-ibo <replaceable>string</replaceable></arg>
<arg>-iswap </arg>
<arg>-istype <replaceable>string</replaceable></arg>
<arg>-c <replaceable>string</replaceable></arg>
<arg>-start <replaceable>float</replaceable></arg>
<arg>-end <replaceable>float</replaceable></arg>
<arg>-from <replaceable>int</replaceable></arg>
<arg>-to <replaceable>int</replaceable></arg>
<arg>-o <replaceable>ofile</replaceable></arg>
<arg>-otype <replaceable>string</replaceable></arg>
<arg>-F <replaceable>int</replaceable></arg>
<arg>-obo <replaceable>string</replaceable></arg>
<arg>-oswap </arg>
<arg>-ostype <replaceable>string</replaceable></arg>
<arg>-scale <replaceable>float</replaceable></arg>
<arg>-scaleN <replaceable>float</replaceable></arg>
<arg>-double </arg>
<arg>-lpfilter <replaceable>int</replaceable></arg>
<arg>-hpfilter <replaceable>int</replaceable></arg>
<arg>-forder <replaceable>int</replaceable></arg>
<arg>-lpcfilter <replaceable>ifile</replaceable></arg>
<arg>-firfilter <replaceable>ifile</replaceable></arg>
<arg>-inv_filter </arg>
</cmdsynopsis>
        </para>
        <!-- DONE /amd/projects/festival/versions/v_mpiro/speech_tools_linux/bin/sigfilter -sgml_synopsis -->
      <para>

<command>sigfilter</command> filters an input waveform and prduces a 
output waveform.
      </para>
    </sect2>
    <sect2>
      <title>Options</title>
      <para>
      </para>
        <!-- /amd/projects/festival/versions/v_mpiro/speech_tools_linux/bin/sigfilter -sgml_options -->
        <para>
<variablelist>
<varlistentry><term>-h</term>
<LISTITEM><PARA>

Options help 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-itype</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Input file type (optional). If set to raw, this 
indicates that the input file does not have a header. While 
this can be used to specify file types other than raw, this is 
rarely used for other purposes 
as the file type of all the existing supported 
types can be determined automatically from the 
file's header. If the input file is unheadered, 
files are assumed to be shorts (16bit). 
Supported types are 
nist, est, esps, snd, riff, aiff, audlab, raw, ascii 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-n</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Number of channels in an unheadered input file 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-f</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Sample rate in Hertz for an unheadered input file 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-ibo</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Input byte order in an unheadered input file: 
possibliities are: MSB , LSB, native or nonnative. 
Suns, HP, SGI Mips, M68000 are MSB (big endian) 
Intel, Alpha, DEC Mips, Vax are LSB (little 
endian) 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-iswap</term>
<LISTITEM><PARA>

Swap bytes. (For use on an unheadered input file) 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-istype</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Sample type in an unheadered input file: 
short, mulaw, byte, ascii 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-c</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Select a single channel (starts from 0). 
Waveforms can have multiple channels. This option 
extracts a single channel for progcessing and 
discards the rest. 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-start</term>
<LISTITEM><PARA>
<replaceable>float</replaceable>

Extract sub-wave starting at this time, specified in 
seconds 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-end</term>
<LISTITEM><PARA>
<replaceable>float</replaceable>

Extract sub-wave ending at this time, specified in 
seconds 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-from</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Extract sub-wave starting at this sample point 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-to</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Extract sub-wave ending at this sample point 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-o</term>
<LISTITEM><PARA>
<replaceable>ofile</replaceable>

Output filename. If not specified output is 
to stdout. 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-otype</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Output file type, (optional). If no type is 
Specified the type of the input file is assumed. 
Supported types are: 
nist, est, esps, snd, riff, aiff, audlab, raw, ascii 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-F</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Output sample rate in Hz. If this is different 
from the input sample rate, resampling will occur 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-obo</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Output byte order: MSB, LSB, native, or nonnative. 
Suns, HP, SGI Mips, M68000 are MSB (big endian) 
Intel, Alpha, DEC Mips, Vax are LSB 
(little endian) 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-oswap</term>
<LISTITEM><PARA>

Swap bytes when saving to output 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-ostype</term>
<LISTITEM><PARA>
<replaceable>string</replaceable>

Output sample type: short, mulaw, byte or ascii 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-scale</term>
<LISTITEM><PARA>
<replaceable>float</replaceable>

Scaling factor. Increase or descrease the amplitude 
of the whole waveform by the factor given 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-scaleN</term>
<LISTITEM><PARA>
<replaceable>float</replaceable>

Scaling factor with normalization. 
The waveform is scaled to its maximum level, after which 
it is scaled by the factor given 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-double</term>
<LISTITEM><PARA>

Perform double filtering by applying a forward filter, 
then a backward filter, leaving the filtered signla in phase 
with the original 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-lpfilter</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Low pass filter, with cutoff frequency in Hz 
Filtering is performed by a FIR filter which is built at run 
time. The order of the filter can be given by -forder. The 
default value is 199 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-hpfilter</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

High pass filter, with cutoff frequency in Hz 
Filtering is performed by a FIR filter which is 
built at run time. The order of the filter can 
be given by -forder. The default value is 199. 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-forder</term>
<LISTITEM><PARA>
<replaceable>int</replaceable>

Order of FIR filter used for lpfilter and 
hpfilter. This must be ODD. Sensible values range 
from 19 (quick but with a shallow rolloff) to 199 
(slow but with a steep rolloff). The default is 199. 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-lpcfilter</term>
<LISTITEM><PARA>
<replaceable>ifile</replaceable>

Track file containing lpc filter coefficients 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-firfilter</term>
<LISTITEM><PARA>
<replaceable>ifile</replaceable>

File containing a single set of FIR filter 
coefficients 
</PARA></LISTITEM>
</varlistentry>

<varlistentry><term>-inv_filter</term>
<LISTITEM><PARA>

use filter coefficients for inverse filtering </PARA></LISTITEM>
</varlistentry>
</variablelist>
        </para>
        <!-- DONE /amd/projects/festival/versions/v_mpiro/speech_tools_linux/bin/sigfilter -sgml_options -->
    </sect2>
  </sect1>