Ask Your Question
0

Query in face detection apps

asked 2013-07-01 23:18:44 -0500

Hardik gravatar image

In face detection apps, why only face is detected? why hands or background is not detected? what is the logic that only face is detected?

edit retag flag offensive close merge delete

Comments

please clarify, if you're talking about detection ( are there faces, where, and how many ) or recognition ( who is it )

a cascade based detection will return several faces, while the recognition will return the closest match from the training set.

berak gravatar imageberak ( 2013-07-02 04:27:24 -0500 )edit

Hardik, haar-like features are commonly used for face (or object) detection, but they can be used for face (object) recognition also. Check this paper: (The proposed system in this paper introduces the novel idea of using Haar-like features, which have commonly been used for object detection, along with a probabilistic classifier for face recognition.)

Nasrollahi, K., & Moeslund, T. B. HAAR-LIKE FEATURES FOR ROBUST REAL-TIME FACE RECOGNITION.

So, face detection and recognition are two different things

albertofernandez gravatar imagealbertofernandez ( 2013-07-02 08:01:10 -0500 )edit

albertofernandez, did you find a free version of above paper ?

berak gravatar imageberak ( 2013-07-02 13:36:25 -0500 )edit
1

thanks a ton ;)

berak gravatar imageberak ( 2013-07-03 02:46:45 -0500 )edit

1 answer

Sort by » oldest newest most voted
1

answered 2013-07-02 01:36:14 -0500

A detector is built in order to recognize faces. To train the detector, a set of face and non-face training images are used. For example:

The face training set consisted of 4916 hand labeled faces scaled and aligned to a base resolution of 24 by 24 pixels. The non-face subwindows used to train the detector come from 9544 images which were manually inspected and found to not contain any faces [1].

So this detector is designed to only detect faces. But you can train the detector to detect eyes, mouth,....

[1] Viola, P., & Jones, M. (2001). Rapid object detection using a boosted cascade of simple features. In Computer Vision and Pattern Recognition, 2001. CVPR 2001. Proceedings of the 2001 IEEE Computer Society Conference on (Vol. 1, pp. I-511). IEEE.

edit flag offensive delete link more

Comments

Thank you very much.

Hardik gravatar imageHardik ( 2013-07-02 02:10:24 -0500 )edit
Login/Signup to Answer

Question Tools

Stats

Asked: 2013-07-01 23:18:44 -0500

Seen: 62 times

Last updated: Jul 02 '13