uencode() - Signal Processing

y = uencode(u,n) quantizes the entries in
a multidimensional array of floating-point numbers u and
encodes them as integers using 2n-level
quantization. n must
be an integer between 2 and 32 (inclusive). Inputs can be real or
complex, double- or single-precision. The output y and the input u are
arrays of the same size. The elements of the output y are unsigned
integers with magnitudes in the range [0, 2n-1].
Elements of the input u outside of the range [-1,1] are
treated as overflows and are saturated. For entries in the input u that
are less than -1, the value of the output of uencode is
0. For entries in the input u that
are greater than 1, the value of the output of uencode is
2n-1. y = uencode(u,n,v) allows
the input u to have entries with floating-point
values in the range [-v,v] before saturating them
(the default value for v is 1).
Elements of the input u outside of the range [-v,v] are
treated as overflows and are saturated:For input entries less than -v,
the value of the output of uencode is 0. For input entries greater than v,
the value of the output of uencode is 2n-1. y = uencode(u,n,v,'SignFlag') maps
entries in a multidimensional array of floating-point numbers u whose
entries have values in the range [-v,v] to an integer
output y. Input entries outside this range are
saturated. The integer type of the output depends on the string 'SignFlag' and
the number of quantization levels 2n. The
string 'SignFlag' can be one of the following:'signed': Outputs are signed integers
with magnitudes in the range [-2n/2, (2n/2) - 1].'unsigned' (default): Outputs are
unsigned integers with magnitudes in the range [0, 2n-1].The output data types are optimized for the number of bits as
shown in the table below.   nUnsigned IntegerSigned Integer
2 to 8uint8int8
9 to 16uint16int16
17 to 32uint32int32

Syntax

y = uencode(u,n)y = uencode(u,n,v)y = uencode(u,n,v,'SignFlag')

Example

Map Floating-Point Scalars to IntegersOpen This Example
Map floating-point scalars in [-1, 1] to uint8 (unsigned) integers. Produce a staircase plot. The horizontal axis ranges from -1 to 1 and the vertical axis from 0 to 7 (i.e., 
).
u = -1:0.01:1;
y = uencode(u,3);
plot(u,y,'.')

Look at saturation effects when you underspecify the peak value for the input.u = -2:0.5:2;
y = uencode(u,5,1)

y =

    0    0    0    8   16   24   31   31   31

Specify you want signed output.u = -2:0.5:2;
y = uencode(u,5,2,'signed')

y =

  -16  -12   -8   -4    0    4    8   12   15

Output / Return Value

Limitations

Alternatives / See Also

Reference