Question

我正在开发API 7（2.1）。我实现了这样的相机视图：

public class CameraView extends SurfaceView implements SurfaceHolder.Callback {
SurfaceHolder mHolder;

int width;
int height;

Camera mCamera;

public CameraView(Context context, AttributeSet attrs) {
    super(context, attrs);
    initHolder();
}

public CameraView(Context context) {
    super(context);
    initHolder();
}

private void initHolder() {
    // Install a SurfaceHolder.Callback so we get notified when the
    // underlying surface is created and destroyed.
    mHolder = getHolder();
    mHolder.addCallback(this);
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}

public void surfaceCreated(SurfaceHolder holder) {
    // The Surface has been created, acquire the camera and tell it where to
    // draw.
    mCamera = Camera.open();

//      Parameters params = mCamera.getParameters();
//      // If we aren't landscape (the default), tell the camera we want
//      // portrait mode
//      if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
//          params.set("orientation", "portrait"); // "landscape"
//          // And Rotate the final picture if possible
//          // This works on 2.0 and higher only
//          // params.setRotation(90);
//          // Use reflection to see if it exists and to call it so you can
//          // support older versions
//          try {
//              Method rotateSet = Camera.Parameters.class.getMethod("setRotation", new Class[] { Integer.TYPE });
//              Object arguments[] = new Object[] { new Integer(90) };
//              rotateSet.invoke(params, arguments);
//          } catch (NoSuchMethodException nsme) {
//              // Older Device
//              Log.v("CAMERAVIEW", "No Set Rotation");
//          } catch (IllegalArgumentException e) {
//              Log.v("CAMERAVIEW", "Exception IllegalArgument");
//          } catch (IllegalAccessException e) {
//              Log.v("CAMERAVIEW", "Illegal Access Exception");
//          } catch (InvocationTargetException e) {
//              Log.v("CAMERAVIEW", "Invocation Target Exception");
//          }
//      }
//      mCamera.setParameters(params);
    setDisplayOrientation(mCamera, 90);

    try {
        mCamera.setPreviewDisplay(holder);
    } catch (IOException exception) {
        mCamera.release();
        mCamera = null;
    }
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // Surface will be destroyed when we return, so stop the preview.
    // Because the CameraDevice object is not a shared resource, it's very
    // important to release it when the activity is paused.
    mCamera.stopPreview();
    mCamera.release();
    mCamera = null;
}

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

    mCamera.startPreview();
}

public void takePicture(Camera.ShutterCallback shutter, Camera.PictureCallback raw, Camera.PictureCallback jpeg) {
    mCamera.takePicture(shutter, raw, jpeg);
}

protected void setDisplayOrientation(Camera camera, int angle){
    Method downPolymorphic;
    try {
        downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[] { int.class });
        if (downPolymorphic != null) {
            downPolymorphic.invoke(camera, new Object[] { angle });
        }

    } catch (Exception e1) {}
}
}

只有使用反射的方法（取自Williew在Android camera rotate中的答案）才能在我的设备上以正确的旋转显示预览，否则，预览总是旋转-90°

到目前为止一直很好，但现在我还有另外一个问题。当我使用activitie的回调获取位图时：

public void onPictureTaken(byte[] data, Camera camera) {
    Bitmap b = BitmapFactory.decodeByteArray(data, 0, data.length);

    Log.d("test", "---width: "  + b.getWidth() + " height: " + b.getHeight());
}

它始终处于横向模式！（在这种情况下2560 x 1920）。因此，如果用户在纵向模式下拍摄设备的照片，我得到一个位图2560 x 1920，无论如何，无论如何，当我放入图像视图时，由于某种原因看起来与我拍摄的肖像照片完全相同。问题出现在用户拍摄设备处于横向模式的照片时，我想旋转它，以便以纵向模式显示结果（按比例缩小） - 或者为风景照片做一些其他特殊操作。

但是我无法将它们与肖像照片区分开来，因为位图的尺寸是相同的：/

如何识别肖像/风景图片？

任何想法......？我是相机的新手，有点失落...... 提前谢谢。

修改好吧，我认为没有问题，尺寸总是一样的，因为无论我如何握住设备，图片实际上总是具有相同的尺寸。只有我不明白的是为什么我总是得到宽度＆gt;预览和图片明显处于纵向模式时的高度。

使用相机的位图尺寸（自定义视图）

0 个答案: