android – Make a SurfaceView larger than the screen (Fitting a camera preview to a SurfaceView larger than the display)-ThrowExceptions

Exception or error:

I have a custom camera application and I want for any preview sizes to display it in full screen mode without stretching the camera preview image.
For this, I need to make the surfaceView larger than the screen in order to keep aspect ratio, so actually the user will see less than camera actually captures.

For some reason, I cannot make the SurfaceView larger than the screen size.

What I’ve tried so far:

  • resize camera preview in surfaceChanged method

  • resize camera preview in on onMeasure method

  • resize it in in onLayout method
  • adding FLAG_LAYOUT_NO_LIMITS to activity – info
  • adding android:clipChildren for the surface view – info
  • setting width in xml: android:layout_width="852px"
  • getWindow().setLayout(852, 1280); in activity

but without any success – the behaviour is the same each time: it appears ok for 1 second and after that it gets stretched.

Here is the code:

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

    private static final int CAMERA_ROTATE_ANGLE = 90;

    private SurfaceHolder cameraHolder;
    private Camera androidHardCamera;
    private Context context;

    public CameraPreview(Context context) {
        super(context);
        this.context = context;

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        cameraHolder = getHolder();
        cameraHolder.addCallback(this);
        // deprecated setting, but required on Android versions prior to 3.0
        cameraHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void setCamera(Camera camera) {
        this.androidHardCamera = camera;
        if (androidHardCamera != null) {
            requestLayout();
        }
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        // The Surface has been created, now tell the camera where to draw the preview.
        try {
            if (androidHardCamera != null) {
                androidHardCamera.stopPreview();//this is needed for devices with API level < 14 (from doc.: Starting
                // from API level 14, this method, aka setDisplayOrientation, can be called when preview is active.)

                androidHardCamera.setDisplayOrientation(CAMERA_ROTATE_ANGLE);//force the preview Display Orientation
                // to Portrait (rotate camera orientation/display to portrait)

                //holder.setFixedSize(852, 1280);
                androidHardCamera.setPreviewDisplay(holder);
                androidHardCamera.startPreview();
            }
        } catch (IOException e) {
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        // If your preview can change or rotate, take care of those events here.
        // Make sure to stop the preview before resizing or reformatting it.

        if (cameraHolder.getSurface() == null) {
            // preview surface does not exist
            return;
        }

        // stop preview before making changes
        try {
            androidHardCamera.stopPreview();
        } catch (Exception e) {
            // ignore: tried to stop a non-existent preview
        }

        // set preview size and make any resize, rotate or
        // reformatting changes here
        FrameLayout.LayoutParams layoutParams = (FrameLayout.LayoutParams) this.getLayoutParams();
        layoutParams.height = 1280;
        layoutParams.width = 852;
        this.setLayoutParams(layoutParams);

        //cameraHolder.setFixedSize(852, 1280);
        requestLayout();

        // start preview with new settings
        try {
            androidHardCamera.setPreviewDisplay(cameraHolder);
            androidHardCamera.startPreview();
        } catch (Exception e) {
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
    }

//    @Override
//    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
//       // super.onMeasure(widthMeasureSpec, heightMeasureSpec);    //To change body of overridden methods use File | Settings | File Templates.
//        //super.onMeasure(852, 1280);
//        setMeasuredDimension(852, 1280);
//    }
}

public class MyActivity extends Activity{

    private Camera camera;
    private CameraPreview previewCamera;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

        setContentView(R.layout.camera_screen);

        previewCamera = new CameraPreview(this);
        FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
        preview.addView(previewCamera);

        //getWindow().setLayout(852, 1280);
    }

    @Override
    protected void onResume() {
        // Create an instance of Camera
        camera = getCameraInstance(1);
        if (camera == null) {
            Toast.makeText(this, "Camera in use!", Toast.LENGTH_LONG).show();
        } else {
            previewCamera.setCamera(camera);
            camera.stopPreview();

            Camera.Parameters p = camera.getParameters();
            p.setPreviewSize(176, 144);
            // p.setPreviewSize(480, 800);
            camera.setParameters(p);

            startPreviewCamera();
        }
        super.onResume();
    }

    @Override
    protected void onPause() {
        releaseCameraAndPreview();
        super.onPause();
    }

    public Camera getCameraInstance(int cameraInstance) {
        Camera c = null;
        try {
            c = Camera.open(cameraInstance);
        } catch (Exception e) {
            // Camera is not available (in use or does not exist)
            System.out.println("exception: " + e);
        }
        return c;
    }

    public void startPreviewCamera() {
        //Force the preview Display Orientation to Portrait (rotate camera orientation/display to portrait)
        camera.setDisplayOrientation(90);
        camera.startPreview();
    }

    public void releaseCameraAndPreview() {
        if (camera != null) {
            camera.stopPreview(); // updating the preview surface
            camera.setPreviewCallback(null);
            // camera.lock(); //if we don't lock the camera, release() will fail on some devices
            camera.release();
            camera = null;
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <!-- This is the container for the camera preview screen -->
    <FrameLayout android:id="@+id/camera_preview"
                 android:layout_width="match_parent"
                 android:layout_height="match_parent"
                 android:clipChildren="false"
                 android:layout_weight="1"/>
</LinearLayout>

Here is the entire project: https://www.dropbox.com/sh/96jih9kw5zmmnzy/z7VX16T30M

I am testing on a S3 device. On a S2 device seems to wok fine… I just do not know what to do more to solve this issue…

UPDATE 1

For example Sony Xperia has a screen display of 480 / 854.
One of the preview sizes I can use is 176 / 144.

In order to display full screen size I need to have the preview camera size of 698 / 854 – but I do not know how to set this value and where.

The code below is not working… the camera preview is stretched/elongated.

import android.app.Activity;
import android.graphics.Point;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.Display;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.LinearLayout;

public class CameraPreview extends Activity implements Preview.PreviewListener {

    private Preview mPreview;
    private Camera mCamera;

    FrameLayout preview;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.main);

        // Create our Preview view and set it as the content of our activity.
        mPreview = new Preview(this);
        preview = (FrameLayout) findViewById(R.id.surface_camera);
        preview.addView(mPreview);

        Display display = getWindowManager().getDefaultDisplay();
        getDisplaySize(display);
    }

    private static Point getDisplaySize(final Display display) {
        final Point point = new Point();
        try {
            display.getSize(point);
        } catch (java.lang.NoSuchMethodError ignore) {
            point.x = display.getWidth();
            point.y = display.getHeight();
        }
        System.out.println("============: Screen " + point.x + "/" + point.y);
        return point;
    }

    @Override
    protected void onResume() {
        super.onResume();
        mCamera = Camera.open(1);
        mPreview.setCamera(mCamera, this);
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (mCamera != null) {
            mPreview.setCamera(null, null);
            mCamera.release();
            mCamera = null;
        }
    }


    @Override
    public void onSurfaceChanged() {
        LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) preview.getLayoutParams();
        params.setMargins(0, -218, 0, 0);
        preview.setLayoutParams(new FrameLayout.LayoutParams(480, 854));
        preview.setLayoutParams(params);

        preview.setVisibility(View.VISIBLE);
    }
}

import android.content.Context;
import android.hardware.Camera;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

import java.io.IOException;
import java.util.List;

class Preview extends SurfaceView implements SurfaceHolder.Callback {

    private SurfaceHolder mHolder;
    private Camera mCamera;

    private PreviewListener listener;

    public static interface PreviewListener {
        void onSurfaceChanged();
    }

    Preview(Context context) {
        super(context);

        mHolder = getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void setCamera(Camera camera, PreviewListener listener) {
        this.listener = listener;
        mCamera = camera;
        if (mCamera != null) {
            List<Camera.Size> mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
            for (Camera.Size s : mSupportedPreviewSizes) {
                System.out.println("============: " + s.width + "/" + s.height);
            }
            requestLayout();
        }
    }

    public void surfaceCreated(SurfaceHolder holder) {
        // The Surface has been created, acquire the camera and tell it where
        // to draw.
        try {
            if (mCamera != null) {
                mCamera.setPreviewDisplay(holder);
            }
        } catch (IOException exception) {
            Log.e("Error: ", "IOException caused by setPreviewDisplay()", exception);
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // Surface will be destroyed when we return, so stop the preview.
        if (mCamera != null) {
            mCamera.stopPreview();
        }
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        mCamera.stopPreview(); // pe Xpedia daca nu pui asta crapa la  setDisplayOrientation

        // Now that the size is known, set up the camera parameters and beginthe preview.
        Camera.Parameters parameters = mCamera.getParameters();

        mCamera.setDisplayOrientation(90);
        parameters.setPreviewSize(176, 144);

        requestLayout();

        mCamera.setParameters(parameters);
        mCamera.startPreview();
    }

//    @Override
//    protected void onSizeChanged(\int w, int h, int oldw, int oldh) {
//        super.onSizeChanged(w, h, oldw, oldh);
//        //setLayoutParams(new LayoutParams((int)RATIO * w, w));
//
//        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) getLayoutParams();
//        setLayoutParams(new FrameLayout.LayoutParams(960, 1280));
//        params.setMargins(0, -120, 0,0);
//        setLayoutParams(params);
//
//        //preview.setVisibility(View.VISIBLE);
//    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);    //To change body of overridden methods use File | Settings | File Templates.

//        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) getLayoutParams();
//       setLayoutParams(new FrameLayout.LayoutParams(698, 854));
//        params.setMargins(0, -218, 0,0);
//        setLayoutParams(params);
    }

    //https://stackoverflow.com/questions/11853297/change-size-of-android-custom-surfaceview
    @Override
    public void onLayout(boolean changed, int left, int top, int right, int bottom) {
        if (changed) {
            //setLayoutParams();
                 listener.onSurfaceChanged();
            //(this).layout(0, 0, viewWidth , viewHeight);
        }
    }

}

This is a class test which calculates the correct surface view size based on display screen size and camera preview size:

public class Test {

    /**
     * Determine proper width to be used for surface view in order to not stretch the camera live preview.
     */
    public static void main(String[] args) {
        // camera preview size:
        int surfaceViewWidth = 176;
        int surfaceViewHeight = 144;

        int holder;
        if (surfaceViewWidth > surfaceViewHeight) {
            holder = surfaceViewWidth;
            surfaceViewWidth = surfaceViewHeight;
            surfaceViewHeight = holder;
        }

        //device screen display sizes:
        int width = 480;
        int height = 854;

        double sc1 = (double) width / surfaceViewWidth;
        double sc2 = (double) height / surfaceViewHeight;
        double rez;
        if (sc1 > sc2) {
            rez = sc1;
        } else {
            rez = sc2;
        }

        System.out.println("Width/height: " + (int) (surfaceViewWidth * rez) + "/" + (int) (surfaceViewHeight * rez)); // size of the preview size we need to set
        System.out.println(((int) (surfaceViewWidth * rez))-width); // difference between preview size and device screen size = whit how much is bigger the preview size than screen size 
    }
}
How to solve:

First, remove source of crashes: startPreviewCamera called in onResume.
Camera preview shall be started in SurfaceHolder.Callback methods.

Then you should know that you can set preview size only to sizes reported by Camera.Parameters.getSupportedPreviewSizes. And these sizes will most likely be smaller or equal to device’s screen size.

Then you simply call

Camera.Parameters p = camera.getParameters();
p.setPreviewSize(w, h); // one of supported sizes
camera.setParameters(p);

Then Surface of preview will have that size (possibly rotated and w/h swapped). And this surface will be rescaled by Android to size of your CameraPreview view when being drawn, so it’s also important how you set size of your CameraPreview.

You can set fixed size of your CameraPreview simply by calling

previewCamera.setLayoutParams(new FrameLayout.LayoutParams(w, h));

So in short, you set requested preview size in Camera.setParameters, and you size your preview view as desired, possibly to same size as preview, as is your requirement. Your preview view then may be equal to screen size or be smaller (assuming camera doesn’t provide preview bigger than screen). If camera provides bigger preview than screen, you can still call preview.setX, preview.setY to move it around.

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