Victor Image Processing Library How-to Tips

Anima Giffy, a VB Sample Application to Create Animations

Anima Giffy is an application that demonstrates the Victor Library multiframe functions. With this app you can combine individual images into an animation. The screen above demonstrates loading an existing multiframe animation, controlling it with start and stop buttons, and displaying pixel values of an individual frame.

Images can be loaded from BMP, GIF, JPG, PNG, or TIF files. They can also be pasted from the clipboard. The sequence in which the images are loaded determines their sequence in the animation.

Frame conditions can be set for each frame:

    starting position
    transparent color

Global conditions can be set for the entire animation:

    background color
    number of times to loop through the animation
    animation size

VB Source Code

Download Anima Giffy application and source code. Requires the Victor Library v 5.52 commercial release or eval version.

Save frames to create an animated GIF - the Visual Basic Source Code

SaveAnimationFileAs is the most important function in Anima Giffy.

' From Anima Giffy 
' Save the animation file
Public Sub SaveAnimationFileAs(filename As String)
Dim rcode As Long
Dim tempimage As imgdes
Dim fileType As String
Dim savemode As Long
    On Error Resume Next
    Screen.MousePointer = 11  ' Display the hourglass mouse pointer.
    savemode = 8  ' uncompressed
   For j = 0 To numframes - 1
            ' This application has a global array of the frames. Each frame has an image descriptor.
            ' If the buffwidth of the image is not zero, the frame is open and it's a valid image and we will save it in the file
      If (framesarray(j).frameimgdes.buffwidth = 0) then
          GoTo nextj
      End If
      getbmhfromimage bmh, framesarray(j).frameimgdes
      If (bmh.biBitCount = 24) Then ' If we have a 24-bit image, convert to 8-bit palette color
            ' because gif only supports up to 8-bit pixel depth
          Dim colors As Long
          Dim reduction_mode As Long
          rcode = allocimage(tempimage, bmh.biWidth, bmh.biHeight, 8)
          If (rcode = NO_ERROR) Then
            rcode = standardpalette(tempimage)
            reduction_mode = CR_TSDDIFF   ' For the best image quality
            rcode = matchcolorimageex(framesarray(j).frameimgdes, tempimage, reduction_mode)
            If (rcode = NO_ERROR) Then
               rcode = savegifframe(filename, tempimage, gdata.savedata, fdataarray(j).savedata, savemode) ' Save 8-bit version of original image
            End If
            freeimage tempimage  ' Release 8-bit version of original image
          End If
            ' Save the image as is 
         rcode = savegifframe(filename, framesarray(j).frameimgdes, gdata.savedata, fdataarray(j).savedata, savemode) ' Save original image
      End If
      If (rcode <> NO_ERROR) Then
         GoTo done
      End If
   Next j
    Screen.MousePointer = 0   ' Reset the mouse pointer.
            ' Handle any errors
    If rcode <> NO_ERROR Then
        error_handler rcode, filename
    End If
End Sub

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