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• Convert BMP to JPG with this easy to use code. (Note: Requires vic32.dll available from http://www.

Convert BMP to JPG with this easy to use code. (Note: Requires vic32.dll available from http://www.

Convert BMP to JPG with this easy to use code. (Note: Requires vic32.dll available from https://www.catenary.com/)

API Declarations



Declare Function bmpinfo Lib "VIC32.DLL" (ByVal Fname As String, bdat As BITMAPINFOHEADER) As Long
Declare Function allocimage Lib "VIC32.DLL" (image As imgdes, ByVal wid As Long, ByVal leng As Long, ByVal BPPixel As Long) As Long
Declare Function loadbmp Lib "VIC32.DLL" (ByVal Fname As String, desimg As imgdes) As Long
Declare Sub freeimage Lib "VIC32.DLL" (image As imgdes)
Declare Function convert1bitto8bit Lib "VIC32.DLL" (srcimg As imgdes, desimg As imgdes) As Long
Declare Sub copyimgdes Lib "VIC32.DLL" (srcimg As imgdes, desimg As imgdes)
Declare Function savejpg Lib "VIC32.DLL" (ByVal Fname As String, srcimg As imgdes, ByVal quality As Long) As Long



' Image descriptor
Type imgdes
ibuff As Long
stx As Long
sty As Long
endx As Long
endy As Long
buffwidth As Long
palette As Long
colors As Long
imgtype As Long
bmh As Long
hBitmap As Long
End Type

Type BITMAPINFOHEADER
biSize As Long
biWidth As Long
biHeight As Long
biPlanes As Integer
biBitCount As Integer
biCompression As Long
biSizeImage As Long
biXPelsPerMeter As Long
biYPelsPerMeter As Long
biClrUsed As Long
biClrImportant As Long
End Type





Rate Convert BMP to JPG with this easy to use code. (Note: Requires vic32.dll available from http://www.

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Private Sub ConvertToJPEG(bmp_fname As String, jpg_fname As String, Optional quality As Long)
   Dim tmpimage As imgdes    ' Image descriptors
   Dim tmp2image As imgdes
   Dim rcode As Long
   'Dim quality As Long
   Dim vbitcount As Long
   Dim bdat As BITMAPINFOHEADER ' Reserve space for BMP struct
   'Dim bmp_fname As String
   'Dim jpg_fname As String

   'bmp_fname = "test.bmp"
   'jpg_fname = "test.jpg"

   If quality = 0 Then quality = 75
   
   ' Get info on the file we're to load
   rcode = bmpinfo(bmp_fname, bdat)
   If (rcode <> NO_ERROR) Then
      msgbox "error: Unable to get file info"
      Exit Sub
   End If
    
   vbitcount = bdat.biBitCount
   If (vbitcount >= 16) Then  ' 16-, 24-, or 32-bit image is loaded into 24-bit buffer
      vbitcount = 24
   End If
   
   ' Allocate space for an image
   rcode = allocimage(tmpimage, bdat.biWidth, bdat.biHeight, vbitcount)
   If (rcode <> NO_ERROR) Then
     msgbox "error: Not enough memory"
     Exit Sub
   End If
   
   ' Load image
   rcode = loadbmp(bmp_fname, tmpimage)
   If (rcode <> NO_ERROR) Then
      freeimage tmpimage ' Free image on error
      msgbox "error: Cannot load file"
      Exit Sub
   End If

   If (vbitcount = 1) Then ' If we loaded a 1-bit image, convert to 8-bit grayscale
       ' because jpeg only supports 8-bit grayscale or 24-bit color images
     rcode = allocimage(tmp2image, bdat.biWidth, bdat.biHeight, 8)
     If (rcode = NO_ERROR) Then
         rcode = convert1bitto8bit(tmpimage, tmp2image)
         freeimage tmpimage  ' Replace 1-bit image with grayscale image
         copyimgdes tmp2image, tmpimage
     End If
   End If

   ' Save image
   rcode = savejpg(jpg_fname, tmpimage, quality)
   freeimage tmpimage
   Kill bmp_fname
   msgbox "picture saved: " & jpg_fname
      
End Sub