%%?detectAndTrackFaces
%?Automatically?detects?and?tracks?multiple?faces?in?a?webcam-acquired
%?video?stream.
%
%?Copyright?2013-2014?The?MathWorks?Inc?

clear?classes;

%%?Instantiate?video?device?face?detector?and?KLT?object?tracker
vidObj?=?webcam;

faceDetector?=?vision.CascadeobjectDetector（）;?%?Finds?faces?by?default
tracker?=?MultiobjectTrackerKLT;

%%?Get?a?frame?for?frame-size?information
frame?=?snapshot（vidObj）;
frameSize?=?size（frame）;

%%?Create?a?video?player?instance
videoPlayer??=?vision.VideoPlayer（‘Position‘[200?100?fliplr（frameSize（1:2）+30）]）;

%%?Iterate?until?we?have?successfully?detected?a?face
bboxes?=?[];
while?isempty（bboxes）
????framergb?=?snapshot（vidObj）;
????frame?=?rgb2gray（framergb）;
????bboxes?=?faceDetector.step（frame）;
end
tracker.addDetections（frame?bboxes）;

%%?And?loop?until?the?player?is?closed
frameNumber?=?0;
keepRunning?=?true;
disp（‘Press?Ctrl-C?to?exit...‘）;
while?keepRunning
????
????framergb?=?snapshot（vidObj）;
????frame?=?rgb2gray（framergb）;
????
????if?mod（frameNumber?10）?==?0
????????%?（Re）detect?faces.
????????%
????????%?NOTE:?face?detection?is?more?expensive?than?imresize;?we?can
????????%?speed?up?the?implementation?by?reacquiring?faces?using?a
????????%?downsampled?frame:
????????%?bboxes?=?faceDetector.step（frame）;
????????bboxes?=?2?*?faceDetector.step（imresize（frame?0.5））;
????????if?~isempty（bboxes）
????????????tracker.addDetections（frame?bboxes）;
????????end
????else
????????%?Track?faces
????????tracker.track（frame）;
????end
????
????%?Display?bounding?boxes?and?tracked?points.
????displayframe?=?insertobjectAnnotation（framergb?‘rectangle‘...
????????tracker.Bboxes?tracker.BoxIds）;
????displayframe?=?insertMarker（displayframe?tracker.Points）;
????videoPlayer.step（displayframe）;
????
????frameNumber?=?frameNumber?+?1;
end

%%?Clean?up
release（videoPlayer）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????1921??2016-09-01?11:27??detectAndTrackFaces.m
?????文件????????7988??2016-09-01?11:27??MultiobjectTrackerKLT.m
?????文件????????1526??2016-09-01?11:27??license.txt