Is there any way to change a pictures brightness through code (aka fade the
picture) without using a custom control?

-Dan

Here's one way to do a fade.  It uses GetDIBits() to get a copy of the
picture in memory where you can manipulate the palette and SetDIBits() to
blast the result back to the screen: it's pretty fast for reasonable-size
bitmaps (not sure about fullscreen!).  This routine is intrinsically
16-color, but you could alter it to 256-color (roughly half as fast) or
24-bit color (_way_ slower).  Anyway, it may give you a starting point.

Note that it does not _realize_ the palette, so if you want it to run in
256-color video (forget it in 16-color) you'll have to realize an
appropriate palette yourself.

It's got a slightly clever method of making the fade speed somewhat
independent of the machine speed by doing the fade in four parts, timing
each one, and adjusting on the fly.

Jim Deutch
MS Dev MVP

Private Type BITMAPINFOHEADER   '40 bytes
   biSize As Long
   biWidth As Long
   biHeight As Long
   biPlanes As Integer
   biBitCount As Integer
   biCompression As Long
   biSizeImage As Long
   biXPel{*filter*}eter As Long
   biYPel{*filter*}eter As Long
   biClrUsed As Long
   biClrImportant As Long
End Type

Private Type RGBQUAD
   rgbBlue As Byte
   rgbGreen As Byte
   rgbRed As Byte
   rgbReserved As Byte
End Type

Private Type BITMAPINFO_4
   bmiHeader As BITMAPINFOHEADER
   bmiColors(15) As RGBQUAD
End Type

Private Const PIXEL As Integer = 3
Private Const DIB_RGB_COLORS As Long = 0

Private Declare Function GetDIBits4 Lib "gdi32" Alias "GetDIBits" _
  (ByVal aHDC As Long, ByVal hBitmap As Long, ByVal nStartScan As Long, _
  ByVal nNumScans As Long, lpBits As Any, lpBI As BITMAPINFO_4, _
  ByVal wUsage As Long) As Long

Private Declare Function SetDIBits4 Lib "gdi32" Alias "SetDIBits" (ByVal
hdc As Long, _
  ByVal hBitmap As Long, ByVal nStartScan As Long, _
  ByVal nNumScans As Long, lpBits As Any, lpBI As BITMAPINFO_4, _
  ByVal wUsage As Long) As Long

Private Declare Function BitBlt& Lib "gdi32" (ByVal hDestDC As Long, _
  ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As
Long, _
  ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal dwRop
As Long)

    Static SaveBits() As Byte
    Static SaveBitmapInfo_4 As BITMAPINFO_4
    Static nLen As Long
    Static Start As Single
    Static SubIters As Long
    Static nName As Long
    Static y As Long
    Dim BufferSize As Long
    Dim retval As Long
    Dim i As Long
    Dim cFace As Long
    Dim R As Long, G As Long, B As Long
    Static x As Long
    Static j As Single
    Dim Level As Long
    Static picSrcDC As Long
    Static frmDC As Long
    Static picSrcLeft As Long
    Static picSrcTop As Long
    Static picSrcWidth As Long
    Static picSrcHeight As Long

        'realize the palette
        picpal.ZOrder
        'size a buffer for the pixel data
        BufferSize = ((picSrc.ScaleWidth / 2 + 3) And &HFFFC) *
picSrc.ScaleHeight
        ReDim SaveBits(0 To BufferSize - 1)  'As Byte
        'fill the header info for the save copy
        With SaveBitmapInfo_4.bmiHeader
            .biSize = 40
            .biWidth = picSrc.ScaleWidth
            .biHeight = picSrc.ScaleHeight
            .biPlanes = 1
            .biBitCount = 4
            .biCompression = 0
            .biClrUsed = 0
            .biClrImportant = 0
            .biSizeImage = BufferSize
        End With
        nLen = Len(SaveBitmapInfo_4)
        'get the bitmap from the picturebox
        retval = GetDIBits4(picSrc.hdc, picSrc.Image, 0, _
            SaveBitmapInfo_4.bmiHeader.biHeight, SaveBits(0),
SaveBitmapInfo_4, DIB_RGB_COLORS)

        'cache stuff
        picSrcDC = picSrc.hdc
        frmDC = Me.hdc
        picSrcLeft = picSrc.Left ' / Screen.TwipsPerPixelX
        picSrcTop = picSrc.Top ' / Screen.TwipsPerPixelY
        picSrcWidth = picSrc.ScaleWidth
        picSrcHeight = picSrc.ScaleHeight

        'fade in the logo

        For i = 0 To 4
            Start = Timer
            'change the palette
            j = 0
            Do
                j = j + Incr
                Level = i * 51 + j
                If Level > 255 Then Exit Do
                SaveBitmapInfo_4.bmiColors(4).rgbBlue = Level / 2
                SaveBitmapInfo_4.bmiColors(15).rgbBlue = Level
                SaveBitmapInfo_4.bmiColors(15).rgbRed = Level
                SaveBitmapInfo_4.bmiColors(15).rgbGreen = Level
                'blast it back into the picturebox
                retval = SetDIBits4(picSrcDC, picSrc.Image.handle, 0, _
                    SaveBitmapInfo_4.bmiHeader.biHeight, SaveBits(0),
SaveBitmapInfo_4, DIB_RGB_COLORS)
                'transfer it to the form
                retval = BitBlt(frmDC, picSrcLeft, picSrcTop, _
                  picSrcWidth, picSrcHeight, picSrcDC, 0, 0, SRCCOPY)
            Loop While j < 52
            If Timer - Start = 0 Then
                Incr = Incr / 2
            Else
                Incr = Incr / (SECONDS_FADE_LOGO / 5 / (Timer - Start))
            End If
        Next i