IImage - Exporting portrait JPG photos on Android rotates them

[janseris]

Description

Every photo which is taken on portrait, is exported using Image.AsBytes() as landscape -> rotated counter-clockwise 90 degrees (rotate to the left).
Sample poject: MauiApp2 rotated portrait JPGs.zip

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Btw.: I am experiencing the same when exporting using Android.Graphics.Bitmap in Xamarin.

    byte[] XamarinResize(byte[] image, int width, int height)
    {
        var bitmap = Create(image);
        var matrix = new Android.Graphics.Matrix();
        var scaleWidth = ((float)width) / bitmap.Width;
        var scaleHeight = ((float)height) / bitmap.Height;
        matrix.PreScale(scaleWidth, scaleHeight);
        var resizedBitmap = Android.Graphics.Bitmap.CreateBitmap(bitmap, 0, 0, bitmap.Width, bitmap.Height, matrix, true); //size of original image must be entered
        byte[] exported = Export(resizedBitmap, 80);
        return exported;
    }

    //https://stackoverflow.com/questions/25976002/saving-bitmap-to-file-xamarin-monodroid
    byte[] Export(Android.Graphics.Bitmap bitmap, int jpgQuality)
    {
        using (var ms = new MemoryStream())
        {
            bitmap.Compress(Android.Graphics.Bitmap.CompressFormat.Jpeg, jpgQuality, ms);
            return ms.ToArray();
        }
    }

From this thread, it seems like the issue is that when a Bitmap is created, the Exif info is lost and it must be passed around to keep the original rotation.
https://stackoverflow.com/questions/66437183/xamarin-android-cant-read-exif-data-from-the-rotated-image-to-check-whether-the

Edit: Confirmed - all EXIF data is lost when exporting a JPG image using MAUI Graphics or Android.Graphics on Android. No property is preserved (datetime, device info, gps coordinates, rotation, ...). Everything is cut.

Test project for confirmation of this:

MauiApp2 EXIF properties disappearing demonstration.zip

---

Steps to Reproduce

export IImage as bytes

Version with bug

Release Candidate 2 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android, I was not able test on other platforms

Affected platform versions

Android 11 (API 30)

Did you find any workaround?

No because there is no API to detect image orientation/rotation or to rotate the image

Relevant log output

No response

[drasticactions]

Maui Graphics is its own repo: https://github.com/dotnet/Microsoft.Maui.Graphics

And I think your issue has to do with the platform itself, so https://github.com/xamarin/xamarin-android

@jonathanpeppers Is this something that could be addressed here or should it be moved to the other repos?

[jonathanpeppers]

I don't see how the above would be a problem in xamarin-android at all. If you call the Android APIs, and they give this result -- the same would happen in Java or Kotlin. Do you get the same result in an Android Studio project?

I don't think there is anything for us to fix here. You could file an issue on Maui.Graphics if one of their APIs is not working as expected.

[janseris]

@jonathanpeppers

Do you get the same result in an Android Studio project?

I have never used Android Studio or programmed a mobile app in Java or Kotlin.

I will transfer this to Maui.Graphics then.

[drasticactions]

@janseris His point is that this is something you can replicate with an Android app written in Java using the regular tooling. It's not a bug in the Xamarin.Android binding, nor is it something MAUI introduced. If you called those APIs from Java, you would (most likely) get the same result.