Android Camera实现毫秒级拍照实例

我们知道自定义Camera需要以下几步

1. 打开相机，即实例化Camera对象，Camera camera = Camera.open();
2. 设置Camera的相关参数，Camera.Parameters parameters = camera.getParameters();
3. 打开预览，camera.setPreviewDisplay(surfaceholder); camera.startPreview();
4. 获取图片，这里只是从预览中获取因此使用，camera.setPreviewCallback(new Camera.PreviewCallback(){……..});
5. 停止预览，释放相机，camera.stopPreview();camera.release();

1、打开相机

public static Camera openFacingBackCamera() {    Camera cam = null;    Camera.Camerainfo cameraInfo = new Camera.CameraInfo();    for (int camIdx = 0, cameraCount = Camera.getNumberOfCameras(); camIdx < cameraCount; camIdx++) {      Camera.getCameraInfo(camIdx, cameraInfo);      if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {        try {          //打开相应的摄像头，目前是前置摄像头          cam = Camera.open(camIdx);        } catch (RuntimeException e) {          e.printStackTrace();          if (cam!=null){            cam.stopPreview();            cam.release();          }          cam = null;        }      }    }    return cam;  }