User`s guide

Buffer
5-43
You can use the rebuffer_delay function with a frame size of 1 to precisely
compute the delay (in samples) for sample-based signals. For the above
example,
d = rebuffer_delay(1,3,1)
d =
4
This agrees with the four samples of delay (zeros) per channel shown in the
figure above.
Frame-Based Operation
In frame-based operation, the Buffer block redistributes the samples in the
input frame to an output frame with a new size and rate. A sequence of M
i
-by-N
matrix inputs is buffered into a sequence of M
o
-by-N frame-based matrix
outputs, where M
o
is the output frame size specified by the Output buffer size
parameter (i.e., the number of consecutive samples from the input frame to
buffer into the output frame). M
o
can be greater or less than the input frame
size, M
i
. Each of the N input channels is buffered independently.
The
Buffer overlap parameter, L, specifies the number of samples (rows) from
the current output to repeat in the next output, where L < M
o
. For 0 ≤ L < M
o
,
the number of new input samples the block acquires before propagating the
buffered data to the output is the difference between the
Output buffer size
and
Buffer overlap, M
o
-L.
The input frame period is M
i
∗T
si
, where T
si
is the sample period. The output
frame period is (M
o
-L)∗T
si
, which is equal to the sequence sample period when
the
Buffer overlap is M
o
-1. The output sample period is therefore related to
the input sample period by
Negative
Buffer overlap values are not permitted.
In the model below, the block buffers a two-channel frame-based input using a
Output buffer size of 3 and a Buffer overlap of 1.
T
so
M
o
L–()T
si
M
o
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