How to change the frequency of a wav file using PIC ?

[piskot]

hi everyone

my teacher wants me to change the frequency of an audio file(in .wav) using microcontroller. is it possible?
the wav file will be read from matlab using wavread. the data from matlab , consist of the wave vector, and sampling freq will be used.
if it is possible how can i do it. can anyone give me a clue?

thank you

Added after 55 minutes:

its like an audio frequency changer but only short audio file. say a recorded "hello" voice.

 

[zristic]

Re: wav file to pic

It is very simple, make a PWM output, with the frequency of, let's say, 8KHz (depending on the max frequency in wav file- make PWM frequency double), then change the duty cycle proportionaly to amplitude of the sample. Finally, take the generated PWM signal to RC filter and there you have it.

I tried it with 18F8722 + CF card + mikroPascal and it works great.


EDIT:
Changing the frequency of PWM will make the voice faster or slower...