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);

我的预览图片很好，但生成的图像旋转到-90度（逆时针）并且

exif.getAttribute(ExifInterface.TAG_ORIENTATION)

返回ORIENTATION_NORMAL
这是预期的行为吗？我应该在捕获后旋转结果图像吗？

设备 - Nexus S，API - 10

Answer 1

试试这个

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");
    }

它会起作用

Answer 2

问题是相机方向是一个彻底的灾难（就像捕获图像一样），因为OEM不遵守标准。 HTC手机以一种方式做事，三星手机以不同的方式做事，Nexus系列似乎坚持无论哪家供应商，基于CM7的ROM我认为无论哪种硬件都遵循标准，但你明白了。你必须根据手机/ ROM确定要做什么。请参阅此处的讨论：Android camera unexplainable rotation on capture for some devices (not in EXIF)

Answer 3

我遇到了和你一样的问题，但我已经解决了。
您应该使用相同的代码：

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

我希望你也可以使用这个代码。

Answer 4

camera.setDisplayOrientation(90);

我只为纵向模式编写了应用程序。

会使相机旋转到90度，这可能导致不适合Android中的所有设备为了获得所有Android设备的正确预览，请使用以下代码，这些代码在开发人员站点中被引用。

下面你必须发送你的活动，cameraId = back是0而前置摄像头是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);
}

这是为相机

设置setDisplayOrientation的方法

现在您可能遇到的问题是以正确的方向保存捕获的图像，这是Camera API中的错误，以支持Android中的所有设备。您可以使用以下步骤克服

PLS注意EXIF值不会给你所有设备的正确值，所以这会对你有所帮助

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

使用我们之前用于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;
}

所以你的最终PictureCallBack方法看起来应该是

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;
}

由于仅适用于使用前置和后置相机的纵向模式在所有Android设备中，图像被旋转为仅纵向模式，并且具有正确的纵向方向。

对于LandScape，您可以将其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 
        }

Android相机产生的图像应该在捕获后旋转？

4 个答案: