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

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)
{
}

其他回答

下面的代码与我一起工作,它从fileUri获得位图,并在需要时进行旋转固定:

    private fun getCapturedImage(selectedPhotoUri: Uri): Bitmap {
        val bitmap = when {
            Build.VERSION.SDK_INT < 28 -> MediaStore.Images.Media.getBitmap(
                this.contentResolver,
                selectedPhotoUri
            )
            else -> {
                val source = ImageDecoder.createSource(this.contentResolver, selectedPhotoUri)
                ImageDecoder.decodeBitmap(source)
            }
        }

        // If the image is rotated, fix it
        return when (ExifInterface(contentResolver.run { openInputStream(selectedPhotoUri) }).getAttributeInt(
            ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_UNDEFINED)) {
            ExifInterface.ORIENTATION_ROTATE_90 ->
                Bitmap.createBitmap(bitmap, 0, 0, bitmap.width, bitmap.height, Matrix().apply {
                    postRotate(90F) }, true)
            ExifInterface.ORIENTATION_ROTATE_180 ->
                Bitmap.createBitmap(bitmap, 0, 0, bitmap.width, bitmap.height, Matrix().apply {
                    postRotate(180F) }, true)
            ExifInterface.ORIENTATION_ROTATE_270 ->
                Bitmap.createBitmap(bitmap, 0, 0, bitmap.width, bitmap.height, Matrix().apply {
                    postRotate(270F) }, true)
            else -> bitmap
        } 
    }

通过将Jason Robinson的回答与Felix的回答结合起来,并填补缺失的部分,这里是这个问题的最终完整解决方案,将在Android Android 4.1 (Jelly Bean), Android 4.4 (KitKat)和Android 5.0 (Lollipop)上进行测试后完成以下工作。

步骤

如果图像大于1024x1024,则缩小图像。 仅当图像旋转90度、180度或270度时,才将其旋转到正确的方向。 为了内存的目的,回收旋转的图像。

下面是代码部分:

使用当前Context和要修复的图像URI调用以下方法

/**
 * This method is responsible for solving the rotation issue if exist. Also scale the images to
 * 1024x1024 resolution
 *
 * @param context       The current context
 * @param selectedImage The Image URI
 * @return Bitmap image results
 * @throws IOException
 */
public static Bitmap handleSamplingAndRotationBitmap(Context context, Uri selectedImage)
        throws IOException {
    int MAX_HEIGHT = 1024;
    int MAX_WIDTH = 1024;

    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    InputStream imageStream = context.getContentResolver().openInputStream(selectedImage);
    BitmapFactory.decodeStream(imageStream, null, options);
    imageStream.close();

    // Calculate inSampleSize
    options.inSampleSize = calculateInSampleSize(options, MAX_WIDTH, MAX_HEIGHT);

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    imageStream = context.getContentResolver().openInputStream(selectedImage);
    Bitmap img = BitmapFactory.decodeStream(imageStream, null, options);

    img = rotateImageIfRequired(context, img, selectedImage);
    return img;
}

下面是前面提到的CalculateInSampleSize方法:

/**
  * Calculate an inSampleSize for use in a {@link BitmapFactory.Options} object when decoding
  * bitmaps using the decode* methods from {@link BitmapFactory}. This implementation calculates
  * the closest inSampleSize that will result in the final decoded bitmap having a width and
  * height equal to or larger than the requested width and height. This implementation does not
  * ensure a power of 2 is returned for inSampleSize which can be faster when decoding but
  * results in a larger bitmap which isn't as useful for caching purposes.
  *
  * @param options   An options object with out* params already populated (run through a decode*
  *                  method with inJustDecodeBounds==true
  * @param reqWidth  The requested width of the resulting bitmap
  * @param reqHeight The requested height of the resulting bitmap
  * @return The value to be used for inSampleSize
  */
private static int calculateInSampleSize(BitmapFactory.Options options,
                                         int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {

        // Calculate ratios of height and width to requested height and width
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will guarantee a final image
        // with both dimensions larger than or equal to the requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;

        // This offers some additional logic in case the image has a strange
        // aspect ratio. For example, a panorama may have a much larger
        // width than height. In these cases the total pixels might still
        // end up being too large to fit comfortably in memory, so we should
        // be more aggressive with sample down the image (=larger inSampleSize).

        final float totalPixels = width * height;

        // Anything more than 2x the requested pixels we'll sample down further
        final float totalReqPixelsCap = reqWidth * reqHeight * 2;

        while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap) {
            inSampleSize++;
        }
    }
    return inSampleSize;
}

然后是检查当前图像方向以确定旋转角度的方法

 /**
 * Rotate an image if required.
 *
 * @param img           The image bitmap
 * @param selectedImage Image URI
 * @return The resulted Bitmap after manipulation
 */
private static Bitmap rotateImageIfRequired(Context context, Bitmap img, Uri selectedImage) throws IOException {

InputStream input = context.getContentResolver().openInputStream(selectedImage);
ExifInterface ei;
if (Build.VERSION.SDK_INT > 23)
    ei = new ExifInterface(input);
else
    ei = new ExifInterface(selectedImage.getPath());
        
    int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);

    switch (orientation) {
        case ExifInterface.ORIENTATION_ROTATE_90:
            return rotateImage(img, 90);
        case ExifInterface.ORIENTATION_ROTATE_180:
            return rotateImage(img, 180);
        case ExifInterface.ORIENTATION_ROTATE_270:
            return rotateImage(img, 270);
        default:
            return img;
    }
}

最后是旋转方法本身

private static Bitmap rotateImage(Bitmap img, int degree) {
    Matrix matrix = new Matrix();
    matrix.postRotate(degree);
    Bitmap rotatedImg = Bitmap.createBitmap(img, 0, 0, img.getWidth(), img.getHeight(), matrix, true);
    img.recycle();
    return rotatedImg;
}

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。

我根据@Jason Robinson的回答创建了一个Kotlin扩展函数,简化了Kotlin开发人员的操作。我希望这能有所帮助。

fun Bitmap.fixRotation(uri: Uri): Bitmap? {

    val ei = ExifInterface(uri.path)

    val orientation: Int = ei.getAttributeInt(
        ExifInterface.TAG_ORIENTATION,
        ExifInterface.ORIENTATION_UNDEFINED
    )

    return when (orientation) {
        ExifInterface.ORIENTATION_ROTATE_90 -> rotateImage( 90f)
        ExifInterface.ORIENTATION_ROTATE_180 -> rotateImage( 180f)
        ExifInterface.ORIENTATION_ROTATE_270 -> rotateImage( 270f)
        ExifInterface.ORIENTATION_NORMAL -> this
        else -> this
    }
}

fun Bitmap.rotateImage(angle: Float): Bitmap? {
    val matrix = Matrix()
    matrix.postRotate(angle)
    return Bitmap.createBitmap(
        this, 0, 0, width, height,
        matrix, true
    )
}

通过使用滑动库,你可以得到图像与精确的方向,而不需要检查旋转

在kotlin

CoroutineScope(Dispatchers.IO).launch {
         var bitmap = Glide.with(context).asBitmap().load(imagePathOrUriOrLink)
                /*.apply(
                    RequestOptions()
                        .override(MAXIMUM_IMAGE_RESOLUTION)
                )*/ //uncomment it if you want original image
                /*.diskCacheStrategy(DiskCacheStrategy.NONE).skipMemoryCache(true)*/ //uncomment it you want to not cache image
                .submit().get()//this is synchronous approach  
}

使用这个依赖

api 'com.github.bumptech.glide:glide:4.12.0'
kapt 'com.github.bumptech.glide:compiler:4.12.0'