android - HTC Desire HD 不接受带有 hardware.Camera 的 setParameter()

Question

我是一名学生，正在 Android 2.2 上开发一个项目。对于我的测试和应用程序执行，我使用 HTC Desire HD(配备 Android 2.2)。

我只想创建一个组合(类)来使用移动设备拍照。我有一个 Android 类，用于 getOptimalPreviewSize() 方法(此方法位于 ApiDemos 2.2 中)。此方法用于修复此类错误:

02-14 21:38:05.818: ERROR/AndroidRuntime(2884): java.lang.RuntimeException: Fail to connect to camera service
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.hardware.Camera.native_setup(Native Method)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.hardware.Camera.<init>(Camera.java:118)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.hardware.Camera.open(Camera.java:91)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at com.example.android.apis.graphics.Preview.surfaceCreated(CameraPreview.java:69)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.SurfaceView.updateWindow(SurfaceView.java:540)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.SurfaceView.dispatchDraw(SurfaceView.java:339)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewGroup.drawChild(ViewGroup.java:1660)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1389)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.View.draw(View.java:6764)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewGroup.drawChild(ViewGroup.java:1662)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1389)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.View.draw(View.java:6764)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1887)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewRoot.draw(ViewRoot.java:1422)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewRoot.performTraversals(ViewRoot.java:1167)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1744)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.os.Looper.loop(Looper.java:143)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at android.app.ActivityThread.main(ActivityThread.java:5068)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at java.lang.reflect.Method.invokeNative(Native Method)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at java.lang.reflect.Method.invoke(Method.java:521)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
02-14 21:38:05.818: ERROR/AndroidRuntime(2884):     at dalvik.system.NativeStart.main(Native Method)

所以，我用这段代码解决了这个问题:

public class CameraView extends Activity implements SurfaceHolder.Callback {

private SurfaceView mSurfaceView = null;
private SurfaceHolder mSurfaceHolder = null;
private Camera mCamera = null;
private boolean mPreviewRunning = false;    

public void onCreate(Bundle icicle) {
    super.onCreate(icicle);

    getWindow().setFormat(PixelFormat.TRANSLUCENT);
    //requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.camera_surface);
    mSurfaceView = (SurfaceView) findViewById(R.id.surface_camera);
    mSurfaceHolder = mSurfaceView.getHolder();
    mSurfaceHolder.addCallback(this);
    mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    if (!(android.os.Environment.getExternalStorageState().equals(
            android.os.Environment.MEDIA_MOUNTED))) 
    {
        Toast
        .makeText(CameraView.this, R.string.msgNoSdCard, Toast.LENGTH_LONG)
        .show();
    }
    else
    {
        Toast
        .makeText(CameraView.this, R.string.msgPressBackBt, Toast.LENGTH_LONG)
        .show();
    }
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
    // TODO Auto-generated method stub
    mCamera = Camera.open();
     try {
           mCamera.setPreviewDisplay(holder);
        } catch (IOException exception) {
            mCamera.release();
            mCamera = null;
            // TODO: add more exception handling logic here
        }
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    mCamera.stopPreview();
    mPreviewRunning = false;
    mCamera.release();
}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    //Handle the back button
    if ((keyCode == KeyEvent.KEYCODE_DPAD_CENTER) || (keyCode == KeyEvent.KEYCODE_CAMERA)){
        mCamera.takePicture(shutterCallback, rawCallback, jpegCallback);
        return true;
    }
    else {
        return super.onKeyDown(keyCode, event);
    }
}

ShutterCallback shutterCallback = new ShutterCallback() {       
    public void onShutter() {                       
    }   
};  


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

/** Handles data for jpeg picture */    
PictureCallback jpegCallback = new PictureCallback() {      
    public void onPictureTaken(byte[] data, Camera camera) {            
        FileOutputStream outStream = null;          
        try {               
            // write to local sandbox file system               
            //outStream =               
            //CameraView.this.openFileOutput(String.format("%d.jpg",                
            //System.currentTimeMillis()), 0);              
            // Or write to sdcard               
            long fileName = System.currentTimeMillis();
            outStream = new FileOutputStream(String.format(                     
                    "/sdcard/%d.jpg", fileName));               
            outStream.write(data);              
            outStream.close();              

            Intent resultIntent = new Intent();     
            String imageFileName = String.format("/sdcard/%d.jpg", fileName);
            resultIntent.putExtra("MyAvatar", imageFileName);
            setResult(Activity.RESULT_OK, resultIntent);


        } catch (FileNotFoundException e) {             
            e.printStackTrace();            
        } 
        catch (IOException e) {             
            e.printStackTrace();            
        } 
        finally {           
        }               
    }   
};

private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
    final double ASPECT_TOLERANCE = 0.05;
    double targetRatio = (double) w / h;
    if (sizes == null) return null;

    Size optimalSize = null;
    double minDiff = Double.MAX_VALUE;

    int targetHeight = h;

    // Try to find an size match aspect ratio and size
    for (Size size : sizes) {
        double ratio = (double) size.width / size.height;
        if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
        if (Math.abs(size.height - targetHeight) < minDiff) {
            optimalSize = size;
            minDiff = Math.abs(size.height - targetHeight);
        }
    }

    // Cannot find the one match the aspect ratio, ignore the requirement
    if (optimalSize == null) {
        minDiff = Double.MAX_VALUE;
        for (Size size : sizes) {
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }
    }
    return optimalSize;
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    // Now that the size is known, set up the camera parameters and begin
    // the preview.
    Camera.Parameters parameters = mCamera.getParameters();

    List<Size> sizes = parameters.getSupportedPreviewSizes();
    Size optimalSize = getOptimalPreviewSize(sizes, w, h);
    parameters.setPreviewSize(optimalSize.width, optimalSize.height);

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

}

最后一个问题是:如果设备正在显示相机 View ，则设备会完全迷失方向。如果我将相机指向房间的顶部(拍摄的场景)，屏幕就会向左移动，如果我将相机放在地面上，屏幕就会向右移动。横向屏幕也存在同样的问题，高度和宽度以及相机方向错误。

是否有解决方案可以解决 HTC Desire HD 的 Camera API 的此问题？

谢谢

相关链接:

Android 2.2 SDK - setParameters failed for Camera API on Nexus One

http://code.google.com/p/android/issues/detail?id=7909

Answer 1

问题不在于您的手机，而在于您为相机分辨率设置的参数。我在学习使用 Nexus One 上的相机时遇到了类似的问题。您需要获取适用于代码正在处理的手机的已知分辨率列表，并将其设置为其中之一。

你确定获取参数不起作用吗？你能发布不起作用的代码吗？也许你做错了。