public static void ScaleImage(Bitmap image, FixedDimension? fixedDimension, int maxDimension, Stream saveTo)
{
Size imageSize = CalculateSize(image.Size, fixedDimension, maxDimension);
Bitmap thumbnailImage = new Bitmap(imageSize.Width, imageSize.Height);
Graphics graphics = Graphics.FromImage(thumbnailImage);
graphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
graphics.DrawImage(image, 0, 0, thumbnailImage.Width, thumbnailImage.Height);
thumbnailImage.Save(saveTo, System.Drawing.Imaging.ImageFormat.Jpeg);
saveTo.Position = 0;
}
private static Size CalculateSize(Size image, FixedDimension? fixedDimension, int maxDimension)
{
int width;
int height;
if ((fixedDimension.HasValue && fixedDimension.Value == FixedDimension.Width) || (image.Width > image.Height))
{
width = maxDimension;
height = (maxDimension * image.Height) / image.Width;
}
else if ((fixedDimension.HasValue && fixedDimension.Value == FixedDimension.Height) || (image.Height > image.Width))
{
height = maxDimension;
width = (maxDimension * image.Width) / image.Height;
}
else
width = height = maxDimension;
return new Size(width, height);
}
