Xamarin.Android Rotate and Resize

resize.cs

public static System.IO.Stream ResizeAndRotate(string filePath, int maxWidth, int maxHeight, float jpegQuality)
{
	// loads just the dimensions of the file instead of the entire image
	var options = new BitmapFactory.Options { InJustDecodeBounds = true };
	BitmapFactory.DecodeFile (filePath, options);

	int outHeight = options.OutHeight;
	int outWidth = options.OutWidth;
	int inSampleSize = 1;

	if (outHeight > maxHeight || outWidth > maxWidth)
	{
		inSampleSize = (outWidth > outHeight) ? outWidth / maxWidth : outHeight / maxHeight;
	}
		
	options.InSampleSize = inSampleSize;
	options.InJustDecodeBounds = false;

	// decodes image file
	var newBitmap = BitmapFactory.DecodeFile (filePath, options);
	var matrix = new Matrix ();

	// rotates the image if needed.
	// Known Issue: HTC phones will report all pictures as landscape orientation.
	ExifInterface exif = new ExifInterface (filePath);
	var orientation = (Orientation)exif.GetAttributeInt (ExifInterface.TagOrientation, (int)Orientation.Undefined);
	switch(orientation)
	{
		case Orientation.Normal:
			// landscape. Don't do anything
			break;
		case Orientation.Rotate180:
			matrix.PreRotate (180);
			break;
		case Orientation.Rotate270:
			matrix.PreRotate (270);
			break;
		default:
			// handles portrait and other orientations that we may not need to handle.
			matrix.PreRotate (90);
			break;
	}

	newBitmap = Bitmap.CreateBitmap(newBitmap, 0, 0, newBitmap.Width, newBitmap.Height, matrix, false);
	matrix.Dispose();
	matrix = null;

	byte[] newImageData;
	int quality = (int)(jpegQuality * 100);
	using (var stream = new System.IO.MemoryStream())
	{
		newBitmap.Compress(Bitmap.CompressFormat.Jpeg, quality, stream);
		newBitmap.Recycle ();
		newBitmap.Dispose ();
		newBitmap = null;
		return stream;
	}
}