Adjust the size of a scanned pdf page based on the original.

Question

There is a way to adjust the size of a scanned pdf page based on the size of the original page content. Both are in A4 but the content on the page does not have the same position and scale.

The procedure I have tried so far is this:
Reading the original document and the scanned document.
The scanned document is passed into OCR processor.
Search for a common text of both (for example a keyword)

based on the position of the keyword and its size, I tried to readjust the content but with poor results.

PdfLoadedDocument loadedDocumentModello = new PdfLoadedDocument(helperModello.DocumentStream); -- Original pdf

PdfLoadedDocument lDoc = new PdfLoadedDocument(helper.DocumentStream); -- Scanned pdf

                                Dictionary<int, List<RectangleF>> pppRectagli = new Dictionary<int, List<RectangleF>>();
                                Dictionary<int, List<RectangleF>> pppRectagliModello = new Dictionary<int, List<RectangleF>>();
                                using (OCRProcessor processor = new OCRProcessor(System.Configuration.ConfigurationManager.AppSettings[@"pathmTesseractBinaries"]))
                                {
                                    processor.Settings.Language = "en";
                                    processor.Settings.TesseractVersion = TesseractVersion.Version4_0;
                                    processor.Settings.EnableNativeCall = true;
                                    processor.Settings.Performance = Performance.Slow;
                                    processor.Settings.OCREngineMode = OCREngineMode.LSTMOnly;
                                    //processor.Settings.IsRegionMarked = true;

                                    string ocr = processor.PerformOCR(lDoc, System.Configuration.ConfigurationManager.AppSettings[@"pathmTesseract"], true);

                                    MemoryStream stream3 = new MemoryStream();
                                    // Saves the document as stream
                                    lDoc.Save(stream3);
                                    lDoc.Close();
                                    // Converts the PdfDocument object to byte form.
                                    byte[] docBytes3 = stream3.ToArray();
                                    helper.Load(docBytes3);
                                    lDoc = new PdfLoadedDocument(helper.DocumentStream);

                                    lDoc.FindText("WORD:", out pppRectagli);
                                    loadedDocumentModello.FindText("WORD:", out pppRectagliModello);

                                    List<RectangleF> fff = pppRectagli[0];
                                    List<RectangleF> fffmodello = pppRectagliModello[0];
                                    float XfinaleDif = fff[0].X - fffmodello[0].X;
                                    float YfinaleDif = fff[0].Y - fffmodello[0].Y;
                                    float HfinaleDif = fff[0].Height - fffmodello[0].Height;
                                    float WfinaleDif = fff[0].Width - fffmodello[0].Width;

                                    //float scale = Math.Min(fffmodello[0].Width / fff[0].Width, fffmodello[0].Height / fff[0].Height);
                                    PdfDocument document = new PdfDocument();
                                   // SizeF pppssssddd = new SizeF(lDoc.Pages[0].Size.Width * (fffmodello[0].Width / fff[0].Width), lDoc.Pages[0].Size.Height
                                    //     * (fffmodello[0].Height / fff[0].Height));

                                    document.PageSettings.Size = lDoc.Pages[0].Size;
                                    document.PageSettings.Margins.All = 0;
                                    document.EnableMemoryOptimization = true;
                                    for (int i = 0; i < lDoc.Pages.Count; i++)
                                    {
                                        PdfPage page = document.Pages.Add();
                                        PdfGraphics g = page.Graphics;

                                        g.ScaleTransform((fffmodello[0].Width / fff[0].Width), fffmodello[0].Height / fff[0].Height);
                                        PdfPageBase lpage = lDoc.Pages[i];
                                        PdfTemplate template = lpage.CreateTemplate();
                                        float X = lDoc.Pages[i].Graphics.Size.ToPointF().X;
                                        float Y = lDoc.Pages[i].Graphics.Size.ToPointF().Y;
                                        PointF poin = new PointF(- XfinaleDif, - YfinaleDif);
                                        g.DrawPdfTemplate(template, poin, g.Size);
                                    }



                                     MemoryStream stream = new MemoryStream();
                                    // Saves the document as stream
                                    document.Save(stream);
                                    document.Close();
                                    lDoc.Close(true);
                                    // Converts the PdfDocument object to byte form.
                                    byte[] docBytes = stream.ToArray();
                                    helper.Load(docBytes);
                                    lDoc = new PdfLoadedDocument(helper.DocumentStream);

Gowthamraj Kumar · Accepted Answer

Hi Giovanni,  
  
Thank you for your patience.  
  
We have created a sample to achieve your requirement to adjust the size of a scanned pdf page based on the original. We have attached the attached the sample for your reference. Please find the sample from below link, 
 
Sample: https://www.syncfusion.com/downloads/support/forum/165353/ze/Sample-91409398 
 
Kindly please try the above sample on your end and let us know if it is satisfies your requirement or not. 
 
Regards,  
Gowthamraj K

Gowthamraj Kumar · Answer

Hi Giovanni, 
 
Thank you for contacting Syncfusion support. 
 
We have checked the reported issue with our test document using provided details on our end, the final output document content are slightly differ position from the original document.  We have attached the sample and output document for your reference. Kindly please confirm whether you are reported issue is same like below documents, 
Document: https://www.syncfusion.com/downloads/support/forum/165353/ze/Document899328771 
Sample: https://www.syncfusion.com/downloads/support/forum/165353/ze/OCRPDF_Sample-2075365524 
 
Meanwhile, kindly please share the input and output document with us to check the reported issue on our end. So, that it will be helpful for us to analyze and assist you further on this. 
 
Regards, 
Gowthamraj K

Giovanni · Answer

HelloThanks for the reply.I cannot match the origin of the content and the scale, when, for example, the pdf has been printed with the "adapt content" settingattached the original model and the scanned oneAttachment: model_pdf_996879de.zip

Gowthamraj Kumar · Answer

Hi Giovanni, 
 
Thank you for sharing the details. 
 
We were able to reproduce the reported issue with provided details on our end. Currently, we are validating on this and we will update the further details on May 18th 2021. 
 
Regards, 
Gowthamraj K