Android studio camera2消除噪音

时间：2016-08-31 22:33:34

标签： android image-processing

我在android studio中使用相机，我通过ImageReader从camera2输出YUV420_888。问题是我得到了这种奇怪的声音，或者不管它叫什么。这是图片link。如果你仔细观察，有6-7个圆圈有不同的灰色阴影。我只使用Y通道，因为我需要黑白图像，Y通道就是这样。这是一个大问题，因为它干扰边缘检测算法和那些“圆”在边缘检测中表示为噪声。此外，它们仅在表面为白色时出现。谁能告诉我为什么会发生这种情况以及如何解决它？

编辑： 所以我发现了它的代码。这是原始应用程序，我试图让camera2工作。

package com.example.nikola.camera2project; 

import android.hardware.camera2.CaptureResult;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.graphics.ImageFormat;
import android.graphics.SurfaceTexture;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.hardware.camera2.CameraMetadata;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.TotalCaptureResult;
import android.hardware.camera2.params.StreamConfigurationMap;
import android.media.Image;
import android.media.ImageReader;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.HandlerThread;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.Size;
import android.util.SparseIntArray;
import android.view.Surface;
import android.view.SurfaceView;
import android.view.TextureView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "AndroidCameraApi";
    private TextureView textureView;
    private static final SparseIntArray ORIENTATIONS = new SparseIntArray();
    static {
        ORIENTATIONS.append(Surface.ROTATION_0, 90);
        ORIENTATIONS.append(Surface.ROTATION_90, 0);
        ORIENTATIONS.append(Surface.ROTATION_180, 270);
        ORIENTATIONS.append(Surface.ROTATION_270, 180);
    }
    private String cameraId;
    protected CameraDevice cameraDevice;
    protected CameraCaptureSession cameraCaptureSessions;
    protected CaptureRequest.Builder captureRequestBuilder;
    private Size imageDimension;
    private ImageReader imageReader;
    private File file;
    private static final int REQUEST_CAMERA_PERMISSION = 200;

    private Handler mBackgroundHandler;
    private HandlerThread mBackgroundThread;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_main);
        textureView = (TextureView) findViewById(R.id.texture);
        assert textureView != null;
        textureView.setSurfaceTextureListener(textureListener);
        imageReader = ImageReader.newInstance(640, 480, ImageFormat.YUV_420_888, 1);




    }


    TextureView.SurfaceTextureListener textureListener = new TextureView.SurfaceTextureListener() {
        @Override
        public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
            //open your camera here
            openCamera();
        }
        @Override
        public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
            // Transform you image captured size according to the surface width and height
        }
        @Override
        public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
            return false;
        }
        @Override
        public void onSurfaceTextureUpdated(SurfaceTexture surface) {
        }
    };



    private final CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {
        @Override
        public void onOpened(CameraDevice camera) {
            //This is called when the camera is open
            Log.e(TAG, "onOpened");
            cameraDevice = camera;
            createCameraPreview();

        }
        @Override
        public void onDisconnected(CameraDevice camera) {
            cameraDevice.close();
        }
        @Override
        public void onError(CameraDevice camera, int error) {
            cameraDevice.close();
            cameraDevice = null;
        }
    };
    protected void startBackgroundThread() {
        mBackgroundThread = new HandlerThread("Camera Background");
        mBackgroundThread.start();
        mBackgroundHandler = new Handler(mBackgroundThread.getLooper());
    }
    protected void stopBackgroundThread() {
        mBackgroundThread.quitSafely();
        try {
            mBackgroundThread.join();
            mBackgroundThread = null;
            mBackgroundHandler = null;
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    protected void createCameraPreview() {
        try {
            SurfaceTexture texture = textureView.getSurfaceTexture();
            assert texture != null;
            texture.setDefaultBufferSize(imageDimension.getWidth(), imageDimension.getHeight());
            Surface surface = new Surface(texture);
            captureRequestBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
             captureRequestBuilder.addTarget(surface);
           cameraDevice.createCaptureSession(Arrays.asList(surface), new CameraCaptureSession.StateCallback(){
                @Override
                public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
                    //The camera is already closed
                    if (null == cameraDevice) {
                        return;
                    }
                    // When the session is ready, we start displaying the preview.
                    cameraCaptureSessions = cameraCaptureSession;
                    updatePreview();
                }
                @Override
                public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {
                    Toast.makeText(MainActivity.this, "Configuration change", Toast.LENGTH_SHORT).show();
                }
            }, null);


        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }
    private void openCamera() {
        CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
        Log.e(TAG, "is camera open");
        try {
            cameraId = manager.getCameraIdList()[0];
            CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);
            StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
            assert map != null;
            imageDimension = map.getOutputSizes(SurfaceTexture.class)[0];
            // Add permission for camera and let user grant the permission
            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CAMERA_PERMISSION);
                return;
            }
            manager.openCamera(cameraId, stateCallback, null);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
        Log.e(TAG, "openCamera X");
    }
    protected void updatePreview() {
        if(null == cameraDevice) {
            Log.e(TAG, "updatePreview error, return");
        }
        captureRequestBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
        try {
            cameraCaptureSessions.setRepeatingRequest(captureRequestBuilder.build(), null, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }
    private void closeCamera() {
        if (null != cameraDevice) {
            cameraDevice.close();
            cameraDevice = null;
        }
        if (null != imageReader) {
            imageReader.close();
            imageReader = null;
        }
    }
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        if (requestCode == REQUEST_CAMERA_PERMISSION) {
            if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
                // close the app
                Toast.makeText(MainActivity.this, "Sorry!!!, you can't use this app without granting permission", Toast.LENGTH_LONG).show();
                finish();
            }
        }
    }
    @Override
    protected void onResume() {
        super.onResume();
        Log.e(TAG, "onResume");
        startBackgroundThread();
        if (textureView.isAvailable()) {
            openCamera();
        } else {
            textureView.setSurfaceTextureListener(textureListener);
        }
    }
    @Override
    protected void onPause() {
        Log.e(TAG, "onPause");
        //closeCamera();
        stopBackgroundThread();
        super.onPause();
    }

}

因为我需要做一些围绕帧的工作，这是我做的改变

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_main);
surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
        assert surfaceView != null;
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        mImageReader = ImageReader.newInstance(480,640, ImageFormat.YUV_420_888,10);
}

private final CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {
        @Override
        public void onOpened(CameraDevice camera) {
            //This is called when the camera is open
            Log.e(TAG, "onOpened");
            cameraDevice = camera;
            createCameraPreview();
            mImageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() {
                @Override
                public void onImageAvailable(ImageReader reader) {
                    Image image =  reader.acquireLatestImage();
                    if(image != null) {
                        ByteBuffer buffer0 = image.getPlanes()[0].getBuffer();
                        byte[] Y = new byte[buffer0.remaining()];
                        buffer0.get(Y);

                        //I do work here but this is for preview grayscale only

                        byte[] Bits = new byte[Y.length * 4]; //That's where the RGBA array goes.

                        for (int i = 0; i < Y.length; i++) {
                            Bits[i * 4] =
                                    Bits[i * 4 + 1] =
                                            Bits[i * 4 + 2] = Y[i];
                            Bits[i * 4 + 3] = -1;//0xff, that's the alpha.
                        }

                        Bitmap bm = Bitmap.createBitmap(image.getWidth(), image.getHeight(), Bitmap.Config.ARGB_8888);
                        bm.copyPixelsFromBuffer(ByteBuffer.wrap(Bits));
                        Bitmap scaled = Bitmap.createScaledBitmap(bm, (int) (surfaceView.getHeight() * 1.33333), surfaceView.getHeight(), true);
                        Canvas c;
                        c = surfaceHolder.lockCanvas();
                        c.drawBitmap(scaled, 0, 0, null);
                        surfaceHolder.unlockCanvasAndPost(c);
                        image.close();



                    }

                }
            },mBackgroundHandler);



        }

 protected void createCameraPreview() {
        try {

            captureRequestBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);

            captureRequestBuilder.addTarget(mImageReader.getSurface());
            cameraDevice.createCaptureSession(Arrays.asList(mImageReader.getSurface()), new CameraCaptureSession.StateCallback(){
                @Override
                public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
                    //The camera is already closed
                    if (null == cameraDevice) {
                        return;
                    }
                    // When the session is ready, we start displaying the preview.
                    cameraCaptureSessions = cameraCaptureSession;
                    updatePreview();
                }
                @Override
                public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {
                    Toast.makeText(MainActivity.this, "Configuration change", Toast.LENGTH_SHORT).show();
                }
            }, null);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

其余的都是一样的。当我显示这个我得到你可以在图片上看到的，但在第一个程序，当我直接在TextureView上显示YUV420_888，就像在第一个程序，一切都很好，但是当我做这个改变时，我得到了那些噪音。知道为什么吗？

编辑2： 整个代码：

package com.example.nikola.camera2project;


import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.hardware.camera2.CaptureResult;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.graphics.ImageFormat;
import android.graphics.SurfaceTexture;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.hardware.camera2.CameraMetadata;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.TotalCaptureResult;
import android.hardware.camera2.params.StreamConfigurationMap;
import android.media.Image;
import android.media.ImageReader;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.HandlerThread;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.Size;
import android.util.SparseIntArray;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.TextureView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback {

    private static final String TAG = "AndroidCameraApi";
    private TextureView textureView;
    private static final SparseIntArray ORIENTATIONS = new SparseIntArray();
    static {
        ORIENTATIONS.append(Surface.ROTATION_0, 90);
        ORIENTATIONS.append(Surface.ROTATION_90, 0);
        ORIENTATIONS.append(Surface.ROTATION_180, 270);
        ORIENTATIONS.append(Surface.ROTATION_270, 180);
    }
    private String cameraId;
    protected CameraDevice cameraDevice;
    protected CameraCaptureSession cameraCaptureSessions;
    protected CaptureRequest.Builder captureRequestBuilder;
    private Size imageDimension;
    private ImageReader imageReader;
    private File file;
    private static final int REQUEST_CAMERA_PERMISSION = 200;

    SurfaceView surfaceView;
    SurfaceHolder surfaceHolder;
    private Handler mBackgroundHandler;
    private HandlerThread mBackgroundThread;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_main);
        surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
        assert surfaceView != null;
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        imageReader = ImageReader.newInstance(480,640, ImageFormat.YUV_420_888,10);




    }



    private final CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {
        @Override
        public void onOpened(CameraDevice camera) {
            //This is called when the camera is open
            Log.e(TAG, "onOpened");
            cameraDevice = camera;
            createCameraPreview();
            imageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() {
                @Override
                public void onImageAvailable(ImageReader reader) {
                    Image image =  reader.acquireLatestImage();
                    if(image != null) {
                        ByteBuffer buffer0 = image.getPlanes()[0].getBuffer();
                        byte[] Y = new byte[buffer0.remaining()];
                        buffer0.get(Y);
                        byte[] Bits = new byte[Y.length * 4]; //That's where the RGBA array goes.
                        for (int i = 0; i < Y.length; i++) {
                            Bits[i * 4] =
                                    Bits[i * 4 + 1] =
                                            Bits[i * 4 + 2] = Y[i];
                            Bits[i * 4 + 3] = -1;//0xff, that's the alpha.
                        }
                        Bitmap bm = Bitmap.createBitmap(image.getWidth(), image.getHeight(), Bitmap.Config.ARGB_8888);
                        bm.copyPixelsFromBuffer(ByteBuffer.wrap(Bits));
                        Bitmap scaled = Bitmap.createScaledBitmap(bm, (int) (surfaceView.getHeight() * 1.33333), surfaceView.getHeight(), true);
                        Canvas c;
                        c = surfaceHolder.lockCanvas();
                        c.drawBitmap(scaled, 0, 0, null);
                        surfaceHolder.unlockCanvasAndPost(c);
                        image.close();



                    }

                }
            },mBackgroundHandler);

        }
        @Override
        public void onDisconnected(CameraDevice camera) {
            cameraDevice.close();
        }
        @Override
        public void onError(CameraDevice camera, int error) {
            cameraDevice.close();
            cameraDevice = null;
        }
    };
    protected void startBackgroundThread() {
        mBackgroundThread = new HandlerThread("Camera Background");
        mBackgroundThread.start();
        mBackgroundHandler = new Handler(mBackgroundThread.getLooper());
    }
    protected void stopBackgroundThread() {
        mBackgroundThread.quitSafely();
        try {
            mBackgroundThread.join();
            mBackgroundThread = null;
            mBackgroundHandler = null;
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    protected void createCameraPreview() {
        try {
            captureRequestBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
             captureRequestBuilder.addTarget(imageReader.getSurface());
           cameraDevice.createCaptureSession(Arrays.asList(imageReader.getSurface()), new CameraCaptureSession.StateCallback(){
                @Override
                public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
                    //The camera is already closed
                    if (null == cameraDevice) {
                        return;
                    }
                    // When the session is ready, we start displaying the preview.
                    cameraCaptureSessions = cameraCaptureSession;
                    updatePreview();
                }
                @Override
                public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {
                    Toast.makeText(MainActivity.this, "Configuration change", Toast.LENGTH_SHORT).show();
                }
            }, null);


        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }
    private void openCamera() {
        CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
        Log.e(TAG, "is camera open");
        try {
            cameraId = manager.getCameraIdList()[0];
            CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);
            StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
            assert map != null;
            imageDimension = map.getOutputSizes(SurfaceTexture.class)[0];
            // Add permission for camera and let user grant the permission
            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CAMERA_PERMISSION);
                return;
            }
            manager.openCamera(cameraId, stateCallback, null);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
        Log.e(TAG, "openCamera X");
    }
    protected void updatePreview() {
        if(null == cameraDevice) {
            Log.e(TAG, "updatePreview error, return");
        }
        captureRequestBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
        try {
            cameraCaptureSessions.setRepeatingRequest(captureRequestBuilder.build(), null, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        if (requestCode == REQUEST_CAMERA_PERMISSION) {
            if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
                // close the app
                Toast.makeText(MainActivity.this, "Sorry!!!, you can't use this app without granting permission", Toast.LENGTH_LONG).show();
                finish();
            }
        }
    }
    @Override
    protected void onResume() {
        super.onResume();
        Log.e(TAG, "onResume");
        startBackgroundThread();
    }
    @Override
    protected void onPause() {
        Log.e(TAG, "onPause");
        //closeCamera();
        stopBackgroundThread();
        super.onPause();
    }




    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        openCamera();
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {

    }
}

1 个答案:

答案 0 :(得分：1)

由于相机的硬件限制，可能是量化噪音。如果表面光线昏暗，相机可能会使用自动亮度调节和/或白平衡来使场景更加清晰。如果相机不具有可调节光圈，可调节快门或高分辨率ADC，则它将以数字方式进行调整，例如，通过将“Y”值乘以整数系数（对于每个像素）。因此，量化噪声。

通过调整AWB mode，您可以获得更好的结果。更好的照明可能有所帮或者，您可以在边缘检测算法中调整阈值。

修改

在surfaceHolder.setFormat(PixelFormat.RGBA_8888)来电后立即拨打addCallback()电话。

事实证明这实际上是表面默认内部格式的结果，它比ARGB_8888小。也发生在S6上。

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