For object tracking of many objects.....

Dear Sir,

I am working now on "Object Tracking Project"... I found this website on Mathworks http://www.mathworks.it/it/help/vision/examples/motion-based-multiple-object-tracking.html and this website help me to know some information that I must know them about each object...This Program required from me to make this Function "tracks = initializeTracks" BUT... I found problem when I go to use this Function " predictNewLocationsOfTracks ()" where I don't know the "Length of tracks" so I find ERROR in the "FOR LOOP" in this function..... I would like to know "How can I know the number of tracks??"

Thank you very much

Have Great and Fantastic day

Answer 1

[Walter Roberson]

The example has all the necessary code, including initializeTracks.

Please note that at the very end of the example, there is an "end" right above the "Was this topic helpful?". That "end" is needed. You need to put all the routines in the same file, and the structure should look like

function multiObjectTracking()
  [... ] code here

    function obj = setupSystemObjects()
      [...] code here
    end

    function tracks = initializeTracks()
       [...] code here
    end

    [...] more function / end pairs here

end     %the stray "end" from the bottom of the page

When all the function/end pairs are created like this, "tracks" will become a variable that is shared with all of the routines.

[Mohamed Elwakdy]

Dear Walter,

Thank you very much on your interesting....

I made such as you required from me but I have the same problem.. "length (tracks) = 0" in "predictNewLocationsOfTracks (tracks)" Function and "nTracks = 0" in function [assignments, unassignedTracks, unassignedDetections] = detectionToTrackAssignment(tracks,centroids)... I would like to know if there is anything that I can do it for solving this problem....

Thank you very much

Have Great and Fantastic Day

[Mohamed Elwakdy]

Dear Walter,

I think my problem in this code that the knowing of "legnth (tracks)"... if I have this information that I think that my problem will be solved....

Thank you very much

[Walter Roberson]

length(tracks) is intended to start out as 0.

I believe that it detects objects to be tracked as it goes.

[Mohamed Elwakdy]

Dear Walter,

Thank you very much on your interesting....

The program is run already but I didn,t see the "labels" or anything indicates to the tracks in the "displays" of the Video or forground mask.... I think that the problem is the value of "length(tracks)" and "nTracks" = 0 in all of frames.... I think that this is happened because in this function " "predictNewLocationsOfTracks (tracks)":

for i = 1: length (tracks) % length (tracks) = 0 already so the value of "nTracks" is always with "0" in all of frames... This is the problem.... I would like to help me in solving this problem....

Thank you very much

[Walter Roberson]

No, createNewTracks() turns detected objects into tracks. The program detects and tracks objects as it goes, and even deletes objects that have gone away for too long. It might take a few steps before a detected object is promoted to be a "track".

[Mohamed Elwakdy]

Dear Walter,

Thank you very much on your interesting...

In my code, I wanted to recognize on the tracks of three objects so I certain their positions (left, bottom, width, height) through I put them inside "3 boxes"... I have the problem to display tracks that have been visible, display predicted bounding box or create labels for objects in "displayTrackingResults" function after I made run of the code where I noted that the program isn't going to the " if ~isempty(reliableTracks)" in "displayTrackingResults" function... when I tried to make some changes by putting "tracks1= tracks" in "createNewTracks" function, change the "minVisibleCount" with "low" value in the "function displayTrackingResults(frame, mask, tracks1,obj)", I noted that the program "run" after if statement "if ~isempty(reliableTracks)" but it give me this error:

Error using insertObjectAnnotation>crossCheckInputs (line 247) The number of columns in POSITION must be 4 for the 'rectangle' shape, or 3 for the 'circle' shape.

Error in insertObjectAnnotation>validateAndParseInputs (line 161) crossCheckInputs(shape, position, numLabels, color, textColor);

Error in insertObjectAnnotation (line 99) [RGB, shape, position, label, color, textColor, ...

Error in displayTrackingResults (line 67) frame = insertObjectAnnotation(frame, 'rectangle',bboxes, labels);

Error in Demo (line 272) displayTrackingResults(frame, mask, tracks1,obj);

I would like you to help me to fix this error to have the ability to see the tracks that have been visibl, display predicted bounding box or create labels for objects in "displayTrackingResults"....

Thank you very much

Have Great and Fantastic Day

Mohamed Elwakdy