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*Hello:*

I am new to coding in C6713 environment.  I am trying to implement
*LPC*analysis code (linear predictor).  To compute the coefficient set
alpha_k
for a set of time samples and reflection coefficients (k), I need to compute
auto correlation matrix.  The autocorrelation matrix computation involves
finding a Hermitian complex conjugate and a transpose operation.  I have
some questions:
   1. Do these functions to find *complex conjugate*, and *transpose* part
   of any library?  I tried checking the math library but was not able to find
   it.
   2. How do I get familiar with available functions quickly?  Is there a
   library for signal processing?  I saw a function that does the FFT.
   3. The math library has functions that generate sinusoidal values (cos.c,
   sin.c, cot.c etc).  But I am not able to access the actual functions that
   does that.  I am able to use it just by including the header in my source
   file.  Is there any way to look into the actual code and set break points
   and see what happens in memory?
   4. Do I need to do an audio analysis code for this (by setting analysis
   frame rate, hop size, windowing etc) (or) should I process block of samples
   by initializing an array and update it using a circular buffer?
   5. I assume that by using *View/Graph/time-Frequency* and *setting the
   start address* in the graph property dialog to the *address of the
   variable that holds the prediction coefficients*, I should be able to
   view the linear prediction analysis spectrum for predictor order P in
   frequency domain.  Am I right?
   6. What is the difference between a forward prediction and backward
   prediction and what link does it have to the *Levinson-Durbin
   (Autocorrelation based)* algorithm?  I do see that the difference
   equations are different but what difference can it make to the prediction?
    What are its advantages and disadvantages?
   7. I am using the *Rulph Chassaing book* and there seems to be 2 ways of
   doing this:
   - #define DSK6713_AIC23_INPUT_LINE 0x0011 (Input through line-in)
   and #define DSK6713_AIC23_INPUT_MIC 0x0015 and use the microphone input
   samples as input into the linear predictor
   - Other method is to define a sine table or use the sin.c function and
   create a data array and use it as an input to prove the performance of the
   linear predictor.  Am I right?

I would appreciate any reply regarding this.

Thanks.

Regards,
*Peter L*

*Text Reference*:  L.R. Rabiner, R.W. Schafer, Digital processing of speech
signals

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