please help me ! Unrecognized function or variable 'hasFrame'. Error in MotionBasedMultiObjectTracking (line 7) while hasFrame(obj.reader)
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Unrecognized function or variable 'hasFrame'.
Error in MotionBasedMultiObjectTracking (line 7)
while hasFrame(obj.reader)
how can we solve this problem
function MotionBasedMultiObjectTracking()
obj = setupSystemObjects()
tracks = initializeTracks();
nextId = 1;
while hasFrame(obj.reader)
frame = readFrame(obj.reader);
[centroids, bboxes, mask] = detectObjects(frame);
predictNewLocationsOfTracks();
[assignments, unassignedTracks, unassignedDetections] = ...
detectionToTrackAssignment();
updateAssignedTracks();
updateUnassignedTracks();
deleteLostTracks();
createNewTracks();
displayTrackingResults();
end
function obj = setupSystemObjects()
obj.reader= videoinput('winvideo',1);
obj.maskPlayer = vision.VideoPlayer('Position', [740, 400, 700, 400]);
obj.videoPlayer = vision.VideoPlayer('Position', [20, 400, 700, 400]);
obj.detector = vision.ForegroundDetector('NumGaussians', 3, ...
'NumTrainingFrames', 40, 'MinimumBackgroundRatio', 0.7);
obj.blobAnalyser = vision.BlobAnalysis('BoundingBoxOutputPort', true, ...
'AreaOutputPort', true, 'CentroidOutputPort', true, ...
'MinimumBlobArea', 400);
end
function tracks = initializeTracks()
tracks = struct(...
'id', {}, ...
'bbox', {}, ...
'kalmanFilter', {}, ...
'age', {}, ...
'totalVisibleCount', {}, ...
'consecutiveInvisibleCount', {});
end
function [centroids, bboxes, mask] = detectObjects(frame)
mask = obj.detector.step(frame);
mask = imopen(mask, strel('rectangle', [3,3]));
mask = imclose(mask, strel('rectangle', [15, 15]));
mask = imfill(mask, 'holes');
[~, centroids, bboxes] = obj.blobAnalyser.step(mask);
end
function predictNewLocationsOfTracks()
for i = 1:length(tracks)
bbox = tracks(i).bbox;
predictedCentroid = predict(tracks(i).kalmanFilter);
predictedCentroid = int32(predictedCentroid) - bbox(3:4) / 2;
tracks(i).bbox = [predictedCentroid, bbox(3:4)];
end
end
function [assignments, unassignedTracks, unassignedDetections] = ...
detectionToTrackAssignment()
nTracks = length(tracks);
nDetections = size(centroids, 1);
cost = zeros(nTracks, nDetections);
for i = 1:nTracks
cost(i, :) = distance(tracks(i).kalmanFilter, centroids);
end
costOfNonAssignment = 20;
[assignments, unassignedTracks, unassignedDetections] = ...
assignDetectionsToTracks(cost, costOfNonAssignment);
end
function updateAssignedTracks()
numAssignedTracks = size(assignments, 1);
for i = 1:numAssignedTracks
trackIdx = assignments(i, 1);
detectionIdx = assignments(i, 2);
centroid = centroids(detectionIdx, :);
bbox = bboxes(detectionIdx, :);
correct(tracks(trackIdx).kalmanFilter, centroid);
tracks(trackIdx).bbox = bbox;
tracks(trackIdx).age = tracks(trackIdx).age + 1;
tracks(trackIdx).totalVisibleCount = ...
tracks(trackIdx).totalVisibleCount + 1;
tracks(trackIdx).consecutiveInvisibleCount = 0;
end
end
function updateUnassignedTracks()
for i = 1:length(unassignedTracks)
ind = unassignedTracks(i);
tracks(ind).age = tracks(ind).age + 1;
tracks(ind).consecutiveInvisibleCount = ...
tracks(ind).consecutiveInvisibleCount + 1;
end
end
function deleteLostTracks()
if isempty(tracks)
return;
end
invisibleForTooLong = 20;
ageThreshold = 8;
ages = [tracks(:).age];
totalVisibleCounts = [tracks(:).totalVisibleCount];
visibility = totalVisibleCounts ./ ages;
lostInds = (ages < ageThreshold & visibility < 0.6) | ...
[tracks(:).consecutiveInvisibleCount] >= invisibleForTooLong;
tracks = tracks(~lostInds);
end
function createNewTracks()
centroids = centroids(unassignedDetections, :);
bboxes = bboxes(unassignedDetections, :);
for i = 1:size(centroids, 1)
centroid = centroids(i,:);
bbox = bboxes(i, :);
kalmanFilter = configureKalmanFilter('ConstantVelocity', ...
centroid, [200, 50], [100, 25], 100);
newTrack = struct(...
'id', nextId, ...
'bbox', bbox, ...
'kalmanFilter', kalmanFilter, ...
'age', 1, ...
'totalVisibleCount', 1, ...
'consecutiveInvisibleCount', 0);
tracks(end + 1) = newTrack;
nextId = nextId + 1;
end
end
function displayTrackingResults()
frame = im2uint8(frame);
mask = uint8(repmat(mask, [1, 1, 3])) .* 255;
minVisibleCount = 8;
if ~isempty(tracks)
reliableTrackInds = ...
[tracks(:).totalVisibleCount] > minVisibleCount;
reliableTracks = tracks(reliableTrackInds);
if ~isempty(reliableTracks)
bboxes = cat(1, reliableTracks.bbox);
ids = int32([reliableTracks(:).id]);
labels = cellstr(int2str(ids'));
predictedTrackInds = ...
[reliableTracks(:).consecutiveInvisibleCount] > 0;
isPredicted = cell(size(labels));
isPredicted(predictedTrackInds) = {' predicted'};
labels = strcat(labels, isPredicted);
frame = insertObjectAnnotation(frame, 'rectangle', ...
bboxes, labels);
mask = insertObjectAnnotation(mask, 'rectangle', ...
bboxes, labels);
end
end
obj.maskPlayer.step(mask);
obj.videoPlayer.step(frame);
end
end
1 Comment
Walter Roberson
on 10 Oct 2022
Which MATLAB version are you using? I suspect that you are using an old version
Answers (0)
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