gusucode.com > vision工具箱matlab源码程序 > vision/+vision/en/EdgeDetector.m
classdef EdgeDetector< matlab.system.SFunSystem
%EdgeDetector Find edges of objects in images
% -----------------------------------------------------------------------
% The vision.EdgeDetector will be removed in a future release. Use
% the edge function with equivalent functionality instead.
% -----------------------------------------------------------------------
%
% HEDGE = vision.EdgeDetector returns an edge detection System object,
% HEDGE, that finds edges in an input image using Sobel, Prewitt,
% Roberts, or Canny algorithm.
%
% HEDGE = vision.EdgeDetector('PropertyName', PropertyValue, ...) returns
% an edge detection object, HEDGE, with each specified property set to
% the specified value.
%
% For Sobel, Prewitt and Roberts algorithms, the object finds edges in an
% input image by approximating the gradient magnitude of the image. The
% gradient is obtained as a result of convolving the image with the
% Sobel, Prewitt or Roberts kernel. For Canny algorithm, the object finds
% edges by looking for the local maxima of the gradient of the input
% image. It calculates the gradient using the derivative of a Gaussian
% filter. This algorithm is more robust to noise and more likely to
% detect true weak edges.
%
% Step method syntax:
%
% EDGES = step(HEDGE, IMG) finds the edges, EDGES, in input IMG using the
% specified algorithm when the BinaryImageOutputPort property is true.
% EDGES is a logical matrix with non-zero elements representing edge
% pixels and zero elements representing background pixels.
%
% [GV, GH] = step(HEDGE, IMG) finds the two gradient components, GV and
% GH, of the input IMG when the Method property is 'Sobel', 'Prewitt' or
% 'Roberts' and the GradientComponentOutputPorts property is true and the
% BinaryImageOutputPort property is false. If the Method property is
% 'Sobel' or 'Prewitt', GV is a matrix of gradient values in the vertical
% direction and GH is a matrix of gradient values in the horizontal
% direction. If the Method property is 'Roberts', GV represents the
% gradient component at 45 degree edge response and GH represents the
% gradient component at 135 degree edge response.
%
% [EDGES, GV, GH] = step(HEDGE, IMG) finds the edges, EDGES, and the two
% gradient components, GV and GH, of the input IMG when the Method
% property is 'Sobel', 'Prewitt' or 'Roberts' and both the
% BinaryImageOutputPort and GradientComponentOutputPorts properties are
% true.
%
% System objects may be called directly like a function instead of using
% the step method. For example, y = step(obj, x) and y = obj(x) are
% equivalent.
%
% EdgeDetector methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create edge detection object with same property values
% isLocked - Locked status (logical)
%
% EdgeDetector properties:
%
% Method - Edge detection algorithm
% BinaryImageOutputPort - Output the binary image
% GradientComponentOutputPorts - Output the gradient components
% ThresholdSource - Source of threshold value(s)
% Threshold - Threshold value(s)
% ThresholdScaleFactor - Multiplier to adjust value of
% automatic threshold
% EdgeThinning - Enables performing edge thinning
% NonEdgePixelsPercentage - Approximate percentage of weak and
% nonedge pixels
% GaussianFilterStandardDeviation - Standard deviation of Gaussian filter
%
% This System object supports fixed-point operations. For more
% information, type vision.EdgeDetector.helpFixedPoint.
%
% % EXAMPLE: Find the edges in peppers.png
% hedge = vision.EdgeDetector;
% img = rgb2gray(imread('peppers.png'));
% img1 = im2single(img);
% edges = step(hedge, img1);
% imshow(edges);
%
% See also EDGE
% Copyright 2004-2016 The MathWorks, Inc.
methods
function out=EdgeDetector
%EdgeDetector Find edges of objects in images
% -----------------------------------------------------------------------
% The vision.EdgeDetector will be removed in a future release. Use
% the edge function with equivalent functionality instead.
% -----------------------------------------------------------------------
%
% HEDGE = vision.EdgeDetector returns an edge detection System object,
% HEDGE, that finds edges in an input image using Sobel, Prewitt,
% Roberts, or Canny algorithm.
%
% HEDGE = vision.EdgeDetector('PropertyName', PropertyValue, ...) returns
% an edge detection object, HEDGE, with each specified property set to
% the specified value.
%
% For Sobel, Prewitt and Roberts algorithms, the object finds edges in an
% input image by approximating the gradient magnitude of the image. The
% gradient is obtained as a result of convolving the image with the
% Sobel, Prewitt or Roberts kernel. For Canny algorithm, the object finds
% edges by looking for the local maxima of the gradient of the input
% image. It calculates the gradient using the derivative of a Gaussian
% filter. This algorithm is more robust to noise and more likely to
% detect true weak edges.
%
% Step method syntax:
%
% EDGES = step(HEDGE, IMG) finds the edges, EDGES, in input IMG using the
% specified algorithm when the BinaryImageOutputPort property is true.
% EDGES is a logical matrix with non-zero elements representing edge
% pixels and zero elements representing background pixels.
%
% [GV, GH] = step(HEDGE, IMG) finds the two gradient components, GV and
% GH, of the input IMG when the Method property is 'Sobel', 'Prewitt' or
% 'Roberts' and the GradientComponentOutputPorts property is true and the
% BinaryImageOutputPort property is false. If the Method property is
% 'Sobel' or 'Prewitt', GV is a matrix of gradient values in the vertical
% direction and GH is a matrix of gradient values in the horizontal
% direction. If the Method property is 'Roberts', GV represents the
% gradient component at 45 degree edge response and GH represents the
% gradient component at 135 degree edge response.
%
% [EDGES, GV, GH] = step(HEDGE, IMG) finds the edges, EDGES, and the two
% gradient components, GV and GH, of the input IMG when the Method
% property is 'Sobel', 'Prewitt' or 'Roberts' and both the
% BinaryImageOutputPort and GradientComponentOutputPorts properties are
% true.
%
% System objects may be called directly like a function instead of using
% the step method. For example, y = step(obj, x) and y = obj(x) are
% equivalent.
%
% EdgeDetector methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create edge detection object with same property values
% isLocked - Locked status (logical)
%
% EdgeDetector properties:
%
% Method - Edge detection algorithm
% BinaryImageOutputPort - Output the binary image
% GradientComponentOutputPorts - Output the gradient components
% ThresholdSource - Source of threshold value(s)
% Threshold - Threshold value(s)
% ThresholdScaleFactor - Multiplier to adjust value of
% automatic threshold
% EdgeThinning - Enables performing edge thinning
% NonEdgePixelsPercentage - Approximate percentage of weak and
% nonedge pixels
% GaussianFilterStandardDeviation - Standard deviation of Gaussian filter
%
% This System object supports fixed-point operations. For more
% information, type vision.EdgeDetector.helpFixedPoint.
%
% % EXAMPLE: Find the edges in peppers.png
% hedge = vision.EdgeDetector;
% img = rgb2gray(imread('peppers.png'));
% img1 = im2single(img);
% edges = step(hedge, img1);
% imshow(edges);
%
% See also EDGE
end
function helpFixedPoint(in) %#ok<MANU>
%helpFixedPoint Display vision.EdgeDetector System object
% fixed-point information
% vision.EdgeDetector.helpFixedPoint displays information about
% fixed-point properties and operations of the
% vision.EdgeDetector System object.
end
function isInactivePropertyImpl(in) %#ok<MANU>
end
function loadObjectImpl(in) %#ok<MANU>
end
function saveObjectImpl(in) %#ok<MANU>
end
function setPortDataTypeConnections(in) %#ok<MANU>
end
end
methods (Abstract)
end
properties
%AccumulatorDataType Accumulator word- and fraction-length
% designations
% Specify the accumulator fixed-point data type as one of ['Same as
% first input' | {'Same as product'} | 'Custom']. This property is
% accessible when the Method property is not 'Canny'.
AccumulatorDataType;
%BinaryImageOutputPort Output the binary image
% Set this property to true to output the binary image after edge
% detection. When this property is set to true, the object will
% output a logical matrix. The nonzero elements of this matrix
% correspond to the edge pixels and the zero elements correspond to
% the background pixels. This property is accessible when the Method
% property is 'Sobel', 'Prewitt' or 'Roberts'. The default value for
% this property is true.
BinaryImageOutputPort;
%CustomAccumulatorDataType Accumulator word and fraction lengths
% Specify the accumulator fixed-point type as an auto-signed, scaled
% numerictype object. This property is accessible when the Method
% property is not 'Canny' and the AccumulatorDataType property is
% 'Custom'. The default value of this property is
% numerictype([],32,8).
%
% See also numerictype.
CustomAccumulatorDataType;
%CustomGradientDataType Gradient word and fraction lengths
% Specify the gradient components fixed-point type as an auto-signed,
% scaled numerictype object. This property is accessible when the
% Method property is not 'Canny', the GradientComponentOutputPorts
% property is true and the GradientDataType property is 'Custom'. The
% default value of this property is numerictype([],16,4).
%
% See also numerictype.
CustomGradientDataType;
%CustomProductDataType Product word and fraction lengths
% Specify the product fixed-point type as an auto-signed, scaled
% numerictype object. This property is accessible when the Method
% property is not 'Canny' and the ProductDataType property is
% 'Custom'. The default value of this property is
% numerictype([],32,8).
%
% See also numerictype.
CustomProductDataType;
%EdgeThinning Enables performing edge thinning
% Indicate whether edge thinning should be performed. Choosing to
% perform edge thinning requires additional processing time and
% resources. This property is accessible when the Method property is
% 'Sobel', 'Prewitt' or 'Roberts' and the BinaryImageOutputPort
% property is true. The default value of this property is false.
EdgeThinning;
%GaussianFilterStandardDeviation Standard deviation of Gaussian
% filter
% Specify the standard deviation of the Gaussian filter whose
% derivative is convolved with the input image. This property can be
% set to any positive scalar and the default value is 1. This
% property is accessible when the Method property is 'Canny'.
GaussianFilterStandardDeviation;
%GradientComponentOutputPorts Output the gradient components
% Set this property to true to output the gradient components after
% edge detection. When this property is set to true, and the Method
% property is set to 'Sobel' or 'Prewitt', this System object outputs
% the gradient components that correspond to the horizontal and
% vertical edge responses. When the Method property is set to
% 'Roberts', the System object outputs the gradient components that
% correspond to the 45 and 135 degree edge responses. Both
% BinaryImageOutputPort and GradientComponentOutputPorts properties
% cannot be false at the same time. The default value for this
% property is false.
GradientComponentOutputPorts;
%GradientDataType Gradient word- and fraction-length designations
% Specify the gradient components fixed-point data type as one of
% ['Same as accumulator' | {'Same as first input'} | 'Same as
% product' | 'Custom']. This property is accessible when the Method
% property is not 'Canny' and the GradientComponentOutputPorts
% property is true.
GradientDataType;
%Method Edge detection algorithm
% Specify the edge detection algorithm as one of [{'Sobel'} |
% 'Prewitt' | 'Roberts' | 'Canny'].
Method;
%NonEdgePixelsPercentage Approximate percentage of weak and nonedge
% pixels
% Specify the approximate percentage of weak edge and nonedge image
% pixels as a scalar between 0 and 100. The default value is 70. This
% property is applicable when the Method property is 'Canny' and the
% ThresholdSource is 'Auto'. This property is tunable.
NonEdgePixelsPercentage;
%OverflowAction Overflow action for fixed-point operations
% Specify the overflow action as one of [{'Wrap'} | 'Saturate']. This
% property is accessible when the Method property is not 'Canny'.
OverflowAction;
%ProductDataType Product word- and fraction-length designations
% Specify the product fixed-point data type as one of ['Same as first
% input' | {'Custom'}]. This property is accessible when the Method
% property is not 'Canny'.
ProductDataType;
%RoundingMethod Rounding method for fixed-point operations
% Specify the rounding method as one of ['Ceiling' | 'Convergent' |
% {'Floor'} | 'Nearest' |'Round' | 'Simplest' | 'Zero']. This
% property is accessible when the Method property is not 'Canny'.
RoundingMethod;
%Threshold Threshold value(s)
% Specify the threshold value as a scalar of MATLAB built-in numeric
% data type that is within the range of the input data when the
% Method property is 'Sobel', 'Prewitt' or 'Roberts'. Specify the
% threshold as two-element vector of low and high values that define
% the weak and strong edges when the Method property is 'Canny'. The
% default value is [0.25 0.6] when the Method property is 'Canny' or
% 20 otherwise. This property is accessible when the ThresholdSource
% property is 'Property'. This property is tunable.
Threshold;
%ThresholdScaleFactor Multiplier to adjust value of automatic
% threshold
% Specify multiplier that is used to adjust calculation of automatic
% threshold as a scalar MATLAB built-in numeric data type. The
% default value is 4. This property is accessible when the Method
% property is 'Sobel', 'Prewitt' or 'Roberts' and the ThresholdSource
% property is 'Auto'. This property is tunable.
ThresholdScaleFactor;
%ThresholdSource Source of threshold value
% Specify how to determine threshold as one of [{'Auto'} | 'Property'
% | 'Input port']. This property is accessible when the Method
% property is 'Canny'. This property is also accessible when the
% Method property is 'Sobel', 'Prewitt' or 'Roberts' and the
% BinaryImageOutputPort property is true.
ThresholdSource;
end
end