android - 如何从 Android 中的自定义 CameraView 捕获图像？

Question

我需要从屏幕的所需部分捕获图像。

从相机

捕捉图像。

当时其他屏幕内容。

这怎么可能？

Answer 1

尝试使用 Surface View 来创建动态 相机 View 并在您需要的部分进行设置。

下面的代码试试

变量集类级别(全局)

Button btn_capture;
Camera camera1;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
public static boolean previewing = false;

onCreate() 方法中的代码

getWindow().setFormat(PixelFormat.UNKNOWN);
    surfaceView = new SurfaceView(this);
    surfaceHolder = surfaceView.getHolder();
    surfaceHolder.addCallback(this);
    surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
btn_capture = (Button) findViewById(R.id.button1);

surfaceView.setBackgroundResource(R.drawable.your_background_image);

if(!previewing){

        camera1 = Camera.open();
        if (camera1 != null){
            try {
                camera1.setDisplayOrientation(90);
                camera1.setPreviewDisplay(surfaceHolder);
                camera1.startPreview();
                previewing = true;
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

btn_capture.setOnClickListener(new OnClickListener() {

        public void onClick(View v) {
            // TODO Auto-generated method stub

            if(camera != null)
            {
                camera1.takePicture(myShutterCallback, myPictureCallback_RAW, myPictureCallback_JPG);

            }
        }
    });

以下代码将onCreate() 之后 放入您的类。

ShutterCallback myShutterCallback = new ShutterCallback(){

    public void onShutter() {
        // TODO Auto-generated method stub
    }};

PictureCallback myPictureCallback_RAW = new PictureCallback(){

    public void onPictureTaken(byte[] arg0, Camera arg1) {
        // TODO Auto-generated method stub
    }};

PictureCallback myPictureCallback_JPG = new PictureCallback(){

    public void onPictureTaken(byte[] arg0, Camera arg1) {
        // TODO Auto-generated method stub
        Bitmap bitmapPicture = BitmapFactory.decodeByteArray(arg0, 0, arg0.length);

        Bitmap correctBmp = Bitmap.createBitmap(bitmapPicture, 0, 0, bitmapPicture.getWidth(), bitmapPicture.getHeight(), null, true);

    }};

public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {
    // TODO Auto-generated method stub
    if(previewing){
        camera1.stopPreview();
        previewing = false;
    }

    if (camera1 != null){
        try {
            camera1.setPreviewDisplay(surfaceHolder);
            camera1.startPreview();
            previewing = true;
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

public void surfaceCreated(SurfaceHolder holder) {
    // TODO Auto-generated method stub

}

public void surfaceDestroyed(SurfaceHolder holder) {
    // TODO Auto-generated method stub

        camera1.stopPreview();
        camera1.release();
        camera1 = null;
        previewing = false;

}

在 AndroidManifest.xml 中赋予用户权限。

<uses-permission android:name="android.permission.CAMERA"/>
<uses-feature android:name="android.hardware.camera" android:required="false"/>
<uses-feature android:name="android.hardware.camera.front" android:required="false"/>

也不要忘记( implements SurfaceHolder.Callback ) 上课。