Change ImageResolution

Hi,

I must reduce the filesize of my PDFs and save as new one.
How can I change the imageresolution of alle images to 72 dpi wit QuickPDFLibrary?

This code don't do this

private static void resizePDF(string source, string target)
        {
            PDFLibrary QP = new PDFLibrary(@"QuickPDFDLL0816.dll");
            string licenseKey = "...licensekey...";
            QP.UnlockKey(licenseKey);

            int FileHandle = QP.LoadFromFile(source, "");
            int numPages = QP.PageCount();
            int numImages = QP.FindImages();
            for (int i = 1; i <= numPages; i++)
            {
                for (int j = 1; j <= numImages; j++)
                {
                    int idxImage = QP.GetImageID(i);
                    QP.SelectImage(idxImage);
                    QP.SetImageResolution(72,72,2);
                }
            }

            QP.SaveToFile(target);
        }


Regards
Karsten


Edited by Karsten - 08 Apr 13 at 8:37AM