DEVICES INCORPORATED
Video Imaging Products
2-1
LF2301
Image Resampling Sequencer
Image Resampling Sequencer
08/16/2000–LDS.2301-H
K
40 MHz Clock Rate
K
High-Speed Image Manipulation
K
Maximum Image Size: 4096 x 4096
Pixels
K
Supports Following Interpolation
Algorithms:
Nearest-Neighbor
Bilinear Interpolation
Cubic Convolution
K
Applications:
Video Special-Effects
Image Recognition
High-Speed Data Encoding/
Decoding
K
Replaces TRW/Raytheon/Fairchild
TMC2301
K
68-pin PLCC, J-Lead
FEATURES
DESCRIPTION
DEVICES INCORPORATED
LF2301 B
LOCK
D
IAGRAM
SOURCE
ADDRESS
GENERATOR
TARGET
ADDRESS
GENERATOR
INPUT IMAGE
BOUNDARY
COMPARATOR
ACC
WEN
LDR
B
3-0
P
11-0
INTER
INIT
NOOP
PARAMETER
STORAGE
CONTROL
INTEGER
FRACTION
CZERO
U
11-0
UWRI
X
11-0
CA
7-0
WALK COUNT
OETA
The
LF2301
is a self-sequencing
address generator designed to filter
a two-dimensional image or remap
and resample it from one set of
Cartesian coordinates (x,y) into a
new set (u,v).
The LF2301 can resample digitized
images or perform such manipula-
tions as rotation, panning, zooming,
and warping as well as compression
in real-time.
By using two LF2301s in a Image
Transformation System (ITS),
nearest-neighbor, bilinear interpola-
tion, and cubic convolution algo-
rithms, with kernel sizes up to 4 x 4
pixels, are all possible (see Figure 1).
This system can also implement
simple static filters with kernel sizes
up to 16 x 16 pixels.
DETAILS OF OPERATION
Most video applications use a pair
of LF2301s in tandem to construct
an ITS. One LF2301 is the row
coordinate generator (x to u) and the
other is the column generator (y to
v). External RAM is needed for
storage of the interpolation coeffi-
cient lookup table, as well as for
buffers of the source and destination
images. An external Multiplier-
Accumulator is required when
performing interpolation or imple-
menting static filters.
The ITS is capable of performing the
general second-order coordinate
transformation of the form:
x(u,v) = Au
2
+Bu+Cuv+Dv
2
+Ev+F
y(u,v) = Gu
2
+Hu+Kuv+Lv
2
+Mv+N
where parameters A through N of
the transform are user-defined.
The system steps sequentially
through each pixel in the “target”
image lying within a user-defined
rectangle. For each “target” pixel
at (u,v), the LF2301 points to a
corresponding “source” pixel at
(x,y).