Create Thumbnails

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I would like to create thumbnails for each page in a PDF.  These thumbnails need to be JPEG and I would expect them to be 2 - 8 kb is size.  See the following code for the things that I have tried. 
int DocumentID = qp.LoadFromFile(fullFileName, "");
int iNumPages = qp.PageCount();

for (int i = 1; i <= iNumPages; i++)
{
    tmpTNFilename = Set thumbnail filename for this page

    qp.SelectPage(i);
    qp.NormalizePage(0);

    // Gave me just part of the lower left corner
    //sizeDouble = QPDFUtilities.GetImageSize(qp, thumbnailData);
    //qp.SetPageDimensions(sizeDouble.WidthDouble, sizeDouble.HeightDouble);

    // When opened in a viewer still gives me a full page and the file size is too large
    //qp.SetPageThumbnail();

    // When opened in a viewer still gives me a full page and the file size is too large
    scale = QPDFUtilities.GetImageScale(qp, thumbnailData);
    qp.SetScale(scale);

    qp.RenderPageToFile(96, i, 1, tmpTNFilename);
    thumbnailData.ThumbnailPaths.Add(tmpTNFilename);
}

qp.RemoveDocument(DocumentID);

So what I am seeing is the resulting file size is too large and the image when displayed in a viewer is still a full page.  Recommendations as to how I can use your available API to achieve the small file size.  Or should I render each page to a JPEG and then just use .Nets System.Drawing.Image to create the thumbnails?

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moakley Members Profile Find Members Posts Beginner Joined: 23 Oct 12 Status: Offline Points: 9	Post Options Post Reply Quote moakley Report Post Thanks(0) Quote Reply Topic: Create Thumbnails Posted: 30 Apr 13 at 2:06PM
	I would like to create thumbnails for each page in a PDF. These thumbnails need to be JPEG and I would expect them to be 2 - 8 kb is size. See the following code for the things that I have tried. int DocumentID = qp.LoadFromFile(fullFileName, ""); int iNumPages = qp.PageCount(); for (int i = 1; i <= iNumPages; i++) { tmpTNFilename = Set thumbnail filename for this page qp.SelectPage(i); qp.NormalizePage(0); // Gave me just part of the lower left corner //sizeDouble = QPDFUtilities.GetImageSize(qp, thumbnailData); //qp.SetPageDimensions(sizeDouble.WidthDouble, sizeDouble.HeightDouble); // When opened in a viewer still gives me a full page and the file size is too large //qp.SetPageThumbnail(); // When opened in a viewer still gives me a full page and the file size is too large scale = QPDFUtilities.GetImageScale(qp, thumbnailData); qp.SetScale(scale); qp.RenderPageToFile(96, i, 1, tmpTNFilename); thumbnailData.ThumbnailPaths.Add(tmpTNFilename); } qp.RemoveDocument(DocumentID); So what I am seeing is the resulting file size is too large and the image when displayed in a viewer is still a full page. Recommendations as to how I can use your available API to achieve the small file size. Or should I render each page to a JPEG and then just use .Nets System.Drawing.Image to create the thumbnails?