/*
* Copyright (C) 2012 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cn.hugo.android.scanner.camera;
import android.hardware.Camera;
import android.util.Log;
/**
* 该类用于检测手机上摄像头的个数，如果有两个摄像头，则取背面的摄像头
*/
public final class OpenCameraInterface {
private static final String TAG = OpenCameraInterface.class.getName();
private OpenCameraInterface() {
}
/**
* Opens a rear-facing camera with {@link Camera#open(int)}, if one exists,
* or opens camera 0.
*/
public static Camera open() {
int numCameras = Camera.getNumberOfCameras();
if (numCameras == 0) {
Log.w(TAG, "No cameras!");
return null;
}
int index = 0;
while (index < numCameras) {
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
Camera.getCameraInfo(index, cameraInfo);
// CAMERA_FACING_BACK：手机背面的摄像头
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {
break;
}
index++;
}
Camera camera;
if (index < numCameras) {
Log.i(TAG, "Opening camera #" + index);
camera = Camera.open(index);
} else {
Log.i(TAG, "No camera facing back; returning camera #0");
camera = Camera.open(0);
}
return camera;
}
}
