asp.net - 使用 DrawString-Method (ASP.NET) 渲染图像的效果很丑陋

Question

我想在 ASP.NET 中将一些文本呈现为图像。它运行良好，但即使我通过更改图形 TextRenderingHint 选项打开 AntiAlias(或 ClearType)，文本也会呈现非常难看(文本周围有灰色像素)。

相关代码如下:

    float width;
    float height;

    System.Drawing.Text.PrivateFontCollection fontcollection = new System.Drawing.Text.PrivateFontCollection();
    // Add the custom font families
    fontcollection.AddFontFile(Server.MapPath("./Fonts/" + fontfile));


    Bitmap image = new Bitmap(10, 10);
    Graphics graphic = Graphics.FromImage(image);
    Font font = new Font(fontcollection.Families.First(), fontsize, style);

    SizeF size = graphic.MeasureString(text, font);
    width = size.Width;
    height = size.Height;

    image = new Bitmap(Convert.ToInt32(width), Convert.ToInt32(height));
    graphic = Graphics.FromImage(image);
    graphic.FillRectangle(new SolidBrush(Color.White), 0, 0, width, height);

    graphic.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
    graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.Bicubic;
    graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
    graphic.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;

    graphic.DrawString(text, font, Brushes.Black, new PointF(0, 0));

    Response.ContentType = "image/jpeg";
    image.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);

这里是生成图像的链接(缩放):

未缩放的图像:

我该如何解决这个问题？

Answer 1

将图像格式设置为 PNG。

默认的 JPEG 压缩没有用。