tiff里存的一个图片结束时会有一个偏移量。从那个偏移量再提取下一个图片。
TIFF to JPEG - the Visual Basic Source Code
Requires Victor Image Processing Library for 32-bit Windows v 5 or higher.
Private Sub mnuconvertTIFFtoJPG_Click()
Dim tmpimage As imgdes' Image descriptors
Dim tmp2image As imgdes
Dim rcode As Long
Dim quality As Long
Dim fileinfo As TiffData ' Reserve space for TIFF struct
Dim tif_fname As String
Dim jpg_fname As String
tif_fname = "test.tif"
jpg_fname = "test.jpg"
quality = 75
' Get info on the file we're to load
rcode = tiffinfo(tif_fname, fileinfo)
If (rcode <>NO_ERROR) Then
MsgBox "Cannot find file", 0, "Error encountered!"
Exit Sub
End If
' Allocate space for an image
rcode = allocimage(tmpimage, fileinfo.width, fileinfo.length, fileinfo.vbitcount)
If (rcode <>NO_ERROR) Then
MsgBox "Not enough memory", 0, "Error encountered!"
Exit Sub
End If
' Load image
rcode = loadtif(tif_fname, tmpimage)
If (rcode <>NO_ERROR) Then
freeimage tmpimage ' Free image on error
MsgBox "Cannot load file", 0, "Error encountered!"
Exit Sub
End If
If (fileinfo.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, fileinfo.width, fileinfo.length, 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
If (fileinfo.vbitcount = 16) Then ' If we loaded a 16-bit grayscale image, convert to 8-bit grayscale
' because jpeg only supports 8-bit grayscale
rcode = allocimage(tmp2image, filedat.width, filedat.length, 8)
If (rcode = NO_ERROR) Then
rcode = convertgray16to8(tmpimage, tmp2image)
freeimage tmpimage ' Replace 16-bit grayscale image with 8-bit grayscale image
copyimgdes tmp2image, tmpimage
End If
End If
' Save image
rcode = savejpg(jpg_fname, tmpimage, quality)
freeimage tmpimage
End Sub
........... Add these defines and declarations to your Global module ...........
' 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
' TIFF file info
Type TiffData
ByteOrder As Long
width As Long
length As Long
BitsPSample As Long
comp As Long
SamplesPPixel As Long
PhotoInt As Long
PlanarCfg As Long
vbitcount As Long
End Type
Declare Function tiffinfo Lib "VIC32.DLL" (ByVal Fname As String, tdat As TiffData) As Long
Declare Function loadtif Lib "VIC32.DLL" (ByVal Fname As String, desimg As imgdes) As Long
Declare Function convertgray16to8 Lib "VIC32.DLL" (srcimg As imgdes, resimg As imgdes) 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 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
1、首先需要点击主菜单栏里的“File”。2、其次可以发现有“ExportGraph”的子目录，点击之后选择“OpenDialop...”。
3、然后改成tiff（高保真），或者jpg格式，选择对文件名称“filename”进行更改，同时更改保存路径。
4、最后点击OK即可。
