iOS Question pictures is rotated withouth reason

Erel said:

Tip: better to be consistent with XUI.DefaultFolder (which is the same as File.DirDocuments).

What happens if you try to show the image before it is saved (Bitmap1)?

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Semen Matusovskiy said:

When you take a photo, a bitmap has a correct orientation. But bmp.WriteToStream does not write 'orientation' tag in Exif.
I found three parameters only : ColorSpace, PixelXDimension, PixelYDimension). Means IOS will assume UIImageOrientationUp.

Workaround ...

1) Add to the bottom

B4X:

#If OBJC
- (UIImage*) removeOrientation: (UIImage*) image { return [UIImage imageWithCGImage: [image CGImage] scale: [image scale] orientation: UIImageOrientationUp]; }
#End If

2) In PictureTaken after receiving a bitmap (let's name it bmp):
a) get image orientation

B4X:

    Dim byteOrientation As Byte = bmp.As(NativeObject).GetField("imageOrientation").AsNumber

b) set image orientation to UIImageOrientationUp (means The original pixel data matches the image's intended display orientation).

B4X:

    Dim no As NativeObject = Me
    bmp = no.RunMethod ("removeOrientation:", Array (bmp))

c) rotate a bitmap

B4X:

    Select Case byteOrientation
        Case 0
            ' bmp = bmp.Rotate (0)
        Case 1
            bmp = bmp.Rotate (180)
        Case 2
             bmp = bmp.Rotate (270)
        Case 3
            bmp = bmp.Rotate (90)
    End Select

After this you can use bmp.WriteToStream.

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