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Detect & Present movements. Mammal Visual system

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Detect & Present movements. Mammal Visual system


Nikolay S. (view profile)


24 Oct 2011 (Updated )

This function tracks and presents moving regions in real time from still camera or file.

showMovements(inVideo, moveTresh, strelOpen, strelClose)
function showMovements(inVideo, moveTresh, strelOpen, strelClose)
%% function showMovements(inVideo, moveTresh, strelOpen, strelClose)
% This function tracks and presents moving regions in real time a video
% filmed by a still camera, or on a video file stred on the computer
%% Syntax
%  showMovements(inVideo);
%  showMovements(inVideo, moveTresh);
%  showMovements(inVideo, moveTresh, strelOpen);
%  showMovements(inVideo, moveTresh, strelOpen, strelClose);
%% Description
%  This functions is the main applications function. It presents a figure
%  with only moving regions of the video. The user can control signal
%  source (a file or a device on the computer) several parameters, to
%  achive the presentation of regions he is interested in. This function
%  can be though of as a mammal vision system simulation (some mammals,
%  like dogs, see only object that move). My son likes to play the
%  following game: first he is hiding (he stays still, to get a totally
%  dark scrren), and the he moves, and shown by the application.
%% Input arguments (defaults exist):
%   inVideo- input video file name or a video device, or none, and then
%       user selects input via dialog menus.
%   moveTresh- used to deetct movements. Pixels with value above this
%       treshold are assumed to include movements. 
%   strelOpen- a structuring element, and integer value used to define
%       a structuring element dimentions, or a matrix of logicals used to
%       define the presneted ROI dimentions. In other worlds defines the
%       area around detected movements to be presented. Larger value will
%       resul in larger region.
%   strelClose- a structuring element, and integer value used to define
%       a structuring element dimentions, or a matrix of logicals. Those
%       define the speed of "aging", or hsitorical data influencue on
%       current figure. It defines how the ROI of previous frame infleuemce
%       ROI of current frame. Larger value will result in fatser aging- old
%       ROI data will be removed fatser. Small value will result in slow
%       "aging"- areas with movements in previous frames, will be preserved
%       and presenetd in longer period.
%% Output arguments
%   None. Movements are presenetd on a figure.
%% Issues & Comments 
% Camera is assumed to be still
% In case this function will be demnaded by the aouiebnce, I'll add a GUI,
% so the structuring element can be changed during run time. At this point
% the goal is to build a simple function with nice results.
%% Example
% inVideo='xylophone.mpg';
% moveTresh=30;
% strelOpen=2;
% strelClose=2;
% implay(inVideo);
% showMovements(inVideo, moveTresh, strelOpen, strelClose);
%% See also
%   markMovesInCamera
%   markMovesInVideo
%% Revision history
% First version: Nikolay S. 2011-10-23.
% Last update:   Nikolay S. 2011-10-24.
% *List of Changes:*

%% Default parameters
if nargin<4
    if nargin<3
        if nargin<2
            if nargin==0

if exist('inVideo','var')~=1 || isempty(inVideo)
    % let the user choose file/video source via a dialog menu
    inputSourceButton = questdlg('Camera of Video file input?','Video data source','Video file','USB camera','Video file'); 
    switch (inputSourceButton)
        case('Video file')
            % in case of file- find it via files browser
            videoFormats= VideoReader.getFileFormats();
            FilterSpec={cat(2, 'Video Files (', videosFilesFilter, ')');};

            [filename, pathname] = uigetfile( FilterSpec,...
                'Pick a video file to track movements in');
        case('USB camera')
            % in case of camera- first get a list of avalible devices
            [adaptorsWithDevices, deviceNames]=findInstalledDevices;
            pause(1); % Some Windows users reported a problem here
            % allow the user to pick the device to be used
            if isempty(deviceNames) || iscell(deviceNames) && isempty(deviceNames{1})
                    'Important- when running this function for the first time with Matlab 2013 and later,\n',...
                    'use the Support Package Installer to install your camera Video Interface.\n',...
                    'For most cases that would be the OS Generic Video Interface.');
                error('No Image Acquisition adaptors found:showMovements');
            [iInputDevice, ~] = listdlg('PromptString', 'Select format:',...
                'SelectionMode', 'single', 'ListString', deviceNames);

            %% Find adaptor to support the chosen device
            nAdaptors = length(adaptorsWithDevices);
            for iAdaptor=1:nAdaptors
                %% Obtaining Device Information
                % Calling |imaqInfoHW| with an adaptor name returns a structure that provides
                % information on all accessible image acquisition devices.
                InfoHW = imaqhwinfo(adaptorsWithDevices{iAdaptor});
                for iDevice=1:nDevice
                    if strcmpi( inputDevice, InfoHW.DeviceInfo(iDevice).DeviceName);
                        supportedFormats= InfoHW.DeviceInfo.SupportedFormats;
                    if exist('inputAdaptor','var')==1
                end % for iDevice=1:nDevice
            end % for iAdaptor=1:nAdaptors
            % Allow the user to pick the desired vidoe format (color space
            % & resolution)
            [iInputFormat, v] = listdlg('PromptString', 'Select format:',...
                'SelectionMode', 'single', 'ListString',supportedFormats);
            % Create an appropriate vidoe input
            inVideo=videoinput(inputAdaptor, deviceID, inputFormat);
    end % switch (inputSourceButton)

%% Call the correct function, accourding to inVideo (file or a device)
if strcmpi(class(inVideo),'videoinput')
    markMovesInCamera(inVideo, moveTresh, strelOpen, strelClose);
elseif exist(inVideo,'file')==2
    markMovesInVideo(inVideo, moveTresh, strelOpen, strelClose);
    'Input video source or file name is missing.');

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