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Android中调用摄像头预览的步骤如下：

1.SurfaceView相关

    //定义对象
    private SurfaceView photoView;     // SurfaceView对象：(视图组件)视频显示
    private SurfaceHolder photoHolder; // SurfaceHolder对象：(抽象接口)SurfaceView支持类 
    private Camera camera;         // Camera对象，相机预览

//SurfaceView对象的设置
        photoHolder=photoView.getHolder(); // 绑定SurfaceView，取得SurfaceHolder对象
        photoHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);  //设置显示器类型
        photoHolder.setFixedSize(100, 100);
        photoHolder.addCallback(callback); // SurfaceHolder加入回调接口

2. 实现SurfaceHolder.Callback接口的实现

    SurfaceHolder.Callback callback=new SurfaceHolder.Callback() {
        
        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {
            // TODO Auto-generated method stub
            camera.setPreviewCallback(null);
            camera.stopPreview();
            camera.release();
            camera=null;
        }
        
        @Override
        public void surfaceCreated(SurfaceHolder holder) {
            // TODO Auto-generated method stub
            camera=Camera.open();
            try {
                camera.setPreviewDisplay(photoHolder);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height) {
            // TODO Auto-generated method stub
            initCamera();
        }
    };

3.Camera属性的设置

    //摄像头属性的设置
    public void initCamera(){
        Camera.Parameters parameters=camera.getParameters();   //得到摄像头属性
        camera.setDisplayOrientation(90);   //旋转90度（不设置时，会横向显示）
        camera.setParameters(parameters);  //将属性值保存至Camera的参数中    }