Android相机预览肖像比例

Question

Please help to make proper configuration of Android camera (testing on HTC Desire 2.3.3) to preview from camera in rotated (portrait) mode. Preview have to take less than a half of screen, it width have to be equal to device width, and scale have to be set dynamically according to camera aspect ratio. My current code:

public class CameraSurface extends SurfaceView implements SurfaceHolder.Callback {
…
public void surfaceCreated(SurfaceHolder holder) {
try {
    if (camera != null) {
                try {
                    camera.stopPreview();
                } catch (Exception ignore) {
                }
                try {
                    camera.release();
                } catch (Exception ignore) {
                }
                camera = null;
            }

            camera = Camera.open();             
            camera.setPreviewDisplay(holder);
        } catch (Exception ex) {
            try {
                if (camera != null) {
                    try {
                        camera.stopPreview();
                    } catch (Exception ignore) {
                    }
                    try {
                        camera.release();
                    } catch (Exception ignore) {
                    }
                    camera = null;
                }
            } catch (Exception ignore) {    
            }
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        try {
            if (camera != null) {
                try {
                    camera.stopPreview();
                } catch (Exception ignore) {
                }
                try {
                    camera.release();
                } catch (Exception ignore) {
                }
                camera = null;
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }


    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        try {
            Camera.Parameters parameters = camera.getParameters();
            float bff = 0;
            try {
                List<Camera.Size> supportedSizes = null;

                //maximize supported resizes, TODO remove as hardcode
                w*=1.5;
                h*=1.5;

                // On older devices (<1.6) the following will fail
                // the camera will work nevertheless
                supportedSizes = Compatibility.getSupportedPreviewSizes(parameters);

                // preview form factor
                float ff = (float) w / h;
                Log.d("TAG", "Screen res: w:" + w + " h:" + h
                        + " aspect ratio:" + ff);

                // holder for the best form factor and size                 
                int bestw = 0;
                int besth = 0;
                Iterator<Camera.Size> itr = supportedSizes.iterator();

                // we look for the best preview size, it has to be the closest
                // to the
                // screen form factor

                while (itr.hasNext()) {
                    Camera.Size element = itr.next();
                    // current form factor
                    float cff = (float) element.width / element.height;
                    // check if the current element is a candidate to replace
                    // the best match so far
                    // current form factor should be closer to the bff
                    // preview width should be less than screen width
                    // preview width should be more than current bestw
                    // this combination will ensure that the highest resolution
                    // will win
                    Log.d("TAG", "Candidate camera element: w:"
                            + element.width + " h:" + element.height
                            + " aspect ratio:" + cff);
                    if ((ff - cff <= ff - bff) && (element.width <= w)
                            && (element.width >= bestw)) {
                        bff = cff;
                        bestw = element.width;
                        besth = element.height;
                    }
                }
                Log.d("TAG", "Chosen camera element: w:" + bestw + " h:"
                        + besth + " aspect ratio:" + bff);
                // Some Samsung phones will end up with bestw and besth = 0
                // because their minimum preview size is bigger then the screen
                // size.
                // In this case, we use the default values: 480x320
                if ((bestw == 0) || (besth == 0)) {
                    Log.d("Mixare", "Using default camera parameters!");
                    bestw = 480;
                    besth = 320;
                }               
                parameters.setPreviewSize(bestw,besth);
            } catch (Exception ex) {
                parameters.setPreviewSize(480,320);

                bff=1.5f;
            }
            makeResizeForCameraAspect(bff);                     
            camera.setDisplayOrientation(90);//only Android 2.2 and later
            camera.setParameters(parameters);               
            camera.startPreview();
        } catch (Exception ex) {
            Log.e(TAG,"",ex);
        }
    }

    private void makeResizeForCameraAspect(float cameraAspectRatio){
        LayoutParams layoutParams=this.getLayoutParams();
        int matchParentWidth=this.getWidth();           
        int newHeight=(int)(matchParentWidth/cameraAspectRatio);
        if(newHeight!=layoutParams.height){
            layoutParams.height=newHeight;
            layoutParams.width=matchParentWidth;    
            this.setLayoutParams(layoutParams);
            this.invalidate();
        }
    }
}

Activity layout:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >  
    <org.mixare.CameraSurface
        android:id="@+id/camera_surface"
        android:layout_width="match_parent"
        android:layout_height="150dp"
        android:layout_alignParentTop="true"

         />
    <!--CameraSurface layout_height will be changed during it's loading process -->
</RelativeLayout>

AndroidManifest configured to portrait:

  <activity android:label="@string/app_name" android:name=".MixView" 
    android:screenOrientation="portrait"  
    android:launchMode="singleTop" >

actual images:

- device rotated portrait

- device rotated landscape

Found in the same topics: Android - Camera preview is sideways , Android camera rotate , but I've got same result with their code

And here you could see wrong proportions of the image. How make to show in proper proportions rotated & scaled camera preview?

Parts of code were taken from Mixare Open Source project, http://www.mixare.org/

Answer 1

I know I am too late to answer this, but this issue can be fixed by setting display orientation of camera to 90 degrees ie by adding following line after camera.open() in SurfaceCreated method of CameraSurface class

camera.setDisplayOrientation(90);

Hope this helps others having the same issue.