I have placed a marker in
GoogleMap
Image
marker.icon = self.image(marker.icon, scaledToSize: CGSize(width: 3.0, height: 3.0))
To resize the image refer to :The simplest way to resize an UIImage?
Now the set the resized image as marker icon ,i.e,
marker.icon = self.imageWithImage(image: UIImage(named: "imageName")!, scaledToSize: CGSize(width: 3.0, height: 3.0))
Edit:
func imageWithImage(image:UIImage, scaledToSize newSize:CGSize) -> UIImage{
UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0);
image.drawInRect(CGRectMake(0, 0, newSize.width, newSize.height))
let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage
}