试试这段代码:
public static Bitmap ConvertTo24bpp(Image img) {
var bmp = new Bitmap(img.Width, img.Height, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (var gr = Graphics.FromImage(bmp))
gr.DrawImage(img, new Rectangle(0, 0, img.Width, img.Height));
return bmp;
}
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