How to convert TIF to JPG using VBA ExportRasterFile?

RE: How to convert TIF to JPG using VBA ExportRasterFile?

hirotaka nisimura — Mon, 17 Jan 2022 01:49:23 GMT

I read MicrostationVBA.chm and tried some ways, then I could save JPEG from TIFF using ExportRasterfile. The string 'JPEG(J)' is not wrong but I have to add some arguments to my code.

RasterManager.ExportRasterFile sourcefilename:=fname, _
destinationfilename:=outname, _
NewFormatSpecifier:=oRF, _
NewColorModeSpecifier:=oColor, _
NewCompressionModeSpecifier:=oCOMPRESS

I got RasterFormat from another JPEG raster. And I got ColorMode and CompressionMode from it, then I set them as the arguments for ExortRasterFile.

Then I excuted my improved code, it made JPEG from TIFF.

RE: How to convert TIF to JPG using VBA ExportRasterFile?

hirotaka nisimura — Mon, 17 Jan 2022 01:20:57 GMT

Thank you Jon. I checked the filename. In the case that I set 'JPEG' for Raster, the new file was saved. But it was TIFF, not JPEG format.

And I chekced RasterFormats class using your code. As the result, The string of RasterFormat for JPEG is 'JPEG(J)' so I tried again. But it don't work.

RE: How to convert TIF to JPG using VBA ExportRasterFile?

Jon Summers — Fri, 14 Jan 2022 14:30:58 GMT

[quote userid="923155" url="~/products/programming/microstation_programming/f/microstation-programming---forum/224579/how-to-convert-tif-to-jpg-using-vba-exportrasterfile"]I get run time error 5[/quote]

Add some Debug statements to help find the problem.

Const Backslash As String = "\"

Dim source As String
source = fpath & Backslash & fName
Debug.Print "Source=" & source

Dim raster As String
raster = fpath & Backslash & fso.GetBaseName(fname) & ".jpg"
Debug.Print "Raster=" & raster

The Debug.Print statement prints to the VBA Immediate window. Are those valid file names?

The RasterFormats class is not well-documented. It's not clear whether JPEG(J) is a valid search criterion. The sole example I can find is...

 Set oFormat = RasterManager.RasterFormats.Find("TI~FF")

This always fails...

Sub TestRaster()
    Dim rm As RasterManager
    Set rm = RasterManager
    Dim oFormat As raster
    Dim formatName As String
    formatName = "JPEG(J)"
    Set oFormat = rm.RasterFormats.Find(formatName)
    If oFormat Is Nothing Then
        Debug.Print "Invalid format name " & formatName
    Else
        Debug.Print "Format name " & formatName & " is valid"
    End If
End Sub

However, "JPEG" is valid.

Here's how to list all raster formats...

Sub TraceRasterFormats()
    Dim oFormat As RasterFormat
    Dim oFormats As RasterFormats
    Dim nFormat As Long
    nFormat = 1
    Dim msg     As String
    Set oFormats = RasterManager.RasterFormats
    For Each oFormat In oFormats
        msg = "Raster Format [" & CStr(nFormat) & "] = '" & oFormat.ToString() & "'"
        ShowMessage msg, msg, msdMessageCenterPriorityDebug
        Debug.Print msg
        nFormat = 1 + nFormat
    Next
End Sub