Android相机产生的图像捕获后应该旋转吗？

Question

我正在编写一个使用相机的Android应用程序。 我将相机显示方向设置为90，我的活动是纵向：

camera.setDisplayOrientation(90);

我得到的是定向良好的预览图片，但是生成的图像旋转到-90度（逆时针），并且

exif.getAttribute(ExifInterface.TAG_ORIENTATION)

返回ORIENTATION_NORMAL
这是预期的行为吗？ 捕获后是否应该旋转结果图像？

设备-Nexus S，API-10

Answer 1

尝试这个

try {
        File f = new File(imagePath);
        ExifInterface exif = new ExifInterface(f.getPath());
        int orientation = exif.getAttributeInt(
                ExifInterface.TAG_ORIENTATION,
                ExifInterface.ORIENTATION_NORMAL);

        int angle = 0;

        if (orientation == ExifInterface.ORIENTATION_ROTATE_90) {
            angle = 90;
        } else if (orientation == ExifInterface.ORIENTATION_ROTATE_180) {
            angle = 180;
        } else if (orientation == ExifInterface.ORIENTATION_ROTATE_270) {
            angle = 270;
        }

        Matrix mat = new Matrix();
        mat.postRotate(angle);
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inSampleSize = 2;

        Bitmap bmp = BitmapFactory.decodeStream(new FileInputStream(f),
                null, options);
        bitmap = Bitmap.createBitmap(bmp, 0, 0, bmp.getWidth(),
                bmp.getHeight(), mat, true);
        ByteArrayOutputStream outstudentstreamOutputStream = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.PNG, 100,
                outstudentstreamOutputStream);
        imageView.setImageBitmap(bitmap);

    } catch (IOException e) {
        Log.w("TAG", "-- Error in setting image");
    } catch (OutOfMemoryError oom) {
        Log.w("TAG", "-- OOM Error in setting image");
    }

会工作的

Answer 2

问题在于，由于OEM厂商不遵守该标准，因此相机定位完全是一场灾难（就像捕获图像一样）。 HTC手机以一种方式来做事，三星手机以另一种方式来做，无论哪家厂商，Nexus系列产品似乎都可以使用，无论哪种硬件，我都认为基于CM7的ROM遵循标准，但是您明白了。 您必须根据电话/ ROM确定要做什么。 请参阅此处的讨论： 某些设备的Android相机在拍摄时无法解释的旋转（不在EXIF中）

Answer 3

我有和您一样的问题，但是我已经解决了。
您应该使用相同的代码：

Camera.Parameters parameters = camera.getParameters();
parameters.setRotation(90);
camera.setParameters(parameters);

我希望您也可以使用此代码。

Answer 4

camera.setDisplayOrientation(90);

我已将应用程序编码为仅纵向模式。

将使相机旋转到90度，这可能会导致它不适用于android中的所有设备。要获取所有android设备的正确预览，请使用开发者网站中引用的以下代码。

在下面，您必须发送您的活动，cameraId = back为0，而Front camera为1

public static void setCameraDisplayOrientation(Activity activity, int cameraId, android.hardware.Camera camera) {
    android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
    android.hardware.Camera.getCameraInfo(cameraId, info);
    int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
    int degrees = 0;
    switch (rotation) {
        case Surface.ROTATION_0:
            degrees = 0;
            break;
        case Surface.ROTATION_90:
            degrees = 90;
            break;
        case Surface.ROTATION_180:
            degrees = 180;
            break;
        case Surface.ROTATION_270:
            degrees = 270;
            break;
    }

   int result;
    //int currentapiVersion = android.os.Build.VERSION.SDK_INT;
        // do something for phones running an SDK before lollipop
        if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
            result = (info.orientation + degrees) % 360;
            result = (360 - result) % 360; // compensate the mirror
        } else { // back-facing
            result = (info.orientation - degrees + 360) % 360;
        }

    camera.setDisplayOrientation(result);
} 

这是设置摄像机的setDisplayOrientation的方法

现在，您可能有麻烦以正确的方向保存捕获的图像，这是Camera API中的错误，无法支持android中的所有设备。 您可以使用以下步骤克服

请注意，附加值将无法在所有设备中提供正确的价值，因此这对您有帮助

int CameraEyeValue = setPhotoOrientation(CameraActivity.this, cameraFront==true ? 1:0); // CameraID = 1 : front 0:back

通过使用之前用于DisplayOrientation的相同概念

public int setPhotoOrientation(Activity activity, int cameraId) {
    android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
    android.hardware.Camera.getCameraInfo(cameraId, info);
    int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
    int degrees = 0;
    switch (rotation) {
        case Surface.ROTATION_0:
            degrees = 0;
            break;
        case Surface.ROTATION_90:
            degrees = 90;
            break;
        case Surface.ROTATION_180:
            degrees = 180;
            break;
        case Surface.ROTATION_270:
            degrees = 270;
            break;
    }

    int result;
    // do something for phones running an SDK before lollipop
    if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
        result = (info.orientation + degrees) % 360;
        result = (360 - result) % 360; // compensate the mirror
    } else { // back-facing
        result = (info.orientation - degrees + 360) % 360;
    }

    return result;
}

因此，您最终的PictureCallBack方法应类似于

private PictureCallback getPictureCallback() {
    PictureCallback picture = new PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            //make a new picture file
            File pictureFile = getOutputMediaFile();

            if (pictureFile == null) {
                return;
            }
            try {
                //write the file
                FileOutputStream fos = new FileOutputStream(pictureFile);
                Bitmap bm=null;

                // COnverting ByteArray to Bitmap - >Rotate and Convert back to Data
                if (data != null) {
                    int screenWidth = getResources().getDisplayMetrics().widthPixels;
                    int screenHeight = getResources().getDisplayMetrics().heightPixels;
                    bm = BitmapFactory.decodeByteArray(data, 0, (data != null) ? data.length : 0);

                    if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
                        // Notice that width and height are reversed
                        Bitmap scaled = Bitmap.createScaledBitmap(bm, screenHeight, screenWidth, true);
                        int w = scaled.getWidth();
                        int h = scaled.getHeight();
                        // Setting post rotate to 90
                        Matrix mtx = new Matrix();

                        int CameraEyeValue = setPhotoOrientation(AndroidCameraExample.this, cameraFront==true ? 1:0); // CameraID = 1 : front 0:back
                        if(cameraFront) { // As Front camera is Mirrored so Fliping the Orientation
                            if (CameraEyeValue == 270) {
                                mtx.postRotate(90);
                            } else if (CameraEyeValue == 90) {
                                mtx.postRotate(270);
                            }
                        }else{
                                mtx.postRotate(CameraEyeValue); // CameraEyeValue is default to Display Rotation
                        }

                        bm = Bitmap.createBitmap(scaled, 0, 0, w, h, mtx, true);
                    }else{// LANDSCAPE MODE
                        //No need to reverse width and height
                        Bitmap scaled = Bitmap.createScaledBitmap(bm, screenWidth, screenHeight, true);
                        bm=scaled;
                    }
                }
                // COnverting the Die photo to Bitmap



                ByteArrayOutputStream stream = new ByteArrayOutputStream();
                bm.compress(Bitmap.CompressFormat.JPEG, 100, stream);
                byte[] byteArray = stream.toByteArray();
                fos.write(byteArray);
                //fos.write(data);
                fos.close();

                Toast toast = Toast.makeText(myContext, "Picture saved: " + pictureFile.getName(), Toast.LENGTH_LONG);
                toast.show();

            } catch (FileNotFoundException e) {
            } catch (IOException e) {
            }

            //refresh camera to continue preview
            mPreview.refreshCamera(mCamera);
            mPreview.setCameraDisplayOrientation(CameraActivity.this,GlobalCameraId,mCamera);
        }
    };
    return picture;
}

由于使用前置和后置摄像头仅适用于纵向模式，因此在所有android设备中，图片均被旋转为仅纵向模式且具有正确的纵向方向。

对于LandScape，您可以将此作为参考并在下面的块中进行更改

   if(cameraFront) { // As Front camera is Mirrored so Fliping the Orientation
         if (CameraEyeValue == 270) {
             mtx.postRotate(90); //change Here 
          } else if (CameraEyeValue == 90) {
             mtx.postRotate(270);//change Here 
           }
        }else{
           mtx.postRotate(CameraEyeValue); // CameraEyeValue is default to Display Rotation //change Here 
        }