Simple and Free PDF to Image Conversion

Download source files - 509 KB

Introduction

This article is about extracting image files from a PDF file. I was looking for a free solution for converting .pdf files to image files, but I didn't find a simple and free solution. I therefore tried until I found a free solution by using the "Adobe Acrobat COM component" and using the CAcroPDDoc class.

Pre-requisites

You must have "Adobe Acrobat Reader" installed on your system. My system had Adobe Acrobat 9.0 installed.

Using the code and description

First, I added a reference to the Adobe Acrobat COM component.

I then wrote the PDFConvertor class that has a method named Convert(....) which would do the conversion. Here is the code in my class used for accessing a PDF document:

Acrobat.CAcroPDPage pdfPage = null;//the pdf page
Acrobat.CAcroRect pdfRect = new Acrobat.AcroRect();//the pdf region
Acrobat.AcroPoint pdfPoint =new Acrobat.AcroPoint();//the pdf point

CAcroPDDoc class is for working with the PDF file
CAcroPDPage class is for working with the pages in the PDF file
CAcroRect and AcroPoint classes are for defining the dimensions of a page

Here is how I open a PDF document:

if (pdfDoc.Open(sourceFileName))//check file is opened?

For opening a specified PDF file, I use the open() method of the pdfDoc object; it returns false in the case of an error.

pageCount = pdfDoc.GetNumPages();//get the count of pdf pages

After reading the page count with pdfDoc.GetNumPages(), I then read a page.

pdfPage = (Acrobat.CAcroPDPage)pdfDoc.AcquirePage(i); //reading current page

Then, I extract a pages in the PDF file using pdfDoc.AcquirePage(i) and assign it to the pdfPage object; the variable i indicates the number of the current page.

pdfPoint = (Acrobat.AcroPoint)pdfPage.GetSize();//geting page size
pdfRect.Left = 0;
pdfRect.right = pdfPoint.x;
pdfRect.Top = 0;
pdfRect.bottom = pdfPoint.y;

I then get the page size with pdfPage.GetSize() and put it into a pdfPoint object. This is required for specifying the region of the PDF page for copying the page into the Clipboard.

pdfPage.CopyToClipboard(pdfRect, 0, 0, 100);//coping region to clipboard

Make sure that pdfPage doesn't have any method for saving as the referenced page. pdfPage.CopyToClipboard(pdfRect, 0, 0, 100) can help us there. It has four arguments: first is the rect of the page that was previously discussed, second and third are x, y offsets of the page that usually are 0, and fourth is the zoom percent.

Clipboard.GetImage().Save(outimg, outPutImageFormat);// saving clipboard image

Finally, with Clipboard.GetImage().Save(...), we can save the output image.

Here is the code for the Convert method of my class:

#region Convert
/// 
/// Converting PDF Files TO Specified Image Format
/// 
/// sourceFileName : Source PDF File Path
/// DestinationPath : Destination PDF File Path
/// outPutImageFormat: Type Of Exported Image
/// Returns Count Of Exported Images
public int Convert(string sourceFileName, 
       string DestinationPath, ImageFormat outPutImageFormat)
{
    if (pdfDoc.Open(sourceFileName))
    {
        // pdfapp.Hide();
        pageCount = pdfDoc.GetNumPages();

        for (int i = 0; i < pageCount; i++)
        {
            pdfPage = (Acrobat.CAcroPDPage)pdfDoc.AcquirePage(i);

            pdfPoint = (Acrobat.AcroPoint)pdfPage.GetSize();
            pdfRect.Left = 0;
            pdfRect.right = pdfPoint.x;
            pdfRect.Top = 0;
            pdfRect.bottom = pdfPoint.y;

            pdfPage.CopyToClipboard(pdfRect, 500, 110, 100);

            string outimg = "";
            string filename=sourceFileName.Substring(
                       sourceFileName.LastIndexOf("\\")); 

            if (pageCount == 1)
                outimg = DestinationPath + "\\" + filename + 
                  "." + outPutImageFormat.ToString();
            else
                outimg = DestinationPath + "\\" + filename + 
                  "_" + i.ToString() + "." + outPutImageFormat.ToString();
            
            Clipboard.GetImage().Save(outimg, outPutImageFormat);

            ////////////Firing Progress Event 
            OnExportProgressChanging(outimg);
        }

          Dispose();
    }
    else
    {
        Dispose();
        throw new System.IO.FileNotFoundException(sourceFileName + 
                  " Not Found!");
    }
    return pageCount;
}
#endregion

I have also implemented a class for indicating the progress with the event handler ProgressChangingEventHandler that exists in the source of my project.

Enjoy!