compression while converting tiffs to pdf

[charuvas1]

Hi,

I am trying to convert multiple single page tiffs to one multi page pdf file. The tiffs are scanned and I have to maintain the dpi of the tiff images while converting them to pdf. Is there a way of doing so? Which compression is used for images while converting to pdf? Following is the code-

Code: Select all

Dim dr As New System.IO.DirectoryInfo(System.IO.Path.GetTempPath & "Scanner_sample")
            Dim fl As System.IO.FileInfo() = dr.GetFiles()
            Dim imgcnt As Integer
            Dim pdfid As Integer = oGdPictureImaging.PdfNewPdf(System.IO.Path.GetTempPath & "Scanner_sample\Multipg_pdf.pdf", "charu", "charu", "charu", "charu", "charu")
            For Each fl1 As System.IO.FileInfo In fl
                oGdPictureImaging.TiffOpenMultiPageForWrite(True)
                Dim m_img As Integer = oGdPictureImaging.CreateGdPictureImageFromFile(fl1.FullName)
                If m_img <> 0 Then
                     imgcnt = oGdPictureImaging.PdfAddImageFromGdPictureImage(pdfid, m_img) 
                end if
                    oGdPictureImaging.ReleaseGdPictureImage(m_img)
             next
      For i As Integer = 1 To imgcnt
                oGdPictureImaging.PdfNewPage(pdfid, oGdPictureImaging.PdfGetImageWidth(pdfid, i), oGdPictureImaging.PdfGetImageHeight(pdfid, i))
                Call oGdPictureImaging.PdfDrawImage(pdfid, i, 0, 0, oGdPictureImaging.PdfGetImageWidth(pdfid, i), oGdPictureImaging.PdfGetImageHeight(pdfid, i))
            Next
            oGdPictureImaging.PdfEndPdf(pdfid)

Your quick response would be highly appreciated.

Thanks
Charu

[Loïc]

Hi,

Code: Select all

The tiffs are scanned and I have to maintain the dpi of the tiff images while converting them to pdf. Is there a way of doing so? 

This is done automatically when you add a GdPicture image to a PDF.

Code: Select all

Which compression is used for images while converting to pdf? 

CCITT4 for bitonal images, JPEG for color an 8bit grayscale image, else Flate compression.

Kind regards,

Loïc