gusucode.com > vision工具箱matlab源码程序 > vision/+vision/en/HoughLines.m
classdef HoughLines< matlab.system.SFunSystem
%HoughLines Find Cartesian coordinates of lines described by rho and theta pairs
% HHoughLines = vision.HoughLines returns a Hough lines System object,
% HHoughLines, that finds Cartesian coordinates of lines that are
% described by rho and theta pairs. The object inputs are the theta and
% rho values of lines and a reference image. The object outputs the [x y]
% coordinates of the intersections between the lines and two of the
% reference image boundary lines. The boundary lines are the left and
% right vertical boundaries and the top and bottom horizontal boundaries
% of the reference image.
%
% HHoughLines = vision.HoughLines('PropertyName', PropertyValue, ...)
% returns a Hough lines object, HHoughLines, with each specified property
% set to the specified value.
%
% Step method syntax:
%
% PTS = step(HHoughLines, THETA, RHO, REFIMG) outputs the [x y]
% coordinates of the intersections between the lines described by THETA
% and RHO and two of the reference image boundary lines.
%
% 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.
%
% HoughLines methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create Hough lines object with same property values
% isLocked - Locked status (logical)
%
% HoughLines properties:
%
% SineComputation - How to calculate sine values used to find
% intersections of lines
% ThetaResolution - Spacing of the theta-axis
%
% This System object supports fixed-point operations when the
% SineComputation property is 'Table lookup'. For more information, type
% vision.HoughLines.helpFixedPoint.
%
% % EXAMPLE: Use hough lines to detect the longest line in an image.
%
% I = imread('circuit.tif');
%
% % Use the EdgeDetection System object to find edges in the intensity
% % image. This step outputs a binary image required by the
% % HoughTransform System object and improves the efficiency of the
% % HoughLines System object.
% hedge = vision.EdgeDetector;
% hhoughtrans = vision.HoughTransform(pi/360, ...
% 'ThetaRhoOutputPort', true);
% hfindmax = vision.LocalMaximaFinder(1, ...
% 'HoughMatrixInput', true);
% hhoughlines = vision.HoughLines('SineComputation', ...
% 'Trigonometric function');
%
% % Find the edges in the intensity image
% BW = step(hedge, I);
% % Run the edge output through the transform
% [ht, theta, rho] = step(hhoughtrans, BW);
% % Find the location of the maximum value in the Hough matrix.
% idx = step(hfindmax, ht);
% % Find the longest line.
% linepts = step(hhoughlines, theta(idx(1)-1), rho(idx(2)-1), I);
%
% % View the image superimposed with the longest line.
% imshow(I); hold on;
% line(linepts([1 3])-1, linepts([2 4])-1,'color',[1 1 0]);
%
% See also HOUGH, HOUGHPEAKS, HOUGHLINES, vision.HoughLines.helpFixedPoint.
% Copyright 2008-2016 The MathWorks, Inc.
methods
function out=HoughLines
%HoughLines Find Cartesian coordinates of lines described by rho and theta pairs
% HHoughLines = vision.HoughLines returns a Hough lines System object,
% HHoughLines, that finds Cartesian coordinates of lines that are
% described by rho and theta pairs. The object inputs are the theta and
% rho values of lines and a reference image. The object outputs the [x y]
% coordinates of the intersections between the lines and two of the
% reference image boundary lines. The boundary lines are the left and
% right vertical boundaries and the top and bottom horizontal boundaries
% of the reference image.
%
% HHoughLines = vision.HoughLines('PropertyName', PropertyValue, ...)
% returns a Hough lines object, HHoughLines, with each specified property
% set to the specified value.
%
% Step method syntax:
%
% PTS = step(HHoughLines, THETA, RHO, REFIMG) outputs the [x y]
% coordinates of the intersections between the lines described by THETA
% and RHO and two of the reference image boundary lines.
%
% 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.
%
% HoughLines methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create Hough lines object with same property values
% isLocked - Locked status (logical)
%
% HoughLines properties:
%
% SineComputation - How to calculate sine values used to find
% intersections of lines
% ThetaResolution - Spacing of the theta-axis
%
% This System object supports fixed-point operations when the
% SineComputation property is 'Table lookup'. For more information, type
% vision.HoughLines.helpFixedPoint.
%
% % EXAMPLE: Use hough lines to detect the longest line in an image.
%
% I = imread('circuit.tif');
%
% % Use the EdgeDetection System object to find edges in the intensity
% % image. This step outputs a binary image required by the
% % HoughTransform System object and improves the efficiency of the
% % HoughLines System object.
% hedge = vision.EdgeDetector;
% hhoughtrans = vision.HoughTransform(pi/360, ...
% 'ThetaRhoOutputPort', true);
% hfindmax = vision.LocalMaximaFinder(1, ...
% 'HoughMatrixInput', true);
% hhoughlines = vision.HoughLines('SineComputation', ...
% 'Trigonometric function');
%
% % Find the edges in the intensity image
% BW = step(hedge, I);
% % Run the edge output through the transform
% [ht, theta, rho] = step(hhoughtrans, BW);
% % Find the location of the maximum value in the Hough matrix.
% idx = step(hfindmax, ht);
% % Find the longest line.
% linepts = step(hhoughlines, theta(idx(1)-1), rho(idx(2)-1), I);
%
% % View the image superimposed with the longest line.
% imshow(I); hold on;
% line(linepts([1 3])-1, linepts([2 4])-1,'color',[1 1 0]);
%
% See also HOUGH, HOUGHPEAKS, HOUGHLINES, vision.HoughLines.helpFixedPoint.
end
function helpFixedPoint(in) %#ok<MANU>
%helpFixedPoint Display vision.HoughLines System object fixed-point
% information
% vision.HoughLines.helpFixedPoint displays information about
% fixed-point properties and operations of the vision.HoughLines
% System object.
end
function isInactivePropertyImpl(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
% product'} | 'Custom']. This property is applicable when the
% SineComputation property is 'Table lookup'.
AccumulatorDataType;
%CustomAccumulatorDataType Accumulator word and fraction lengths
% Specify the accumulator fixed-point type as an auto-signed scaled
% numerictype object. This property is applicable when the
% SineComputation property is 'Table lookup', and the
% AccumulatorDataType property is 'Custom'. The default value of this
% property is numerictype([],32,16).
%
% See also numerictype.
CustomAccumulatorDataType;
%CustomProductDataType Product word and fraction lengths
% Specify the product fixed-point type as an auto-signed scaled
% numerictype object. This property is applicable when the
% SineComputation property is 'Table lookup', and the ProductDataType
% property is 'Custom'. The default value of this property is
% numerictype([],32,16).
%
% See also numerictype.
CustomProductDataType;
%CustomSineTableDataType Sine table word and fraction lengths
% Specify the sine table fixed-point type as an auto-signed unscaled
% numerictype object. This property is applicable when the
% SineComputation property is 'Table lookup', and the
% SineTableDataType property is 'Custom'. The default value of this
% property is numerictype([],16).
%
% See also numerictype.
CustomSineTableDataType;
%OverflowAction Overflow action for fixed-point operations
% Specify the overflow action as one of [{'Wrap'} | 'Saturate']. This
% property is applicable when the SineComputation property is 'Table
% lookup'.
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 applicable when the
% SineComputation property is 'Table lookup'.
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 applicable when the SineComputation property is 'Table
% lookup'.
RoundingMethod;
%SineComputation How to calculate sine values used to find
% intersections of lines
% Specify how to calculate sine values which is used to find
% intersection of lines as one of ['Trigonometric function' | {'Table
% lookup'}]. If this property is set to 'Trigonometric function', the
% object computes sine and cosine values it needs to calculate the
% intersections of the lines. If it is set to 'Table lookup', the
% object computes and stores the trigonometric values it needs to
% calculate the intersections of the lines in a table and uses the
% table for each step call. In this case, the object requires extra
% memory. For floating-point inputs, this property must be set to
% 'Trigonometric function'. For fixed-point inputs, the property must
% be set to 'Table lookup'.
SineComputation;
%SineTableDataType Sine table word- and fraction-length designations
% Specify the sine table fixed-point data type as a constant property
% always set to 'Custom'. This property is applicable when the
% SineComputation property is 'Table lookup'.
SineTableDataType;
%ThetaResolution Spacing of the theta-axis
% Specify the spacing of the theta-axis. This property is applicable
% when the SineComputation property is 'Table lookup'.
ThetaResolution;
end
end