Пример #1
0
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // read document structure tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                Console.WriteLine("No Tags available");
            }
            else
            {
                for (var i = 0; i < struct_tree.GetNumKids(); i++)
                {
                    PdsObject        kid_object  = struct_tree.GetKidObject(i);
                    PdsStructElement struct_elem = struct_tree.AcquireStructElement(kid_object);
                    ProcessStructElement(doc, struct_elem, "");
                    struct_elem.Release();
                }
            }


            doc.Close();
            pdfix.Destroy();
        }
        public static void Run(
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // tag text on the bottom of the page as artifact
            for (int i = 0; i < struct_tree.GetNumChildren(); i++)
            {
                PdsObject        kid_obj  = struct_tree.GetChildObject(i);
                PdsStructElement kid_elem = struct_tree.GetStructElementFromObject(kid_obj);
                RemoveParagraph(kid_elem);
            }

            // the struct tree was updates, save page content on each page to apply changes
            for (int i = 0; i < doc.GetNumPages(); i++)
            {
                PdfPage page = doc.AcquirePage(i);
                MarkUntaggedObjectsAsArtifact(page);
                page.Release();
            }

            if (!doc.Save(savePath, Pdfix.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
        }
        //////////////////////////////////////////////////////////////////////////////////////////////////
        // Remove paragraph from structure tree
        // re-tag the struct element to heading based on font properties
        //////////////////////////////////////////////////////////////////////////////////////////////////
        internal static void RemoveParagraph(PdsStructElement struct_elem)
        {
            // remove last 2 P struct elements from struct tree
            for (int i = struct_elem.GetNumKids() - 1; i >= 0; i--)
            {
                if (struct_elem.GetKidType(i) == PdfStructElementType.kPdsStructKidElement)
                {
                    PdsObject        kid_obj  = struct_elem.GetKidObject(i);
                    PdsStructElement kid_elem = struct_elem.GetStructTree().AcquireStructElement(kid_obj);

                    string type = kid_elem.GetType_(true);
                    if (type == "P")
                    {
                        for (int j = kid_elem.GetNumKids() - 1; j >= 0; j--)
                        {
                            if (!kid_elem.RemoveKid(j))
                            {
                                throw new Exception(pdfix.GetErrorType().ToString());
                            }
                        }
                    }
                    else if (type == "Figure")
                    {
                        // remove figure if does not contain an alt text
                        string alt = kid_elem.GetAlt();
                        if (alt.Length == 0)
                        {
                            for (int j = kid_elem.GetNumKids() - 1; j >= 0; j--)
                            {
                                if (!kid_elem.RemoveKid(j))
                                {
                                    throw new Exception(pdfix.GetErrorType().ToString());
                                }
                            }
                        }
                    }
                    else
                    {
                        RemoveParagraph(kid_elem);
                    }
                    // remove this element if it has no kids
                    if (kid_elem.GetNumKids() == 0)
                    {
                        struct_elem.RemoveKid(i);
                    }

                    kid_elem.Release();
                }
                // remove only 2 paragraphs in this sample
                if (++count >= 2)
                {
                    break;
                }
            }
        }
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }


            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement figure = GetFirstFigure(struct_tree);

            if (figure == null)
            {
                throw new Exception("No figure found.");
            }

            if (!figure.SetAlt("This is a new alternate text"))
            {
                throw new Exception(pdfix.GetError());
            }

            if (!doc.Save(savePath, PdfSaveFlags.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
            pdfix.Destroy();
        }
        //////////////////////////////////////////////////////////////////////////////////////////////////
        // GetFirstParagraph
        // get reference to the first paragraph on the page
        //////////////////////////////////////////////////////////////////////////////////////////////////
        private static PdsStructElement GetFirstTable(PdsStructElement struct_elem)
        {
            // search kid struct elements
            for (int i = 0; i < struct_elem.GetNumChildren(); i++)
            {
                if (struct_elem.GetChildType(i) == PdfStructElementType.kPdsStructChildElement)
                {
                    PdsObject        kid_obj  = struct_elem.GetChildObject(i);
                    PdsStructElement kid_elem = struct_elem.GetStructTree().GetStructElementFromObject(kid_obj);
                    if (kid_elem == null)
                    {
                        throw new Exception(pdfix.GetErrorType().ToString());
                    }

                    string type = kid_elem.GetType_(true);
                    if (type == "Table")
                    {
                        return(kid_elem);
                    }

                    var table = GetFirstTable(kid_elem);
                    if (table != null)
                    {
                        return(table);
                    }
                }
            }
            return(null);
        }
        //////////////////////////////////////////////////////////////////////////////////////////////////
        // GetFirstParagraph
        // get reference to the first paragraph on the page
        //////////////////////////////////////////////////////////////////////////////////////////////////
        private static PdsStructElement GetFirstParagraph(PdsStructElement struct_elem)
        {
            // search kid struct elements
            for (int i = 0; i < struct_elem.GetNumKids(); i++)
            {
                if (struct_elem.GetKidType(i) == PdfStructElementType.kPdsStructKidElement)
                {
                    PdsObject        kid_obj  = struct_elem.GetKidObject(i);
                    PdsStructElement kid_elem = struct_elem.GetStructTree().AcquireStructElement(kid_obj);
                    if (kid_elem == null)
                    {
                        throw new Exception(pdfix.GetErrorType().ToString());
                    }

                    string type = kid_elem.GetType_(true);
                    if (type == "P")
                    {
                        return(kid_elem);
                    }

                    var paragraph = GetFirstParagraph(kid_elem);
                    if (paragraph != null)
                    {
                        kid_elem.Release();
                        return(paragraph);
                    }

                    kid_elem.Release();
                }
            }
            return(null);
        }
        public static void Run(
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // move paragraph to the back of it's parent
            if (!MoveParagraphToParent(struct_tree))
            {
                throw new Exception("No table found.");
            }

            if (!doc.Save(savePath, Pdfix.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
        }
Пример #8
0
        public static void Run(
            String openPath                             // source PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // read document structure tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                Console.WriteLine("No Tags available");
            }
            else
            {
                for (var i = 0; i < struct_tree.GetNumChildren(); i++)
                {
                    PdsObject        kid_object  = struct_tree.GetChildObject(i);
                    PdsStructElement struct_elem = struct_tree.GetStructElementFromObject(kid_object);
                    ProcessStructElement(doc, struct_elem, "");
                }
            }


            doc.Close();
        }
Пример #9
0
        // process struct element childs and collect all bboxes of the content elements
        // bounding boxes of child elements and content can be placed on different pages
        static List <PdfRect> GetStructElementBboxes(PdfDoc doc, PdsStructElement struct_elem)
        {
            var bboxes   = new List <PdfRect>();
            int num_kids = struct_elem.GetNumKids();

            for (int i = 0; i < num_kids; i++)
            {
                var kid_obj = struct_elem.GetKidObject(i);
                switch (struct_elem.GetKidType(i))
                {
                case PdfStructElementType.kPdsStructKidElement:
                {
                    var kid_struct_elem = struct_elem.GetStructTree().AcquireStructElement(kid_obj);
                    if (kid_struct_elem == null)
                    {
                        throw new Exception(pdfix.GetErrorType().ToString());
                    }
                    bboxes.AddRange(GetStructElementBboxes(doc, kid_struct_elem));
                    kid_struct_elem.Release();
                }
                break;

                case PdfStructElementType.kPdsStructKidObject:
                    break;

                case PdfStructElementType.kPdsStructKidStreamContent:
                case PdfStructElementType.kPdsStructKidPageContent:
                {
                    var kid_page_num = struct_elem.GetKidPageNumber(i);
                    var mcid         = struct_elem.GetKidMcid(i);
                    bboxes.AddRange(GetMcidBBoxes(doc, kid_page_num, mcid));
                }
                break;
                }
            }
            return(bboxes);
        }
        public static void Run(
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }


            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement figure = GetFirstFigure(struct_tree);

            if (figure == null)
            {
                throw new Exception("No figure found.");
            }

            if (!figure.SetAlt("This is a new alternate text"))
            {
                throw new Exception(pdfix.GetError());
            }

            if (!doc.Save(savePath, Pdfix.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
        }
        public static void Run(
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement table = GetFirstTable(struct_tree);

            if (table == null)
            {
                throw new Exception("No table found.");
            }

            PdfRect bbox = new PdfRect();

            GetStructElementBBox(table, ref bbox);

            // remove all items from the table to make it untagged cotnent
            for (int i = table.GetNumChildren() - 1; i >= 0; i--)
            {
                table.RemoveChild(i);
            }

            // tag page
            PdfPage page = doc.AcquirePage(0);

            PdePageMap page_map = page.AcquirePageMap();
            PdeElement elem     = page_map.CreateElement(PdfElementType.kPdeImage, null);

            elem.SetBBox(bbox);
            elem.SetAlt("This is image caption");

            // prepare document template to ignore already tagged content
            var doc_prelight = doc.GetTemplate();

            doc_prelight.SetProperty("ignore_tags", 1);

            // re-tag non-tagged page content
            PdePageMap pageMap = page.AcquirePageMap();

            if (pageMap == null)
            {
                throw new Exception(pdfix.GetError());
            }
            if (!pageMap.CreateElements(null, null))
            {
                throw new Exception(pdfix.GetError());
            }

            if (!page_map.AddTags(table, null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // udpate the table element type
            if (!table.SetType("Sect"))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!doc.Save(savePath, Pdfix.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
        }
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // tag text on the bottom of the page as artifact
            for (int i = 0; i < struct_tree.GetNumKids(); i++)
            {
                PdsObject        kid_obj  = struct_tree.GetKidObject(i);
                PdsStructElement kid_elem = struct_tree.AcquireStructElement(kid_obj);
                TagParagraphAsHeading(kid_elem);
                kid_elem.Release();
            }

            if (!doc.Save(savePath, PdfSaveFlags.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
            pdfix.Destroy();
        }
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement paragraph = GetFirstParagraph(struct_tree);

            if (paragraph == null)
            {
                throw new Exception("No table found.");
            }

            // move paragraph to the back of it's parent
            PdsStructElement parent = struct_tree.AcquireStructElement(paragraph.GetParentObject());

            if (parent == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!paragraph.SetParent(parent, parent.GetNumKids() - 1))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!doc.Save(savePath, PdfSaveFlags.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
            pdfix.Destroy();
        }
        public static void Run(
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            Pdfix pdfix = PdfixEngine.Instance;

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement paragraph = GetFirstParagraph(struct_tree);

            if (paragraph == null)
            {
                throw new Exception("No paragraph found.");
            }

            PdfRect annot_bbox = new PdfRect();

            GetStructElementBBox(paragraph, ref annot_bbox);

            // add new link annotation to the page
            PdfPage      page  = doc.AcquirePage(0);
            PdfLinkAnnot annot = (PdfLinkAnnot)page.CreateAnnot(PdfAnnotSubtype.kAnnotLink, annot_bbox);

            page.AddAnnot(0, annot);
            if (annot == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // re-tag the document the link annotation
            if (!doc.RemoveTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }
            if (!doc.AddTags(null, null))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!doc.Save(savePath, Pdfix.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
        }
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement paragraph = GetFirstParagraph(struct_tree);

            if (paragraph == null)
            {
                throw new Exception("No paragraph found.");
            }

            PdfRect annot_bbox = new PdfRect();

            GetStructElementBBox(paragraph, ref annot_bbox);

            // add new link annotation to the page
            PdfPage      page  = doc.AcquirePage(0);
            PdfLinkAnnot annot = page.AddLinkAnnot(0, annot_bbox);

            if (annot == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // re-tag the document the link annotation
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!doc.Save(savePath, PdfSaveFlags.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
            pdfix.Destroy();
        }
        static void ProcessStructElement(PdsStructElement struct_elem, string indent)
        {
            indent += " ";
            if (struct_elem == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            string type_str = struct_elem.GetType_(true);

            Console.WriteLine(indent + type_str);

            string tile_str = struct_elem.GetTitle();

            Console.WriteLine(indent + tile_str);

            string actual_text_str = struct_elem.GetActualText();

            Console.WriteLine(indent + actual_text_str);

            string alt_str = struct_elem.GetAlt();

            Console.WriteLine(indent, alt_str);

            var page_num = struct_elem.GetPageNumber();

            Console.WriteLine(indent, "Page number: " + page_num);

            int num_kids = struct_elem.GetNumKids();

            for (int i = 0; i < num_kids; i++)
            {
                var kid_obj = struct_elem.GetKidObject(i);
                // based on structure element you can obtain different data
                switch (struct_elem.GetKidType(i))
                {
                case PdfStructElementType.kPdsStructKidElement:
                {
                    var kid_struct_elem = struct_elem.GetStructTree().AcquireStructElement(kid_obj);
                    if (kid_struct_elem == null)
                    {
                        throw new Exception(pdfix.GetErrorType().ToString());
                    }
                    ProcessStructElement(kid_struct_elem, indent);
                    kid_struct_elem.Release();
                }
                break;

                case PdfStructElementType.kPdsStructKidObject:
                    break;

                case PdfStructElementType.kPdsStructKidStreamContent:
                {
                    var kid_page_num = struct_elem.GetKidPageNumber(i);
                    Console.WriteLine(indent + "Kid Page number: " + kid_page_num);
                    var mcid = struct_elem.GetKidMcid(i);
                    Console.WriteLine(indent + "MCID: " + mcid);
                }
                break;

                case PdfStructElementType.kPdsStructKidPageContent:
                {
                    var mcid = struct_elem.GetKidMcid(i);
                    Console.WriteLine(indent + "MCID: " + mcid);
                }
                break;
                }
            }
        }
        public static void Run(
            String email,                               // authorization email
            String licenseKey,                          // authorization license key
            String openPath,                            // source PDF document
            String savePath                             // dest PDF document
            )
        {
            pdfix = new Pdfix();
            if (pdfix == null)
            {
                throw new Exception("Pdfix initialization fail");
            }

            if (!pdfix.Authorize(email, licenseKey))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdfDoc doc = pdfix.OpenDoc(openPath, "");

            if (doc == null)
            {
                throw new Exception(pdfix.GetError());
            }

            // cleanup any previous structure tree
            if (!doc.RemoveTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // autotag document first
            if (!doc.AddTags(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // get the struct tree
            PdsStructTree struct_tree = doc.GetStructTree();

            if (struct_tree == null)
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            PdsStructElement table = GetFirstTable(struct_tree);

            if (table == null)
            {
                throw new Exception("No table found.");
            }

            PdfRect bbox = new PdfRect();

            GetStructElementBBox(table, ref bbox);

            // remove all items from the table to make it untagged cotnent
            for (int i = table.GetNumKids() - 1; i >= 0; i--)
            {
                table.RemoveKid(i);
            }

            // tag page
            PdfPage page = doc.AcquirePage(0);

            PdePageMap page_map = page.CreatePageMap();
            PdeElement elem     = page_map.CreateElement(PdfElementType.kPdeImage, null);

            elem.SetBBox(bbox);
            elem.SetAlt("This is image caption");

            // prepare document template to ignore already tagged content
            PdfDocTemplate doc_tmpl = doc.GetDocTemplate();

            doc_tmpl.SetProperty("ignore_tags", 1);

            // re-tag non-tagged page content
            if (!page_map.AcquireElements(null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }
            if (!page_map.AddTags(table, null, IntPtr.Zero))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            // udpate the table element type
            if (!table.SetType("Sect"))
            {
                throw new Exception(pdfix.GetErrorType().ToString());
            }

            if (!doc.Save(savePath, PdfSaveFlags.kSaveFull))
            {
                throw new Exception(pdfix.GetError());
            }

            doc.Close();
            pdfix.Destroy();
        }