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function y=uencode(u,n,v,signflag)
//Performs uniform quantization of the input into 2^n levels
//Calling Sequence
//y=uencode(u,n,v,'signflag')
//Parameters
//u
//A vector, matrix or n-dimensional array
//n
//An integer between 2 and 32
//v
//A positive real scalar
//'signflag'
//A string which can take only 2 values 'signed' or 'unsigned'
//Description
//Uniformly quantizes the input vector or n-dimensional array u into 2^n levels in the interval [-v,v]
//If v is not specified, its default value is 1
//'signflag' is a string that determines the nature of the quantization
//If signflag='unsigned' then y contains unsigned integers in the range [0,2^n-1] corresponding to the 2^n levels
//If signflag='unsigned' then y contains signed integers in the range [-2^(n-1),2^(n-1)-1] corresponding to the 2^n levels
//The size of the integers in y in bits(8,16, or 32) depends on the value of n
//If the input lies beyond +/- v it is saturated
//Example
//y=uencode(-1:0.5:1,3)
// y =
//
// 0 2 4 6 7
//Author
//Ankur Mallick
//References
//[1] International Telecommunication Union. General Aspects of Digital Transmission Systems: Vocabulary of Digital Transmission and Multiplexing, and Pulse Code Modulation (PCM) Terms. ITU-T Recommendation G.701. March, 1993.
//See also
//udecode
//floor
funcprot(0);
if(argn(2)<4)
signflag='unsigned';
if(argn(2)<3)
v=1;
end
end
if(argn(2)>4|argn(2)<2)
error('Incorrect number of input arguments.');
elseif(signflag~='signed'&signflag~='unsigned')
error('Sign flag must be signed or unsigned');
elseif(~isscalar(v)|abs(v)~=v)
error('Peak value must be a positive real scalar');
elseif(~isscalar(n)|round(n)~=n|n<2|n>32)
error('n must be an integer between 2 and 32')
else
if(or(imag(u(:))~=0))
//Complex Number
u_real=real(u);
y_real=uencode(u_real,n,v,signflag);
disp(type(y_real));
u_imag=imag(u);
y_imag=uencode(u_imag,n,v,signflag);
y=double(y_real)+%i*double(y_imag);
else
//Real Numbers
y=zeros(u);
L=2*v/(2^n);
y=floor((u+v)/L);
y(y<0)=0;
y(y>(2^n-1))=2^n-1;
if(signflag=='signed')
y=y-2^(n-1);
if(n>=2&n<=8)
y=int8(y);
elseif(n>=9&n<=16)
y=int16(y);
else
y=int32(y);
end
else
if(n>=2&n<=8)
y=uint8(y);
elseif(n>=9&n<=16)
y=uint16(y);
else
y=uint32(y);
end
end
end
end
endfunction
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