android - 如何在保存之前在 android 相机预览应用程序中旋转图像？

Question

我有一个以纵向模式拍照的 Android 相机应用程序，相机预览很好......但是当我拍照时它以横向模式保存......它旋转 90 度:我的代码 onPictureTaken():

PictureCallback jpegCallback = new PictureCallback() {
    @Override
    public void onPictureTaken(byte[] arg0, Camera arg1) {

        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
        String date = dateFormat.format(new Date());
        String photoFile = "Picture_" + date + ".jpg";

        String filename = pictureFileDir.getPath() + File.separator
                + photoFile;

        Log.e("path", filename.toString());

        File pictureFile = new File(filename);

        try {
            FileOutputStream fos = new FileOutputStream(pictureFile);
            fos.write(arg0);
            fos.close();

            Bitmap bm = BitmapFactory.decodeFile(filename);
            ByteArrayOutputStream bao = new ByteArrayOutputStream();
            bm.compress(Bitmap.CompressFormat.JPEG, 90, bao);
            byte[] ba = bao.toByteArray();
            // sba1 = Base64.encodeBytes(ba);
            int flag = 0; // you can pass the default 0 = Base64.DEFAULT
            String ba1 = Base64.encodeToString(ba, flag);

            // Log.e("base64", "-----" + ba1);

            Toast.makeText(AndroidCamera.this,
                    "New Image saved 22222:" + photoFile, Toast.LENGTH_LONG)
                    .show();
            Intent intent = new Intent(AndroidCamera.this,
                    UploadActivity.class);

            fileUri = Uri.fromFile(pictureFile);

            intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

            // start the image capture Intent
            startActivityForResult(intent,
                    CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
            launchUploadActivity(true);

        } catch (Exception error) {
            // Log.d(MakePhotoActivity.DEBUG_TAG, "File" + filename +
            // "not saved: "
            // + error.getMessage());
            Toast.makeText(AndroidCamera.this, "Image could not be saved.",
                    Toast.LENGTH_LONG).show();
        }
    }
};

Answer 1

您可以像这样将位图旋转 90 度:

Matrix matrix = new Matrix();
matrix.postRotate(90);
Bitmap rotatedBitmap = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);

在你的具体例子中，你需要将它保存回原来的路径:

Bitmap bm = BitmapFactory.decodeFile(filename);

Matrix matrix = new Matrix();
matrix.postRotate(90);    
Bitmap rotatedBitmap = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);

FileOutputStream fos = new FileOutputStream(pictureFile);
rotatedBitmap.compress(Bitmap.CompressFormat.JPEG, 90, fos);
fos.close();

您还可以使用 Camera.Parameters.setRotation()