Transforming Rectangle Coordinates to a Large Resolution Image

[rainbowerxtreme]

I'm using the following code to Transform a small rectangle coordinates to a larger one ie: A rectangle position on a small image to the same position on the larger resolution of the same image


Rectangle ConvertToLargeRect(Rectangle smallRect, Size largeImageSize, Size smallImageSize)
{
double xScale = (double)largeImageSize.Width / smallImageSize.Width;
double yScale = (double)largeImageSize.Height / smallImageSize.Height;
int x = (int)(smallRect.X * xScale + 0.5);
int y = (int)(smallRect.Y * yScale + 0.5);
int right = (int)(smallRect.Right * xScale + 0.5);
int bottom = (int)(smallRect.Bottom * yScale + 0.5);
return new Rectangle(x, y, right - x, bottom - y);
}

But there seems to be a problem with some images.The transformed rectangle coordinates seems to be off the image.

***UPDATE:***



img.Draw(rect, new Bgr(232, 3, 3), 2);
Rectangle transret= ConvertToLargeRect(rect, orgbitmap.Size, bit.Size);
target = new Bitmap(transret.Width, transret.Height);
using (Graphics g = Graphics.FromImage(target))
{
g.SmoothingMode = SmoothingMode.HighQuality;
g.DrawImage(orgbitmap, new Rectangle(0, 0, target.Width, target.Height),
transret, GraphicsUnit.Pixel);
}
Rectangle Drawn on small resolution Image

{X=190,Y=2,Width=226,Height=286}



Rectangle Transformed into Orginal Large Resolution Image `{X=698,Y=7,Width=830,Height=931}`

Original Image



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