resize image

[oneprofittips]

Good day. I couldn't figure out how to resize an image while maintaining the aspect ratio.
For example, I have an image with dimensions 333 x 70.
I need to resize the image to 640 x 640 while preserving the aspect ratio, center it, and fill the background areas (where the image doesn't fit) with green color.

[ojb500]

Here's how I would do it

• Load your 333x70 source image into a SKImage
• Create a new SKSurface of 640x640 size
• Clear the new canvas to green canvas.Clear(SKColors.Green)
• Solve for the scaling factor you need, in this case it's going to be var scale = 640f/333f (this calculation needs to be able to deal with images that are taller than they are wide, bigger than the destination, etc)
• Work out the pixel size of the source image after resizing - newWidth = 333f * scale, newHeight = 70f * scale
• Work out the rectangle we need to draw the source image into
  var targetRect = new SKRect(640f/2 - newWidth/2, 640f/2 - newHeight/2, newWidth, newHeight) (might need some rounding here)
• Draw the image into the destination rectangle: canvas.DrawImage(source, targetRect)