我的相机预览显示错误，我需要将这张照片存储到SD卡中。如何操作？

Question

这个相机程序在我们垂直观看时显示水平预览，就像它正在显示90度角度一样，并且它没有存储到我的SD卡中。有人能帮我如何改变我的视角并将其更改为SD卡吗？

1.我的预览类：

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.hardware.Camera;
import android.hardware.Camera.PreviewCallback;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
class Preview extends SurfaceView implements SurfaceHolder.Callback {
    private static final String TAG = "Preview";
    SurfaceHolder mHolder;
    public Camera camera;
     Preview(Context context) {
        super(context);
        mHolder = getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void surfaceCreated(SurfaceHolder holder) {
        camera = Camera.open();
        try {
            camera.setPreviewDisplay(holder);


            camera.setPreviewCallback(new PreviewCallback() {

                public void onPreviewFrame(byte[] data, Camera arg1) {
                    FileOutputStream outStream = null;
                    try {
                        outStream = new FileOutputStream(String.format("/sdcard/%d.jpg", System.currentTimeMillis()));  
                        outStream.write(data);
                        outStream.close();
                        Log.d(TAG, "onPreviewFrame - wrote bytes: " + data.length);
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    } finally {
                    }
                        Preview.this.invalidate();
                }
            });
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        camera.stopPreview();
        camera = null;
    }
        Camera.Parameters parameters = camera.getParameters();
        parameters.setPreviewSize(w, h);
        camera.setParameters(parameters);
        camera.startPreview();
    }

    @Override
    public void draw(Canvas canvas) {
            super.draw(canvas);
            Paint p= new Paint(Color.RED);
            Log.d(TAG,"draw");
            canvas.drawText("PREVIEW", canvas.getWidth()/2, canvas.getHeight()/2, p );
    }
}

2. MYCameraDemo类

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.FrameLayout;
public class CameraDemo extends Activity {
    private static final String TAG = "CameraDemo";
    Camera camera;
    Preview preview;
    Button buttonClick;

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

        preview = new Preview(this);
        ((FrameLayout) findViewById(R.id.preview)).addView(preview);

        buttonClick = (Button) findViewById(R.id.buttonClick);
        buttonClick.setOnClickListener( new OnClickListener() {
            public void onClick(View v) {
                preview.camera.takePicture(shutterCallback, rawCallback, jpegCallback);
            }
        });

        Log.d(TAG, "onCreate'd");
    }
    ShutterCallback shutterCallback = new ShutterCallback() {
        public void onShutter() {
            Log.d(TAG, "onShutter'd");
        }
    };

    /** Handles data for raw picture */
    PictureCallback rawCallback = new PictureCallback() {
        public void onPictureTaken(byte[] data, Camera camera) {
            Log.d(TAG, "onPictureTaken - raw");
        }
    };

    PictureCallback jpegCallback = new PictureCallback() {
        public void onPictureTaken(byte[] data, Camera camera) {
            FileOutputStream outStream = null;
            try {
                        outStream = CameraDemo.this.openFileOutput(String.format("%d.jpg", System.currentTimeMillis()), 0); 

                outStream = new FileOutputStream(String.format("/sdcard/%d.jpg", System.currentTimeMillis()));  
                outStream.write(data);
                outStream.close();
                Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
            }
            Log.d(TAG, "onPictureTaken - jpeg");
        }
    };
}

- Crishnan Kandada

---

最后……你做了什么……我也遇到了同样的问题……？ - Kalpesh

Answer 1

也许这个链接可以帮助您。

http://adblogcat.com/a-camera-preview-with-a-bounding-box-like-google-goggles/

这是onSurfaceChange方法，它设置正确的方向。

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    //Log.i(TAG, "Preview: surfaceChanged() - size now " + w + "x" + h);
    // Now that the size is known, set up the camera parameters and begin
    // the preview.
    try {
        mParameters = mCamera.getParameters();
        mParameters.set("orientation","landscape");
        for (Integer i : mParameters.getSupportedPreviewFormats()) {
            //Log.i(TAG, "supported preview format: " + i);
        }

        List<Size> sizes = mParameters.getSupportedPreviewSizes();
        for (Size size : sizes) {
            //Log.i(TAG, "supported preview size: " + size.width + "x" + size.height);
        }
        mCamera.setParameters(mParameters); // apply the changes
    } catch (Exception e) {
        // older phone - doesn't support these calls
    }

    //updateBufferSize(); // then use them to calculate

    Size p = mCamera.getParameters().getPreviewSize();
    //Log.i(TAG, "Preview: checking it was set: " + p.width + "x" + p.height); // DEBUG
    mCamera.startPreview();
}

public Parameters getCameraParameters(){
    return mCamera.getParameters();
}

这篇文章将参数设置为横向。我看到你的代码中没有这个。

此外，对于保存图像，我看到有两种方法：

private boolean savePhoto(Bitmap bm) {
FileOutputStream image = null;
try {
    image = new FileOutputStream(mLocation);
} catch (FileNotFoundException e) {
    e.printStackTrace();
}
bm.compress(CompressFormat.JPEG, 100, image);
if (bm != null) {
    int h = bm.getHeight();
    int w = bm.getWidth();
    //Log.i(TAG, "savePhoto(): Bitmap WxH is " + w + "x" + h);
} else {
    //Log.i(TAG, "savePhoto(): Bitmap is null..");
    return false;
}
return true;

}

并且

public Bitmap getPic(int x, int y, int width, int height) {
System.gc();
Bitmap b = null;
Size s = mParameters.getPreviewSize();

YuvImage yuvimage = new YuvImage(mBuffer, ImageFormat.NV21, s.width, s.height, null);
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
yuvimage.compressToJpeg(new Rect(x, y, width, height), 100, outStream); // make JPG
b = BitmapFactory.decodeByteArray(outStream.toByteArray(), 0, outStream.size());
if (b != null) {
    //Log.i(TAG, "getPic() WxH:" + b.getWidth() + "x" + b.getHeight());
} else {
    //Log.i(TAG, "getPic(): Bitmap is null..");
}
yuvimage = null;
outStream = null;
System.gc();
return b;

}

你需要使用Android 2.2版本。

- Juan Acevedo