gusucode.com > vision工具箱matlab源码程序 > vision/+vision/en/OpticalFlow.m
classdef OpticalFlow< matlab.System
%OpticalFlow Estimate object velocities
% -----------------------------------------------------------------------
% The vision.OpticalFlow will be removed in a future release. Use the
% opticalFlowHS, opticalFlowLK, or opticalFlowLKDoG function with
% equivalent functionality instead.
% -----------------------------------------------------------------------
%
% Use vision.OpticalFlow when you need to process fixed-point data with
% Lucas-Kanade (Difference filter) method. For all other applications,
% use the opticalFlowHS, opticalFlowLK, or opticalFlowLKDoG function.
%
% HOF = vision.OpticalFlow returns an optical flow System object, HOF,
% that estimates the direction and speed of object motion from one image
% to another, or from one video frame to another.
%
% HOF = vision.OpticalFlow('PropertyName', PropertyValue, ...) returns an
% optical flow System object, HOF, with each specified property set to
% the specified value.
%
% Step method syntax:
%
% VSQ = step(HOF, I) computes the optical flow of input image I from one
% video frame to another, and returns VSQ as a matrix of velocity
% magnitudes.
%
% V = step(HOF, I) computes the optical flow of input image I from one
% video frame to another, and returns V as a complex matrix of horizontal
% and vertical components, when the OutputValue property is 'Horizontal
% and vertical components in complex form'.
%
% [...] = step(HOF, I1, I2) computes the optical flow of the input image
% I1, using I2 as a reference frame, when the ReferenceFrameSource
% property is 'Input port'.
%
% [..., IMV] = step(HOF, I) outputs the delayed input image, IMV. The
% delay is equal to the latency introduced by the computation of the
% motion vectors. This property is visible when the Method property is
% 'Lucas-Kanade', the TemporalGradientFilter property is 'Derivative of
% Gaussian', and the MotionVectorImageOutputPort property is 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.
%
% OpticalFlow methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create optical flow object with same property values
% isLocked - Locked status (logical)
%
% OpticalFlow properties:
%
% Method - Algorithm used to compute
% optical flow
% ReferenceFrameSource - Source of the reference
% frame used for the optical
% flow calculation
% ReferenceFrameDelay - Number of frames between
% reference and current frame
% Smoothness - Term expressing expected
% smoothness of optical flow
% IterationTerminationCondition - Condition to stop iterative
% solution computation
% MaximumIterationCount - Maximum number of iterations
% to perform
% VelocityDifferenceThreshold - Velocity difference
% threshold to stop
% computation
% OutputValue - Form of velocity output
% TemporalGradientFilter - Type of temporal gradient
% filter
% BufferedFramesCount - Number of frames to buffer
% for temporal smoothing
% ImageSmoothingFilterStandardDeviation - Standard deviation for image
% smoothing filter
% GradientSmoothingFilterStandardDeviation - Standard deviation for
% gradient smoothing filter
% DiscardIllConditionedEstimates - Discard normal flow
% estimates when constraint
% equation is ill-conditioned
% MotionVectorImageOutputPort - Return image corresponding
% to motion vectors
% NoiseReductionThreshold - Threshold for noise
% reduction
%
% This System object supports fixed-point operations when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter property is
% 'Difference filter [-1 1]'. For more information, type
% vision.OpticalFlow.helpFixedPoint.
%
% % EXAMPLE: Track cars using optical flow.
% hvfr = vision.VideoFileReader('viptraffic.avi', ...
% 'ImageColorSpace', 'Intensity', ...
% 'VideoOutputDataType', 'uint8');
% hof = vision.OpticalFlow('ReferenceFrameDelay', 1);
% hof.OutputValue = 'Horizontal and vertical components in complex form';
% hvp = vision.VideoPlayer('Name', 'Motion Vector');
% while ~isDone(hvfr)
% frame = step(hvfr);
% im = im2single(frame); % convert the image to 'single' precision
% of = step(hof, im); % compute optical flow for the video
% lines = videooptflowlines(of, 20); % generate coordinate points
% out = insertShape(im, 'Line', lines, ...
% 'Color', 'white'); % draw lines to indicate flow
% step(hvp, out); % view in video player
% end
% release(hvp);
% release(hvfr);
%
% See also insertShape, vision.Pyramid, vision.OpticalFlow.helpFixedPoint,
% opticalFlowHS, opticalFlowLK, opticalFlowLKDoG.
% Copyright 2004-2016 The MathWorks, Inc.
methods
function out=OpticalFlow
%OpticalFlow Estimate object velocities
% -----------------------------------------------------------------------
% The vision.OpticalFlow will be removed in a future release. Use the
% opticalFlowHS, opticalFlowLK, or opticalFlowLKDoG function with
% equivalent functionality instead.
% -----------------------------------------------------------------------
%
% Use vision.OpticalFlow when you need to process fixed-point data with
% Lucas-Kanade (Difference filter) method. For all other applications,
% use the opticalFlowHS, opticalFlowLK, or opticalFlowLKDoG function.
%
% HOF = vision.OpticalFlow returns an optical flow System object, HOF,
% that estimates the direction and speed of object motion from one image
% to another, or from one video frame to another.
%
% HOF = vision.OpticalFlow('PropertyName', PropertyValue, ...) returns an
% optical flow System object, HOF, with each specified property set to
% the specified value.
%
% Step method syntax:
%
% VSQ = step(HOF, I) computes the optical flow of input image I from one
% video frame to another, and returns VSQ as a matrix of velocity
% magnitudes.
%
% V = step(HOF, I) computes the optical flow of input image I from one
% video frame to another, and returns V as a complex matrix of horizontal
% and vertical components, when the OutputValue property is 'Horizontal
% and vertical components in complex form'.
%
% [...] = step(HOF, I1, I2) computes the optical flow of the input image
% I1, using I2 as a reference frame, when the ReferenceFrameSource
% property is 'Input port'.
%
% [..., IMV] = step(HOF, I) outputs the delayed input image, IMV. The
% delay is equal to the latency introduced by the computation of the
% motion vectors. This property is visible when the Method property is
% 'Lucas-Kanade', the TemporalGradientFilter property is 'Derivative of
% Gaussian', and the MotionVectorImageOutputPort property is 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.
%
% OpticalFlow methods:
%
% step - See above description for use of this method
% release - Allow property value and input characteristics changes
% clone - Create optical flow object with same property values
% isLocked - Locked status (logical)
%
% OpticalFlow properties:
%
% Method - Algorithm used to compute
% optical flow
% ReferenceFrameSource - Source of the reference
% frame used for the optical
% flow calculation
% ReferenceFrameDelay - Number of frames between
% reference and current frame
% Smoothness - Term expressing expected
% smoothness of optical flow
% IterationTerminationCondition - Condition to stop iterative
% solution computation
% MaximumIterationCount - Maximum number of iterations
% to perform
% VelocityDifferenceThreshold - Velocity difference
% threshold to stop
% computation
% OutputValue - Form of velocity output
% TemporalGradientFilter - Type of temporal gradient
% filter
% BufferedFramesCount - Number of frames to buffer
% for temporal smoothing
% ImageSmoothingFilterStandardDeviation - Standard deviation for image
% smoothing filter
% GradientSmoothingFilterStandardDeviation - Standard deviation for
% gradient smoothing filter
% DiscardIllConditionedEstimates - Discard normal flow
% estimates when constraint
% equation is ill-conditioned
% MotionVectorImageOutputPort - Return image corresponding
% to motion vectors
% NoiseReductionThreshold - Threshold for noise
% reduction
%
% This System object supports fixed-point operations when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter property is
% 'Difference filter [-1 1]'. For more information, type
% vision.OpticalFlow.helpFixedPoint.
%
% % EXAMPLE: Track cars using optical flow.
% hvfr = vision.VideoFileReader('viptraffic.avi', ...
% 'ImageColorSpace', 'Intensity', ...
% 'VideoOutputDataType', 'uint8');
% hof = vision.OpticalFlow('ReferenceFrameDelay', 1);
% hof.OutputValue = 'Horizontal and vertical components in complex form';
% hvp = vision.VideoPlayer('Name', 'Motion Vector');
% while ~isDone(hvfr)
% frame = step(hvfr);
% im = im2single(frame); % convert the image to 'single' precision
% of = step(hof, im); % compute optical flow for the video
% lines = videooptflowlines(of, 20); % generate coordinate points
% out = insertShape(im, 'Line', lines, ...
% 'Color', 'white'); % draw lines to indicate flow
% step(hvp, out); % view in video player
% end
% release(hvp);
% release(hvfr);
%
% See also insertShape, vision.Pyramid, vision.OpticalFlow.helpFixedPoint,
% opticalFlowHS, opticalFlowLK, opticalFlowLKDoG.
end
function getNumInputsImpl(in) %#ok<MANU>
end
function getNumOutputsImpl(in) %#ok<MANU>
end
function helpFixedPoint(in) %#ok<MANU>
%helpFixedPoint Display vision.OpticalFlow System object fixed-point ...
% information
% vision.OpticalFlow.helpFixedPoint displays information about
% fixed-point properties and operations of the vision.OpticalFlow
% System object.
end
function isInactivePropertyImpl(in) %#ok<MANU>
end
function isInputComplexityLockedImpl(in) %#ok<MANU>
end
function isInputSizeLockedImpl(in) %#ok<MANU>
end
function isOutputComplexityLockedImpl(in) %#ok<MANU>
end
function loadObjectImpl(in) %#ok<MANU>
end
function processTunedPropertiesImpl(in) %#ok<MANU>
end
function resetImpl(in) %#ok<MANU>
end
function saveObjectImpl(in) %#ok<MANU>
end
function setupImpl(in) %#ok<MANU>
% cache state in private property for efficiency
end
function stepImpl(in) %#ok<MANU>
end
function validateInputsImpl(in) %#ok<MANU>
% Input validation
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 accessible when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Difference filter [-1 1]'.
AccumulatorDataType;
%BufferedFramesCount Number of frames to buffer for temporal smoothing
% Specify the number of frames to buffer for temporal smoothing as an
% odd integer between 3 and 31, both inclusive. The default value of
% this property is 3. This property determines characteristics such
% as the standard deviation and the number of filter coefficients of
% the Gaussian filter used to perform temporal filtering. This
% property is accessible when the Method property is
% 'Lucas-Kanade' and the TemporalGradientFilter is 'Derivative of
% Gaussian'.
BufferedFramesCount;
%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 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Difference filter [-1 1]'. This property is applicable when the
% AccumulatorDataType property is 'Custom'. The default value of this
% property is numerictype([],32,20).
%
% See also numerictype.
CustomAccumulatorDataType;
%CustomGradientDataType Gradient word and fraction lengths
% Specify the gradient fixed-point type as an auto-signed, scaled
% numerictype object. This property is accessible when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Difference filter [-1 1]'. This property is applicable when the
% GradientDataType property is 'Custom'. The default value of this
% property is numerictype([],32,20).
%
% See also numerictype.
CustomGradientDataType;
%CustomOutputDataType Output word and fraction lengths
% Specify the output fixed-point type as an auto-signed scaled
% numerictype object. This property is accessible when the Method
% property is 'Lucas-Kanade', the TemporalGradientFilter is
% 'Difference filter [-1 1]' and the OutputDataType property is
% 'Custom'. The default value of this property is
% numerictype([],32,20).
%
% See also numerictype.
CustomOutputDataType;
%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 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Difference filter [-1 1]'. This property is applicable when the
% ProductDataType property is 'Custom'. The default value of this
% property is numerictype([],32,20).
%
% See also numerictype.
CustomProductDataType;
%CustomThresholdDataType Threshold word and fraction lengths
% Specify the threshold fixed-point type as an auto-signed
% numerictype object. This property is accessible when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Difference filter [-1 1]'. This property is applicable when the
% ThresholdDataType property is 'Custom'. The default value of this
% property is numerictype([],16,12).
%
% See also numerictype.
CustomThresholdDataType;
%DiscardIllConditionedEstimates Discard normal flow estimates when
% constraint equation is ill-conditioned
% Set this property to true if the motion vector should be set to 0
% when the optical flow constraint equation is ill-conditioned. The
% default value of this property is false. This property is
% accessible when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Derivative of Gaussian'. This property
% is tunable.
DiscardIllConditionedEstimates;
%GradientDataType Gradient word- and fraction-length designations
% Specify the gradient fixed-point data type as one of [{'Same as
% accumulator'} | 'Same as product' | 'Custom']. This property is
% accessible when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Difference filter [-1 1]'.
GradientDataType;
%GradientSmoothingFilterStandardDeviation Standard deviation for
% gradient smoothing filter
% Specify the standard deviation for the filter used to smooth the
% spatiotemporal image gradient components as a scalar number greater
% than 0. The default value of this property is 1. This property is
% accessible when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Derivative of Gaussian'.
GradientSmoothingFilterStandardDeviation;
%ImageSmoothingFilterStandardDeviation Standard deviation for image
% smoothing filter
% Specify the standard deviation for the Gaussian filter used to
% smooth the image using spatial filtering as a scalar number greater
% than 0. The default value of this property is 1.5. This property is
% accessible when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Derivative of Gaussian'.
ImageSmoothingFilterStandardDeviation;
%IterationTerminationCondition Condition to stop iterative solution
% computation
% Specify when the optical flow iterative solution should stop as one
% of [{'Maximum iteration count'} | 'Velocity difference threshold'
% | 'Either']. This property is accessible when the Method property
% is 'Horn-Schunck'.
IterationTerminationCondition;
%MaximumIterationCount Maximum number of iterations to perform
% Specify the maximum number of iterations to perform in the optical
% flow iterative solution computation as a scalar integer value
% greater than 0. The default value of this property is 10. This
% property is accessible when the Method property is 'Horn-Schunck'
% and the IterationTerminationCondition property is either 'Maximum
% iteration count' or 'Either'. This property is tunable.
MaximumIterationCount;
%Method Algorithm used to compute optical flow
% Specify the algorithm to compute the optical flow as one of
% [ {'Horn-Schunck'} | 'Lucas-Kanade' ].
Method;
%MotionVectorImageOutputPort Return image corresponding to motion
% vectors
% Set this property to true to output the image that corresponds to
% the motion vector being output by the object. The default value of
% this property is false. This property is accessible when the Method
% property is 'Lucas-Kanade' and the TemporalGradientFilter is
% 'Derivative of Gaussian'.
MotionVectorImageOutputPort;
%NoiseReductionThreshold Threshold for noise reduction
% Specify the motion threshold between each image or video frame as a
% scalar number greater than 0. The higher the number, the less small
% movements impact the optical flow calculation. The default value of
% this property is 0.0039. This property is accessible when the
% Method property is 'Lucas-Kanade'. This property is tunable.
NoiseReductionThreshold;
%OutputDataType Output word- and fraction-length designations
% Specify the output fixed-point data type as 'Custom'. This property
% is accessible when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Difference filter [-1 1]'.
OutputDataType;
%OutputValue Form of velocity output
% Specify the velocity output as one of [ {'Magnitude-squared'} |
% 'Horizontal and vertical components in complex form' ].
OutputValue;
%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 'Lucas-Kanade'
% and the TemporalGradientFilter is 'Difference filter [-1 1]'.
OverflowAction;
%ProductDataType Product word- and fraction-length designations
% Specify the product fixed-point data type as 'Custom'. This
% property is accessible when the Method property is 'Lucas-Kanade'
% and the TemporalGradientFilter is 'Difference filter [-1 1]'.
ProductDataType;
%ReferenceFrameDelay Number of frames between reference frame and
% current frame
% Specify the number of frames between the reference and current
% frame as a scalar integer value greater than 0. The default value
% of this property is 1. This property is accessible when the
% ReferenceFrameSource property is 'Property'.
ReferenceFrameDelay;
%ReferenceFrameSource Source of the reference frame used for the
% optical flow calculation
% Specify computing optical flow between one of [ {'Property'} |
% 'Input port' ]. When this property is set to 'Property', the
% ReferenceFrameDelay property is used to determine a previous frame
% with which to compare. When this property is set to 'Input Port',
% an input image should be supplied for comparison. This property is
% accessible when the Method property is 'Horn-Schunck'. This
% property is also accessible when the Method property is
% 'Lucas-Kanade' and the TemporalGradientFilter is 'Difference filter
% [-1 1]'.
ReferenceFrameSource;
%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 'Lucas-Kanade'
% and the TemporalGradientFilter is 'Difference filter [-1 1]'.
RoundingMethod;
%Smoothness Term expressing expected smoothness of optical flow
% Specify the smoothness factor as a positive scalar number. If the
% relative motion between the two images or video frames is large,
% specify a large positive scalar value. If the relative motion is
% small, specify a small positive scalar value. The default value of
% this property is 1. This property is accessible when the Method
% property is 'Horn-Schunck'. This property is tunable.
Smoothness;
%TemporalGradientFilter Temporal gradient filter used by Lucas-Kanade
% algorithm
% Specify the temporal gradient filter used by the Lucas-Kanade
% algorithm as one of [{'Difference filter [-1 1]'} | 'Derivative of
% Gaussian']. This property is accessible when the Method property
% is 'Lucas-Kanade'.
TemporalGradientFilter;
%ThresholdDataType Threshold word- and fraction-length designations
% Specify the threshold fixed-point data type as one of [{'Same word
% length as first input'} | 'Custom']. This property is accessible
% when the Method property is 'Lucas-Kanade' and the
% TemporalGradientFilter is 'Difference filter [-1 1]'.
ThresholdDataType;
%VelocityDifferenceThreshold Velocity difference threshold to stop
% computation
% Specify the velocity difference threshold to stop the optical flow
% iterative solution computation as a scalar number greater than 0.
% The default value of this property is eps. This property is
% accessible when the Method property is 'Horn-Schunck' and the
% IterationTerminationCondition property is either 'Maximum iteration
% count' or 'Either'. This property is tunable.
VelocityDifferenceThreshold;
end
end