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In file ../include/sigpr/EST_filter.h:<TABLE BORDER=0><TR>
<TD VALIGN=TOP><H2>void <A HREF="#DOC.DOCU">FIR_double_filter</A></H2></TD><TD><H2>(<!1><A HREF="EST_Wave.html">EST_Wave</A> &in_sig,<BR> <!1><A HREF="EST_Wave.html">EST_Wave</A> &out_sig,<BR> const <!1><A HREF="EST_FVector.html">EST_FVector</A> &numerator)</H2></TD></TR></TABLE>
<BLOCKQUOTE>General purpose FIR double (zero-phase) filter.</BLOCKQUOTE>
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<H2>Documentation</H2>
<BLOCKQUOTE>General purpose FIR double (zero-phase) filter. This function
will double filter the waveform <TT>sig</TT> with a previously designed
filter, given as <TT>numerator</TT>. The filter coefficients can be
designed using one of the designed functions,
e.g. <!1><A HREF="design_FIR_filter.html">design_FIR_filter</A>. Double filtering is performed by
filtering the signal normally, resversing the waveform, filtering
again and reversing the waveform again. Normal filtering will impose a
lag on the signal depending on the order of the filter. By filtering
the signal forwards and backwards, the lags cancel each other out and
the output signal is in phase with the input signal.
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<DL><DT><DT><B>See Also:</B><DD><!1><A HREF="design_FIR_filter.html">design_FIR_filter</A>, <!1><A HREF="design_lowpass_FIR_filter.html">design_lowpass_FIR_filter</A>, <!1><A HREF="design_highpass_FIR_filter.html">design_highpass_FIR_filter</A>,
<BR><!1><A HREF="FIRfilter.html">FIRfilter</A>, <!1><A HREF="FIRlowpass_filter.html">FIRlowpass_filter</A>, <!1><A HREF="FIRhighpass_filter.html">FIRhighpass_filter</A> <BR><DD></DL><P><P><I><A HREF="index.html">Alphabetic index</A></I> <I><A HREF="HIER.html">HTML hierarchy of classes</A> or <A HREF="HIERjava.html">Java</A></I></P><HR>
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<P Align=left><I>This page is part of the
<A HREF="http://www.cstr.ed.ac.uk/projects/speech_tools.html">
Edinburgh Speech Tools Library</A> documentation
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Copyright <A HREF="http://www.ed.ac.uk"> University of Edinburgh</A> 1997
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Contact: <A HREF="mailto:speech_toolss@cstr.ed.ac.uk">
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