14-06-2012, 05:33 PM
Image Edge Detection Based on FPGA
Abstract
Field Programmable Gate Array (FPGA) is an
effective device to realize real-time parallel processing of vast
amounts of video data because of the fine-grain reconfigurable
structures.
INTRODUCTION
The edges of image are considered to be most important
image attributes that provide valuable information for human
image perception [1-3]. The edge detection is a terminology
in image processing, particularly in the areas of feature
extraction, to refer to algorithms which aim at identifying
points in a digital image at which the image brightness
changes sharply [4-6].
SOBEL EDGE DETECTION ENHANCEMENT
ALOGRITHM
In edge detection, the Sobel operator is used commonly.
The Sobel operator is a classic first order edge detection
operator, computing an approximation of the gradient of the
image intensity function. At each point in the image, the
result of the Sobel operator is the corresponding norm of this
gradient vector. The Sobel operator only considers the two
orientations which are 0°and 90°convolution kernels. The
operator uses the two kernels which are convolved with the
original image to calculate approximations of the gradient.
FPGA HARDWARE IMPLEMENTATION
This design uses 3×3 convolution kernels, processing
1024×1024×8 Gray Scale Image. The architecture is shown
in Fig.2.The system is divided into four modules: 3×3 pixel
generation module, Sobel enhancement operator module
edges control module and binary segmentation [10,11].
EXPERIMENTAL RESULTS
The design was implemented in the XILINX Spartan3
XC3S200 FPGA by ISE9.2. The device utilisation summary
is given in Table. I. Small resource is taken up, so there is
possibility of implementing some more parallel processes
with this architecture on the same FPGA.
CONCLUSION
The Sobel operator adding the orientation of the
convolution kernels can locate accurately the edge, thin the
boundary lines, and not be sensitive to noise. The FPGA
implementation of it meets the real-time requirements. This
architecture based on FPGA is much better than processing
images on software platform using high level programming
languages like C or C++ [13].
Abstract
Field Programmable Gate Array (FPGA) is an
effective device to realize real-time parallel processing of vast
amounts of video data because of the fine-grain reconfigurable
structures.
INTRODUCTION
The edges of image are considered to be most important
image attributes that provide valuable information for human
image perception [1-3]. The edge detection is a terminology
in image processing, particularly in the areas of feature
extraction, to refer to algorithms which aim at identifying
points in a digital image at which the image brightness
changes sharply [4-6].
SOBEL EDGE DETECTION ENHANCEMENT
ALOGRITHM
In edge detection, the Sobel operator is used commonly.
The Sobel operator is a classic first order edge detection
operator, computing an approximation of the gradient of the
image intensity function. At each point in the image, the
result of the Sobel operator is the corresponding norm of this
gradient vector. The Sobel operator only considers the two
orientations which are 0°and 90°convolution kernels. The
operator uses the two kernels which are convolved with the
original image to calculate approximations of the gradient.
FPGA HARDWARE IMPLEMENTATION
This design uses 3×3 convolution kernels, processing
1024×1024×8 Gray Scale Image. The architecture is shown
in Fig.2.The system is divided into four modules: 3×3 pixel
generation module, Sobel enhancement operator module
edges control module and binary segmentation [10,11].
EXPERIMENTAL RESULTS
The design was implemented in the XILINX Spartan3
XC3S200 FPGA by ISE9.2. The device utilisation summary
is given in Table. I. Small resource is taken up, so there is
possibility of implementing some more parallel processes
with this architecture on the same FPGA.
CONCLUSION
The Sobel operator adding the orientation of the
convolution kernels can locate accurately the edge, thin the
boundary lines, and not be sensitive to noise. The FPGA
implementation of it meets the real-time requirements. This
architecture based on FPGA is much better than processing
images on software platform using high level programming
languages like C or C++ [13].