How to verify if the face has been detected ?

My code is:

while hasFrame(videoFileReader)
    videoFrame = readFrame(videoFileReader);
    
    bbox = faceDetector(videoFrame); %detect the face
    videoFrame = insertShape(videoFrame, 'Rectangle', bbox); % place a box around the face
    
    %% i want to add an IF statment to verify first if bbox is true !
    
    %crop the rounded face and save it
    FacCrop=imcrop(videoFrame,bbox);
    fname = sprintf('FaceCropped_%d.jpg',i);
    fpath = fullfile('E:', fname);
    imwrite(FacCrop, fpath); 
    i=i+1;
    
end

• but since there's some frames where the face can't be detected, that means no bbox, so it returns an error in the imcrop function and won't finnish the rest of the video !

Error using images.internal.imageDisplayParsePVPairs (line 125)
Invalid input arguments.

Error in images.internal.imageDisplayParseInputs (line 69)
[common_args,specific_args] = images.internal.imageDisplayParsePVPairs(varargin{:});

Error in imshow (line 245)
    images.internal.imageDisplayParseInputs({'Parent','Border','Reduce'},preparsed_varargin{:});
    
Error in imcrop>parseInputs (line 252)
            imshow(a,cm);

Error in imcrop (line 93)
[x,y,a,cm,spatial_rect,h_image,placement_cancelled] = parseInputs(varargin{:});

Error in FaceTracking (line 19)
    FacCrop=imcrop(videoFrame,bbox);
 

So what i want, is first to verify if the face has been detected or not in bbox, to call the crop function, else, skipp the crop step.

I hope you get my problem, and I hope I find a solution from you guys.

Thanks in advance.

[ABDELKARIM MELIKI]

Also Iam a beginner so take it easy on me ?

Answer 1

[Filipe Fernandes]

Hello, you could try use

while hasFrame(videoFileReader) videoFrame = readFrame(videoFileReader);

    bbox = faceDetector(videoFrame); %detect the face
    if ~isempty(bbox)
        videoFrame = insertShape(videoFrame, 'Rectangle', bbox); % place a box around the face

        %crop the rounded face and save it
        FacCrop=imcrop(videoFrame,bbox);
       fname = sprintf('FaceCropped_%d.jpg',i);
       fpath = fullfile('E:', fname);
       imwrite(FacCrop, fpath); 
    end
    i=i+1; 
end

[ABDELKARIM MELIKI]

thank you Filipe, I did the same code ...