为什么从 Android 相机拍摄的图像 bitmap 被旋转

Question

我正在使用 IMAGE_CAPTURE 相机意图来捕捉和成像，并使用 MediaStore.EXTRA_OUTPUT 将其存储在文件中。 当我在 onActivityResult 中收到图像时，旋转 bitmap。

请就如何解决此问题提出任何建议。

意图并将 uri 传递到我想要存储文件的位置

private fun capturePhoto() {
    val capturedImage = File(this.requireContext().externalCacheDir, "utility_bill.jpg")
    if (capturedImage.exists()) {
        capturedImage.delete()
    }
    capturedImage.createNewFile()
    mUri = if (Build.VERSION.SDK_INT >= 24) {
        FileProvider.getUriForFile(
            this.requireContext(),
            this.requireContext().applicationContext.packageName,
            capturedImage
        )
    } else {
        Uri.fromFile(capturedImage)
    }

    val intent = Intent("android.media.action.IMAGE_CAPTURE")
    intent.putExtra(MediaStore.EXTRA_OUTPUT, mUri)
    startActivityForResult(intent, CAMERA_REQUEST_CODE)
}

在 onActivityResult bitmap 中旋转。

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        hideScreen.visibility = View.GONE
        if (resultCode == Activity.RESULT_OK && requestCode == CAMERA_REQUEST_CODE) {
            uploadedImageCount++
            val bitmap = BitmapFactory.decodeStream(
                this.requireContext().contentResolver.openInputStream(mUri!!)
            )
}}

我拍摄的图像

当我调试代码中收到的 bitmap 时，它被旋转了

请就我如何解决这个问题提出任何建议

提前致谢 R

Answer 1

我在开发应用程序时遇到了同样的问题，三星、HTC 和某些设备等设备就是这种情况....这是因为 Exif 接口与上面提到的设备不同所以单独制作一个 Java class ExifUtil .java代码如下所示注意此代码位于 Java

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.os.Build;

public class ExifUtil {
    /**
//     * @see https://sylvana.net/jpegcrop/exif_orientation.html
     */
    public static Bitmap rotateBitmap(String src, Bitmap bitmap) {
        try {
            int orientation = getExifOrientation(src);

            if (orientation == 1) {
                return bitmap;
            }

            Matrix matrix = new Matrix();
            switch (orientation) {
                case 2:
                    matrix.setScale(-1, 1);
                    break;
                case 3:
                    matrix.setRotate(180);
                    break;
                case 4:
                    matrix.setRotate(180);
                    matrix.postScale(-1, 1);
                    break;
                case 5:
                    matrix.setRotate(90);
                    matrix.postScale(-1, 1);
                    break;
                case 6:
                    matrix.setRotate(90);
                    break;
                case 7:
                    matrix.setRotate(-90);
                    matrix.postScale(-1, 1);
                    break;
                case 8:
                    matrix.setRotate(-90);
                    break;
                default:
                    return bitmap;
            }

            try {
                Bitmap oriented = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
                bitmap.recycle();
                return oriented;
            } catch (OutOfMemoryError e) {
                e.printStackTrace();
                return bitmap;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        return bitmap;
    }

    private static int getExifOrientation(String src) throws IOException {
        int orientation = 1;

        try {
            /**
             * if your are targeting only api level >= 5
             * ExifInterface exif = new ExifInterface(src);
             * orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, 1);
             */
            if (Build.VERSION.SDK_INT >= 5) {
                Class<?> exifClass = Class.forName("android.media.ExifInterface");
                Constructor<?> exifConstructor = exifClass.getConstructor(new Class[] { String.class });
                Object exifInstance = exifConstructor.newInstance(new Object[] { src });
                Method getAttributeInt = exifClass.getMethod("getAttributeInt", new Class[] { String.class, int.class });
                Field tagOrientationField = exifClass.getField("TAG_ORIENTATION");
                String tagOrientation = (String) tagOrientationField.get(null);
                orientation = (Integer) getAttributeInt.invoke(exifInstance, new Object[] { tagOrientation, 1});
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }

        return orientation;
    }
}

和 OnActivityResult 像这样保存它 Bitmap orientedBitmap = ExifUtil.rotateBitmap(img_path, myBitmap);

this will automatically determine the orientation of the mage and rotate it to Potrait...!!