Face detection in android media apps
Adding more value to applicationsHackathon, Mobile DayEndava24.06.2013
• Face detection/recognition – what’s all about?
• Pioneers in face recognition
• Add value to your media apps
• What we want to…
• Tools & technologies
• How it’s all mixed up?
• How all things work together?
• How can we make it work?
• Some facts
• Don’t forget about privacy
• Q&A
Highlights
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Face detection/recognition – what’s all about?
•Face detection
• Definition
• Use cases
•Face recognition
•Definition
•Use cases
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Pioneers in face recognition
•Marker points (position of eyes, ears, nose)
• Kanade, T. (November 1973) - Euclidean distance between feature vectors of a probe and reference image
• Eigenfaces – Turk, M. & Pentland, A. – a holistic approach to face recognition
• Fisherfaces – Belhumeur, P. N., Hespanha, J., and Kriegman, D. (1997) - Eigenfaces vs. Fisherfaces
• Local feature extraction:
• Gabor Wavelets – Wiskott, L., Fellous, J., Krüger, N., Malsburg, C. (1997)
• Discrete Cosinus Transform – Messer, K. (2006
• Local Binary Patterns – Ahonen, T., Hadid, A., and Pietikainen, M. (2004)
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Add value to your media apps
• Face tagging in social media
• Sharing – open new ways to share
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Add value to your media apps
•Android Device lock, specific applications face authorization
•Determining friends in video clips
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What we want to…
•Detect faces in a specific image
• Recognize a tagged contact in Android Media library
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Tools & technologies
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How it’s all mixed up?
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How all things work together?
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How can we make it work?
Mat imgGray = imread(originalImageName, CV_LOAD_IMAGE_GRAYSCALE);CascadeClassifier face_cascade;if(face_cascade.load(cascadeFilePath)){ face_cascade.detectMultiScale(loadedImageData, faces);}
Ptr<FaceRecognizer> recognizer = createLBPHFaceRecognizer();//training modelrecognizer->train(images, labels);
//face predictionrecognizer->predict(scalledFace, predicted_label, predicted_confidence);
Face detection
Face detection
Face recognition
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Some facts about face recognition
14 faces 25 faces 40 faces0.00
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Recognition ratio
Local Binary Paths Histogram (LBPH) FisherFaces EigenFaces
Perc
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Don’t forget about privacy
•Make use of privacy policies and/or disclaimers
Privacy matters to me!!!That’s why I’m using privacy visor…
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Q&A
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That’s it…
Vasile Chelban | Android Developer
thank you
http://opencv.org/platforms/android.html
http://developer.android.com/tools/sdk/ndk/index.html
http://developer.android.com/sdk/index.html