fade to black and white

fade to black and white

• michealdm

  No worries, glad to help.

  
  
  

• magicali

  The FotoVision sample has code in it to do greyscale using color matrices, to be honest, I knew that would work, but I've not really played with it.

   

  Having said that, it's img you want to save, not bmp. 

   

  
  
  

• Daniela Torres

  www.codeproject.com has my image processing articles. They show how to access the bits of an image directly, how to do a greyscale filter ( although it's quicker to do one using the color matrix, my approach is more generic ), and you could easily make a grey copy of an image, and animate the steps between the pixel values. I would not be surprised if XP builds a cache of images to do the animation in the moments before it starts, tho.

  
  
  

• LeBlah

  // bmp.Save("c:\")

  Replace this with an actual path and see what happens :-)

  
  
  

• Hassmann

  cgraus wrote:

  www.codeproject.com has my image processing articles.  They show how to access the bits of an image directly, how to do a greyscale filter ( although it's quicker to do one using the color matrix, my approach is more generic ), and you could easily make a grey copy of an image, and animate the steps between the pixel values.  I would not be surprised if XP builds a cache of images to do the animation in the moments before it starts, tho.

  ok, this is what i have, everything seems to be running ok, but the image does not save to c:\...am i missing something obvious

  Dim strpath1Image As Image = Image.FromFile(strPath1)

  grayscale(strpath1Image)

  End Sub

  Public Function grayscale(ByVal img As Image) As Boolean

  Dim cm As Imaging.ColorMatrix = New Imaging.ColorMatrix(New Single()() _

  {New Single() {0.299, 0.299, 0.299, 0, 0}, _

  New Single() {0.587, 0.587, 0.587, 0, 0}, _

  New Single() {0.114, 0.114, 0.114, 0, 0}, _

  New Single() {0, 0, 0, 1, 0}, _

  New Single() {0, 0, 0, 0, 1}})

   

  Return draw_adjusted_image(img, cm)

  End Function

  Private Function draw_adjusted_image(ByVal img As Image, _

  ByVal cm As Imaging.ColorMatrix) As Boolean

   

  Try

  Dim bmp As New Bitmap(img) ' create a copy of the source image

  Dim imgattr As New Imaging.ImageAttributes()

  Dim rc As New Rectangle(0, 0, img.Width, img.Height)

  Dim g As Graphics = Graphics.FromImage(img)

  ' associate the ColorMatrix object with an ImageAttributes object

  imgattr.SetColorMatrix(cm)

  ' draw the copy of the source image back over the original image,

  'applying the ColorMatrix

  g.DrawImage(bmp, rc, 0, 0, img.Width, img.Height, _

  GraphicsUnit.Pixel, imgattr)

  bmp.Save("c:\")

  g.Dispose()

  Return True

  Catch

  Return False

  End Try

  End Function

  
  

• Joshua Scholar

  works great, now I'm going to tweak the color settings to do a transitional fade...Thanks for your help
  

• DaveChapman

  cgraus wrote:

  // bmp.Save("c:\") Replace this with an actual path and see what happens :-)

   

  stupid me...so I added the rest of the path lol and it gives me an image, but it's not grey like it's supposed to be...

  
  
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