Vb.net图像蒙版沿着边缘平滑

Question

嘿所有我试图通过使用蒙版来使我的图像看起来漂亮和平滑（抗锯齿），以便制作圆形图像，如下所示：

原始图像如下所示：

上图中的蒙版看起来像这样（红色是要取出的蒙版颜色）：

它可以工作，但它给了我周围不那么漂亮的锯齿状边缘。掩码是.png，图像本身也是.png。

我用来制作面具的代码是：

picNextTopic1.Image = Image.FromStream(wc.OpenRead(anAPI.wallOrgPostImage(keying).Replace("{width}", "50").Replace("{height}", "50"))) 'Download the image from the website.                  
picNextTopic1.Image = ApplyMask(New Bitmap(picNextTopic1.Image), New Bitmap(My.Resources.mask), Color.Red) 'Apply mask to the downloaded image above.

ApplyMask函数是这样的：

Public Function ApplyMask(ByVal bImg As Bitmap, ByVal bMask As Bitmap, ByVal maskColor As Color) As Image
    Dim wImg As Integer = bImg.Width
    Dim hImg As Integer = bImg.Height
    Dim wMask As Integer = bMask.Width
    Dim hMask As Integer = bMask.Height
    Dim intMask As Integer = maskColor.ToArgb
    Dim intTransparent As Integer = Color.Transparent.ToArgb

    Using fpImg As New FastPix(bImg)
        Using fpMask As New FastPix(bMask)
            Dim pixelsImg = fpImg.PixelArray
            Dim pixelsMask = fpMask.PixelArray

            For y As Integer = 0 To Math.Min(hImg, hMask) - 1
                For x As Integer = 0 To Math.Min(wImg, wMask) - 1
                    Dim iImg As Integer = (y * wImg) + x
                    Dim iMask As Integer = (y * wMask) + x

                    If pixelsMask(iMask) = intMask Then
                        pixelsImg(iImg) = intTransparent
                    End If
                Next
            Next
        End Using
    End Using

    Return bImg
End Function

使用 FastPix 找到here。

任何有助于解决这个问题的帮助都会很棒！谢谢！

更新 我有透明表格的代码：

Public Sub InitializeMyForm()
    BackColor = Color.Plum
    TransparencyKey = BackColor
End Sub

Answer 1

玩弄这个，我确实设法使用TextureBrush以这种方式制作一个平滑的图像：

Dim profile As Image = Image.FromFile("c:\...\profile.png")

Protected Overrides Sub OnPaint(e As PaintEventArgs)
  e.Graphics.Clear(Color.SteelBlue)
  e.Graphics.SmoothingMode = SmoothingMode.AntiAlias
  Using tb As New TextureBrush(profile)
    tb.TranslateTransform(120, 64)
    Using p As New GraphicsPath
      p.AddEllipse(120, 64, profile.Width, profile.Width)
      e.Graphics.FillPath(tb, p)
    End Using
  End Using
  MyBase.OnPaint(e)
End Sub

TranslateTransform和AddEllipse位置使用相同的点信息，以便适当地“居中”纹理画笔。

结果：