Android APIs
public class

FaceDetector

extends Object
java.lang.Object
   ↳ android.media.FaceDetector

Class Overview

Identifies the faces of people in a Bitmap graphic object.

Summary

Nested Classes
class FaceDetector.Face A Face contains all the information identifying the location of a face in a bitmap. 
Public Constructors
FaceDetector(int width, int height, int maxFaces)
Creates a FaceDetector, configured with the size of the images to be analysed and the maximum number of faces that can be detected.
Public Methods
int findFaces(Bitmap bitmap, Face[] faces)
Finds all the faces found in a given Bitmap.
Protected Methods
void finalize()
Invoked when the garbage collector has detected that this instance is no longer reachable.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public FaceDetector (int width, int height, int maxFaces)

Added in API level 1

Creates a FaceDetector, configured with the size of the images to be analysed and the maximum number of faces that can be detected. These parameters cannot be changed once the object is constructed. Note that the width of the image must be even.

Parameters
width the width of the image
height the height of the image
maxFaces the maximum number of faces to identify

Public Methods

public int findFaces (Bitmap bitmap, Face[] faces)

Added in API level 1

Finds all the faces found in a given Bitmap. The supplied array is populated with FaceDetector.Faces for each face found. The bitmap must be in 565 format (for now).

Parameters
bitmap the Bitmap graphic to be analyzed
faces an array in which to place all found FaceDetector.Faces. The array must be sized equal to the maxFaces value set at initialization
Returns
int the number of faces found
Throws
IllegalArgumentException if the Bitmap dimensions don't match the dimensions defined at initialization or the given array is not sized equal to the maxFaces value defined at initialization

Protected Methods

protected void finalize ()

Added in API level 1

Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

Throws
Throwable