Quantize and encode floating-point inputs to integer outputs
y = uencode(u,n)
y = uencode(u,n,v)
y = uencode(u,n,v,'SignFlag'
)
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,
maps
entries in a multidimensional array of floating-point numbers 'SignFlag'
)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 number of
quantization levels 2n and
the value of 'SignFlag'
, which 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.
uencode
maps the floating-point input value
to an integer value determined by the requirement for 2n levels
of quantization. This encoding adheres to the definition for uniform
encoding specified in ITU-T Recommendation G.701. The input range [-v,v]
is
divided into 2n evenly spaced intervals.
Input entries in the range [-v,v]
are first quantized
according to this subdivision of the input range, and then mapped
to one of 2n integers. The range of the
output depends on whether or not you specify that you want signed
integers.
[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.