function[sqnr,a_quan,code]=mula_pcm(a,n,mu)
%MULA_PCM MU-LAW PCM encoding of a sequence.
%[SQNR,A_QUAN,CODE]=MULA_PCM(A,N,MU)
%a=input sequence
%n=number of quantization levels(even)
%sqnr=output SQNR(in db)
%a_quan=quantized output before encoding.
%code=the encoded output.
[y,maximum]=mulaw(a,mu);%
[sqnr,y_q,code]=u_pcm(y,n);%
a_quan=invmulaw(y_q,mu);%
a_quan=maximum*a_quan;%
sqnr=20*log10(norm(a)/norm(a-a_quan));%