How to Convert a bitmap from grayscale to pure Black and White

[inotec]

I, can any one help me. I want to convert a image from grayscale to pure Black and White. Does anyone knows de matrix to convert fron graysclae to B&W or a way to do it.

Best Regards

INOTEC

 

[jperks1985]

Something I wrote up for my project, enjoy.

    Public Function BlackWhiteFilter(ByVal bp As Bitmap)


        Dim colorBlack As New Color
        Dim colorWhite As New Color
        Dim pixels As New ArrayList
        Dim x As Integer, y As Integer
        Dim size As New Size(200, 40)
        Dim imageSize As New Size(200, 40)
        Dim PixelX As Integer
        Dim PixelY As Integer

        colorBlack = Color.Black
        colorWhite = Color.White


        'Convert to black and white
        For x = PixelX - CInt(size.Width) To PixelX + CInt(size.Width)
            For y = PixelY - CInt(size.Height) To PixelY + CInt(size.Height)

                If (x > 0 And x < imageSize.Width) And (y > 0 And y < imageSize.Height) Then

                    Dim splitARGB As String()
                    Dim colR As String
                    splitARGB = Split(BP.GetPixel(x, y).ToString(), ",")
                    colR = Replace(splitARGB(1), " R=", "")

                    If colR < 200 Then
                        BP.SetPixel(x, y, colorBlack)
                    Else
                        BP.SetPixel(x, y, colorWhite)
                    End If

                End If
            Next
        Next

 

[inotec]

Thanks jperks1985.

The code is good, but it takes to much time to convert de image. I need something faster, like a ColorMatrix conversion. I want to convert a image frame from a webcam and convert it to B&W on the fly.

But thank you any way.
Best Regards
Inotec

 

[jperks1985]

Ah, if you find a solution please post it, I may be able to use it myself. Thanks

 

[Paszt]

ColorMatrix Basics - Simple Image Color Adjustment

 

[jperks1985]

Thank you sir.

 

[inotec]

Thanks, but it's for grayscale and negative, doesn’t have de colormatrix for Black and White.

Best Regards

Inotec