DrawCCITT with TIFF RAW data

1. offizieller Beitrag

    Hi,

    I am using TIFFReadRawStrip from LibTIFF to read raw data from a TIFF image and store it into a buffer. So, the pure data is read. None of the TIFF tags, only image data in COMPRESSION_CCITTFAX4 format.

    The problem is that I'm trying to use DrawCCITT method from wPDF and it is not working. The raw data are written in the PDF but when I try to open it, an error message appears saying that there are problems with the PDF and the image is not showed.

    Here is part of code:

    //_rInfoTIFF.Image is a PChar buffer.
    // pageWidth = imageWidth; pageHeight = imageHeight

    _rPDFPrinter.DrawCCITT(0, 0, pageWidth, pageHeigth , imageWidth, imageHeigth, wpCCITT_42D, _rInfoTIFF.Image, _rInfoTIFF.BufSize);

    The buffer is correctly filled. Databuffer is written into pdf file.
    Am I doing something wrong?

    This is your header in PDF file

    If I change it to this one

    Everything works like a charm!

    So, my question is, why DrawCCITT is not working correctly?

    Zitat von wpsupport

    The build posted on 14.6.2011 includes the changed code which writes correct PDF code.

    I'm sorry to say that but it is not working yet.

    I got PDF Error (15) when I try to load it in acrobat reader.

    This is your code:

    Code
    3 0 obj<</Type/XObject/Subtype/Image/Name/wpt1/Width 1664/Height 2398/BitsPerComponent 1 /ColorSpace/DeviceGray /DecodeParms <</BlackIs1 false /EndOfLine false /EndOfBlock false /K 1 /Columns 1664 /Rows 2398>> /Length 27194/Filter [/CCITTFaxDecode] >>stream


    It should be:

    Code
    3 0 obj
<<
/Type/XObject/Subtype/Image
/Name/wpt1
/Width 1664
/Height 2398
/BitsPerComponent 1 /ColorSpace/DeviceGray /DecodeParms <</BlackIs1 false /EndOfLine false /EndOfBlock false 
/K -1 /Columns 1664 /Rows 2398>> /Length 27194
/Filter /CCITTFaxDecode >>
stream

    I changed /K parameter (with a minus signal) and removed the brackets in /Filter. With this changes, it works.

    Did you guys test it?