我正在捕捉图像并将其设置为图像视图。

public void captureImage() {

    Intent intentCamera = new Intent("android.media.action.IMAGE_CAPTURE");
    File filePhoto = new File(Environment.getExternalStorageDirectory(), "Pic.jpg");
    imageUri = Uri.fromFile(filePhoto);
    MyApplicationGlobal.imageUri = imageUri.getPath();
    intentCamera.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
    startActivityForResult(intentCamera, TAKE_PICTURE);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intentFromCamera) {
    super.onActivityResult(requestCode, resultCode, intentFromCamera);

    if (resultCode == RESULT_OK && requestCode == TAKE_PICTURE) {

        if (intentFromCamera != null) {
            Bundle extras = intentFromCamera.getExtras();
            if (extras.containsKey("data")) {
                bitmap = (Bitmap) extras.get("data");
            }
            else {
                bitmap = getBitmapFromUri();
            }
        }
        else {
            bitmap = getBitmapFromUri();
        }
        // imageView.setImageBitmap(bitmap);
        imageView.setImageURI(imageUri);
    }
    else {
    }
}

public Bitmap getBitmapFromUri() {

    getContentResolver().notifyChange(imageUri, null);
    ContentResolver cr = getContentResolver();
    Bitmap bitmap;

    try {
        bitmap = android.provider.MediaStore.Images.Media.getBitmap(cr, imageUri);
        return bitmap;
    }
    catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}

但问题是,某些设备上的图像每次旋转时。例如,在三星设备上,它工作得很好,但在索尼Xperia上,图像旋转了90度,在东芝Thrive(平板电脑)上旋转了180度。


当前回答

这里的解决方案基于上面的解决方案,但只需要上下文和图像文件作为输入

public static Bitmap rectifyImage(Context context,File imageFile){
    Bitmap originalBitmap= BitmapFactory.decodeFile(imageFile.getAbsolutePath());
    try{
        Uri uri=Uri.fromFile(imageFile);
        InputStream input = context.getContentResolver().openInputStream(uri);
        ExifInterface ei;
        
        if (Build.VERSION.SDK_INT > 23)
            ei = new ExifInterface(input);
        else
            ei = new ExifInterface(uri.getPath());

        int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
        switch (orientation) {
            case ExifInterface.ORIENTATION_ROTATE_90:
                return rotateImage(originalBitmap, 90);
            case ExifInterface.ORIENTATION_ROTATE_180:
                return rotateImage(originalBitmap, 180);
            case ExifInterface.ORIENTATION_ROTATE_270:
                return rotateImage(originalBitmap, 270);
            default:
                return originalBitmap;
        }
    }catch (Exception e){
        return originalBitmap;
    }
}

public static Bitmap rotateImage(Bitmap source, float angle) {
    Matrix matrix = new Matrix();
    matrix.postRotate(angle);
    return Bitmap.createBitmap(source, 0, 0, source.getWidth(), source.getHeight(),
            matrix, true);
}

其他回答

首先,你应该知道,自Android 7.0以来,我们必须使用FileProvider和ContentUri,否则你会得到一个烦人的错误,试图调用你的意图。这是示例代码:

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, getUriFromPath(context, "[Your path to save image]"));
startActivityForResult(intent, CAPTURE_IMAGE_RESULT);

方法getUriFromPath(Context, String)基于用户版本的Android创建FileUri (file://…)或ContentUri (content://…)

public Uri getUriFromPath(Context context, String destination) {
    File file =  new File(destination);

    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
        return FileProvider.getUriForFile(context, context.getPackageName() + ".provider", file);
    } else {
        return Uri.fromFile(file);
    }
}

onActivityResult后,你可以捕捉图像被相机保存的uri,但现在你必须检测相机旋转,这里我们将使用修改后的@Jason Robinson回答:

首先,我们需要基于Uri创建ExifInterface

@Nullable
public ExifInterface getExifInterface(Context context, Uri uri) {
    try {
        String path = uri.toString();
        if (path.startsWith("file://")) {
            return new ExifInterface(path);
        }
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            if (path.startsWith("content://")) {
                InputStream inputStream = context.getContentResolver().openInputStream(uri);
                return new ExifInterface(inputStream);
            }
        }
    }
    catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

上面的代码可以简化,但我想显示一切。因此,从FileUri我们可以创建基于字符串路径的ExifInterface,但从ContentUri我们不能,Android不支持。

在这种情况下,我们必须使用基于InputStream的其他构造函数。记住这个构造函数默认是不可用的,你必须添加额外的库:

compile "com.android.support:exifinterface:XX.X.X"

现在我们可以使用getExifInterface方法来获取我们的角度:

public float getExifAngle(Context context, Uri uri) {
    try {
        ExifInterface exifInterface = getExifInterface(context, uri);
        if(exifInterface == null) {
            return -1f;
        }

        int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,
                ExifInterface.ORIENTATION_UNDEFINED);

        switch (orientation) {
            case ExifInterface.ORIENTATION_ROTATE_90:
                return 90f;
            case ExifInterface.ORIENTATION_ROTATE_180:
                return 180f;
            case ExifInterface.ORIENTATION_ROTATE_270:
                return 270f;
            case ExifInterface.ORIENTATION_NORMAL:
                return 0f;
            case ExifInterface.ORIENTATION_UNDEFINED:
                return -1f;
            default:
                return -1f;
        }
    }
    catch (Exception e) {
        e.printStackTrace();
        return -1f;
    }
}

现在你有角度适当旋转你的图像。

这里的解决方案基于上面的解决方案,但只需要上下文和图像文件作为输入

public static Bitmap rectifyImage(Context context,File imageFile){
    Bitmap originalBitmap= BitmapFactory.decodeFile(imageFile.getAbsolutePath());
    try{
        Uri uri=Uri.fromFile(imageFile);
        InputStream input = context.getContentResolver().openInputStream(uri);
        ExifInterface ei;
        
        if (Build.VERSION.SDK_INT > 23)
            ei = new ExifInterface(input);
        else
            ei = new ExifInterface(uri.getPath());

        int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
        switch (orientation) {
            case ExifInterface.ORIENTATION_ROTATE_90:
                return rotateImage(originalBitmap, 90);
            case ExifInterface.ORIENTATION_ROTATE_180:
                return rotateImage(originalBitmap, 180);
            case ExifInterface.ORIENTATION_ROTATE_270:
                return rotateImage(originalBitmap, 270);
            default:
                return originalBitmap;
        }
    }catch (Exception e){
        return originalBitmap;
    }
}

public static Bitmap rotateImage(Bitmap source, float angle) {
    Matrix matrix = new Matrix();
    matrix.postRotate(angle);
    return Bitmap.createBitmap(source, 0, 0, source.getWidth(), source.getHeight(),
            matrix, true);
}

你可以像文档中的谷歌那样读取摄像头传感器的方向:https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html

SENSOR_ORIENTATION

Added in API level 21
Key<Integer> SENSOR_ORIENTATION
Clockwise angle through which the output image needs to be rotated to be upright on the device screen in its native orientation.

Also defines the direction of rolling shutter readout, which is from top to bottom in the sensor's coordinate system.

Units: Degrees of clockwise rotation; always a multiple of 90

Range of valid values:
0, 90, 180, 270

This key is available on all devices.

示例代码:

CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
int orientation = 0;
try {
    String cameraId = manager.getCameraIdList()[0];
    CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);
    orientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);
}
catch (Exception e)
{
}

最好试着以特定的方向照相。

android:screenOrientation="landscape"
android:configChanges="orientation|keyboardHidden"

为了获得最好的结果,在cameraview活动中给出景观方向。

Jason Robinson和Sami Eltamawy的回答非常棒。

只是为了完成该方法的改进,您应该使用compat ExifInterface。

com.android.support: exifinterface: $ {lastLibVersion}

你将能够实例化ExifInterface(pior API <24)与InputStream(从ContentResolver)而不是uri路径避免“文件未找到异常”

https://android-developers.googleblog.com/2016/12/introducing-the-exifinterface-support-library.html