Reference no: EM13871586

1. Write a speech encoder using the LPC algorithm. You must implement your own LPCcode. You must not use any MATLAB toolboxes { use the 'which' command in MATLABto check if a function is built-in or contained in a toolbox. Use the following parameters:

1. A frame size of 200 samples;2. 10th order prediction;3. Single-pulse excitation at the start of the frame;4. RMS energy normalization. Include a listing of the code and an explanation (in your own words) of each stage of theencoding. Comment on the audio quality of the reconstructed speech in terms of intelligibility and naturalness using a male speaker and a female speaker. Then encode the musicdata using the coder and comment on the result.

2. Vary the frame size over what you consider to be a \reasonable" range and comment on theaudio quality of the reconstructed speech using male and female speakers.For each frame size and speaker, tabulate the bit rate in bits per second (bps) requiredusing 8-bit scalar quantization for the RMS energy parameter and each of the ten LPCcoefficients.

3. For the optimal frame size found above, vary the number of LPC parameters. Is 10 areasonable choice?

4. Enhance the coder using pitch information, as follows. For each frame, calculate the pitchusing autocorrelation. Then generate the excitation using impulses spaced at the pitch interval. Test using male and female speakers, and comment on any improvements younotice over single-pulse excitation. Note that you may need to buer one or more previousframes in order to calculate the correlation, and that the placement of the pitch impulsesin the current frame depends on the location of the last pitch pulse in the previous frame.Include a listing of the code and an explanation (in your own words) of each stage of theencoding.Comment on the perceived quality of the LPC coder with pitch excitation as compared tosingle-pulse excitation.