voicebox speech processing toolbox for matlab.htm

MATLAB工具箱 内容挺丰富

<HR>

<H2><A name=fourier>Fourier, DCT and Hartley Transforms</A></H2>
<UL>
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/rfft.txt">rfft</A>, and 
  <A href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/irfft.txt">irfft</A> 
  perform forward and inverse fourier transforms on real data. Only half of the 
  conjugate symmetric transform is generated by the forward routine RFFT. For 
  even length data, the inverse routine, IRFFT, is asymptotically twice as fast 
  as the built-in fft routine IFFT. The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/rsfft.txt">rsfft 
  </A>performs the forward transform on real symmetric data. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/rdct.txt">rdct</A>, and 
  <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/irdct.txt">irdcft</A> 
  perform forward and inverse discrete cosine transforms on real data. The 
  routines are asymptotically twice as fast as the complex-data routines in the 
  image-processing and signal-processing toolboxes. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/rhartley.txt">rhartley 
  </A>performs a forward or inverse Hartley transform. </LI></UL>
<HR>

<H2><A name=random>Random Number Generation</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/randvec.txt">randvec 
  </A>generates random vectors with a given mean and covariance. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/usasi.txt">usasi 
  </A>generates noise with a USASI spectrum. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/randfilt.txt">randfilt</A> 
  generates filtered gaussian noise without any startup transients. </LI></UL>
<HR>

<H2><A name=distance>Vector Distance</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/disteusq.txt">disteusq 
  </A>calculates the squared euclidean distance between all pairs of rows of two 
  matrices. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distitar.txt">distitar</A>, 
  <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distisar.txt">distisar</A> 
  and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distchar.txt">distchar</A> 
  calculate the Itakura, Itakura-Saito and COSH spectral distances between sets 
  of AR coefficients. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distitpf.txt">distitpf</A>, 
  <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distispf.txt">distispf</A> 
  and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/distchpf.txt">distchpf</A> 
  calculate the Itakura, Itakura-Saito and COSH spectral distances between power 
  spectra. </LI></UL>
<HR>

<H2><A name=analysis>Speech Analysis</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/enframe.txt">enframe</A> 
  can be used to split a signal up into frames. It can optionally apply a window 
  to each frame. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/activlev.txt">activlev 
  </A>calculates the active level of a speech segment according to ITU-T 
  recommendation P.56. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/spgrambw.txt">spgrambw 
  </A>draws a monochrome spectrogram with a dB scale. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/schmitt.txt">schmitt 
  </A>passes a signal through a schmitt trigger. </LI></UL>
<HR>

<H2><A name=enhance>Speech Enhancement</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/specsubm.txt">specsubm</A> 
  implements spectral subtraction using an algorithm of Martin. </LI></UL>
<HR>

<H2><A name=lpc>LPC Analysis of Speech</A></H2>
<UL>
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpcauto.txt">lpcauto</A> 
  and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpccovar.txt">lpccovar</A> 
  perform linear predictive coding (LPC) analysis. The routines relating to LPC 
  are described in more detail on <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/lpc.html">another page</A>. 
  A large number of <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/lpc.html">conversion 
  routines</A> are included for changing the form of the LPC coefficients (e.g. 
  AR coefficients, reflection coefficients etc.): these are of the form lpcxx2yy 
  where xx and yy denote the coefficient sets. The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpcrr2am.txt">lpcrr2am 
  </A>calculates LPC filters for all orders up to a given maximum. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpcbwexp.txt">lpcbwexp 
  </A>performs bandwidth expansion on an LPC filter. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/ccwarpf.txt">ccwarpf 
  </A>performs frequency warping in the complex cepstrum domain. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpcifilt.txt">lpcifilt 
  </A>performs inverse filtering to estimate the glottal waveform from the 
  speech signal and the lpc coefficients. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lpcrand.txt">lpcrand</A> 
  can be used to generate random, stable filters for testing purposes. </LI></UL>
<HR>

<H2><A name=synthesis>Speech Synthesis</A></H2>
<UL>
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/glotros.txt">glotros</A> 
  and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/glotlf.txt">glotlf</A> 
  implement two common models for the waveform of airflow through the vocal 
  folds. </LI></UL>
<HR>

<H2><A name=coding>Speech Coding</A></H2>
<UL>
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lin2pcma.txt">lin2pcma</A>, 
  <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/lin2pcmu.txt">lin2pcmu</A>, 
  <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/pcma2lin.txt">pcma2lin</A>, 
  and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/pcmu2lin.txt">pcmu2lin</A> 
  convert audio waveforms to and from the 8-bit A-law and Mu-law PCM formats 
  that are used in telecommunications: Mu-law is used in the USA and Japan while 
  A-law is used in the rest of the world. The two formats are very similar and, 
  for speech waveforms, give about the same perceived quality as 12-bit linear 
  encoding. Alternate bits in the A-law format are usually inverted before 
  transmission: the conversion routines can optionally include this. The 
  conversions are defined by ITU standard G.711. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/kmeans.txt">kmeans 
  </A>and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/kmeanlbg.txt">kmeanlbg 
  </A>perform vector quantisation using the kmeans algorithm. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/potsband.txt">potsband 
  </A>calculates a bandpass filter corresponding to the standard telephone 
  passband. </LI></UL>
<HR>

<H2><A name=recog>Speech Recognition</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/melcepst.txt">melcepst 
  </A>implements a mel-cepstrum front end for a recogniser. The associated 
  bandpass filter matrix is generated by <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/melbankm.txt">melbankm 
  </A>. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/cep2pow.txt">cep2pow 
  </A>and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/pow2cep.txt">pow2cep 
  </A>convert state means and variances between the mel-cepstrum and power 
  domains. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/gaussmix.txt">gaussmix</A> 
  fits a gaussian mixture distribution to a collection of observation vectors. 
  </LI></UL>
<HR>

<H2><A name=utility>Utility Functions</A></H2>
<UL>
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/zerotrim.txt">zerotrim 
  </A>removes from a matrix any trailing rows and columns that are all zero. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/logsum.txt">logsum</A> 
  calculates log(sum(exp(x))) without overflow problems. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/dualdiag.txt">dualdiag</A> 
  simultaneously diagonalises two matrices: this is useful in computing LDA or 
  IMELDA transforms. 
  <LI>The routines <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/permutes.txt">permutes 
  </A>and <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/choosenk.txt">choosenk 
  </A>generate respectively all possible permutations of the numbers 1:n and all 
  possible ways of choosing k elements out of the numbers 1:n without 
  duplications. They are equivalent to the standard <B 
  style="BACKGROUND-COLOR: #ffff66; COLOR: black">MATLAB</B> routines PERMS and 
  NCHOOSEK but much faster. 
  <LI>The routine <A 
  href="http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/txt/zerotrim.txt">sprintsi 
  </A>prints a value with the correct standard SI multiplier (e.g. 2100 prints 
  as 2.1 k). </LI></UL></BODY></HTML>