Camera Tutorial for Android (using surfaceview)-ThrowExceptions

Exception or error:

Here is my example code:

package newslab.video.server;

import android.app.Activity;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class VideoServer extends Activity implements SurfaceHolder.Callback {
    TextView testView;

    Camera camera;
    SurfaceView surfaceView;
    SurfaceHolder surfaceHolder;

    private final String tag = "VideoServer";

    Button start, stop;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        start = (Button)findViewById(R.id.btn_start);
        start.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View arg0) {
                start_camera();
            }
        });

        stop = (Button)findViewById(R.id.btn_stop);
        stop.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View arg0) {
                stop_camera();
            }
        });

        surfaceView = (SurfaceView)findViewById(R.id.surfaceView1);
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    private void start_camera() {
        try{
            camera = Camera.open();
        }catch(RuntimeException e){
            Log.e(tag, "init_camera: " + e);
            return;
        }
        Camera.Parameters param;
        param = camera.getParameters();
        //modify parameter
        param.setPreviewFrameRate(20);
        param.setPreviewSize(176, 144);
        camera.setParameters(param);
        try {
            camera.setPreviewDisplay(surfaceHolder);
            camera.startPreview();
        } catch (Exception e) {
            Log.e(tag, "init_camera: " + e);
            return;
        }
    }

    private void stop_camera() {
        camera.stopPreview();
        camera.release();
    }

    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        // TODO Auto-generated method stub
    }

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

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

However, it just shows the preview and stop the camera.
Is there any other tutorial to teach further processing such as how to save the image or process the image with bitmap?

How to solve:

Ok. So here is the solution:

I am not adding any try catch.
This is simply for the capturing the image and storing it into the sdcard.

public class VideoServer extends Activity implements SurfaceHolder.Callback {
    TextView testView;

    Camera camera;
    SurfaceView surfaceView;
    SurfaceHolder surfaceHolder;
    PictureCallback rawCallback;
    ShutterCallback shutterCallback;
    PictureCallback jpegCallback;
    private final String tag = "VideoServer";

    Button start, stop, capture;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        start = (Button)findViewById(R.id.btn_start);
        start.setOnClickListener(new Button.OnClickListener()
        {
            public void onClick(View arg0) {
                start_camera();
            }
        });
        stop = (Button)findViewById(R.id.btn_stop);
        capture = (Button) findViewById(R.id.capture);
        stop.setOnClickListener(new Button.OnClickListener()
        {
            public void onClick(View arg0) {
                stop_camera();
            }
        });
        capture.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                captureImage();
            }
        });

        surfaceView = (SurfaceView)findViewById(R.id.surfaceView1);
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        rawCallback = new PictureCallback() {
            public void onPictureTaken(byte[] data, Camera camera) {
                Log.d("Log", "onPictureTaken - raw");
            }
        };

        /** Handles data for jpeg picture */
        shutterCallback = new ShutterCallback() {
            public void onShutter() {
                Log.i("Log", "onShutter'd");
            }
        };
        jpegCallback = new PictureCallback() {
            public void onPictureTaken(byte[] data, Camera camera) {
                FileOutputStream outStream = null;
                try {
                    outStream = new FileOutputStream(String.format(
                            "/sdcard/%d.jpg", System.currentTimeMillis()));
                    outStream.write(data);
                    outStream.close();
                    Log.d("Log", "onPictureTaken - wrote bytes: " + data.length);
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                }
                Log.d("Log", "onPictureTaken - jpeg");
            }
        };
    }

    private void captureImage() {
        // TODO Auto-generated method stub
        camera.takePicture(shutterCallback, rawCallback, jpegCallback);
    }

    private void start_camera()
    {
        try{
            camera = Camera.open();
        }catch(RuntimeException e){
            Log.e(tag, "init_camera: " + e);
            return;
        }
        Camera.Parameters param;
        param = camera.getParameters();
        //modify parameter
        param.setPreviewFrameRate(20);
        param.setPreviewSize(176, 144);
        camera.setParameters(param);
        try {
            camera.setPreviewDisplay(surfaceHolder);
            camera.startPreview();
            //camera.takePicture(shutter, raw, jpeg)
        } catch (Exception e) {
            Log.e(tag, "init_camera: " + e);
            return;
        }
    }

    private void stop_camera()
    {
        camera.stopPreview();
        camera.release();
    }

    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        // TODO Auto-generated method stub
    }

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

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

}

Don’t press caputure button before the start,because I didn’t checked it. I just wanted to show you that how to capture and store image into the sdcard.

###

Dont forget to take the permission for using camera in Android Manifest file,

<uses-permission android:name="android.permission.CAMERA" ></uses-permission>

Also you have to take permission for storing images on SD Card,

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

###

Camera permission in manifiest file:

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

Permission for storing image from sdcard in manifiest file:

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

###

I was having issues with camera, figuring out how to implement and work with and came across this resources: Camera preview. At the bottom of the page you have examples of the most common scenarios as well as the one in your original question: Take and preview Photo

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