Problem using QuickPDFRenderPageToFile with PNG

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I am guessing the PDF developer of this PDF file made a wrong assumption and used 4544 x 4064 as the width and height.  The image in this file is actually 4544 x 4064 pixels in size so I am pretty sure this is why the page dimensions are wrong and why the image is so big.

The pageWidth/pageHeight are normally measured in points (72 points = 1 inch) and so the 4544 x 4064 needed to be scaled to points. ie.  1090 x 975.  This image is 300 dpi so 4544 / 300 * 92 = 1090 and 4064 / 300 * 72 = 975.

Using QPL to Render this file with the invalid page size consumed a 1 GB of memory.  It did render ok on my 8GB machine.  So some of the other ideas to render large files would be useful.

Andrew.

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AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Topic: Problem using QuickPDFRenderPageToFile with PNG Posted: 11 Apr 11 at 9:08AM
	I am guessing the PDF developer of this PDF file made a wrong assumption and used 4544 x 4064 as the width and height. The image in this file is actually 4544 x 4064 pixels in size so I am pretty sure this is why the page dimensions are wrong and why the image is so big. The pageWidth/pageHeight are normally measured in points (72 points = 1 inch) and so the 4544 x 4064 needed to be scaled to points. ie. 1090 x 975. This image is 300 dpi so 4544 / 300 * 92 = 1090 and 4064 / 300 * 72 = 975. Using QPL to Render this file with the invalid page size consumed a 1 GB of memory. It did render ok on my 8GB machine. So some of the other ideas to render large files would be useful. Andrew.

darkv Members Profile Find Members Posts Team Player Joined: 17 Jan 11 Status: Offline Points: 38	Post Options Post Reply Quote darkv Report Post Thanks(0) Quote Reply Posted: 08 Apr 11 at 11:14PM
	Pedro, Why don't you use a Windows DC to clip your image (or a part of), and then you "band" your image to reduce the size you have to deal with (as printer does when it process a big file) When you create the DC you can define the resolution for your device. My fear is memory consumption for such an image, but could be a workaround. please find below part of a vb.net code i used. Hope this helps Rgds Dim bmp As New Bitmap(iPw, iPH, System.Drawing.Imaging.PixelFormat.Format32bppArgb) gDisp = Graphics.FromImage(bmp) hDCd = gDisp.GetHdc ' lRtn = zPdf.RenderPageToDC(72, 1, hDCd) ' DPI settings Ps : dont forget to ".release" and ".dispose" variables ;-)

PedroLamas Members Profile Find Members Posts Beginner Joined: 07 Apr 11 Location: Portugal Status: Offline Points: 2	Post Options Post Reply Quote PedroLamas Report Post Thanks(0) Quote Reply Posted: 08 Apr 11 at 10:38AM
	Greetings Ingo, First of all, let me thank you for your reply! :) I know the original page is 4544x4064, but I really need it at 150dpi because this page (and others a little less "noisy") will be used for OCR/ICR, and 150dpi is the minimum DPI's we need to get an accurate result! The problem is that if I output it as a BMP at 150dpi, it creates a file bigger that 200Mb, as for PNG the file will be at max 10Mb! I'll make a post for a bug in the official support pages (I thought this was it, though, sorry!!) Regards, Pedro Lamas

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 07 Apr 11 at 6:40PM
	Hi Pedro! The page size from your pdf is 4544 x 4064 pixels. A "normal" page size is 842 x 595 means (in german DIN A4). with 72 dpi the size will be the same - with 100 or 150 it will be larger. Seems that the included png-routines are not made for images with a size about 1.4 x 1.6 meters ;-) If you're the meaning that this is a bug you should post it at the official support pages. Cheers, Ingo

PedroLamas Members Profile Find Members Posts Beginner Joined: 07 Apr 11 Location: Portugal Status: Offline Points: 2	Post Options Post Reply Quote PedroLamas Report Post Thanks(0) Quote Reply Posted: 07 Apr 11 at 2:48PM
	Greetings, I'm new to your forum, but the company I work on has bought and been using QuickPDF for a while now, always with full success!! :) But yesterday, I came up with a problem: I have a file that I need to output its pages to PNG at 150dpi, but this seems to throw an exception (I'm using .NET 4.0 with Interop to QuickPDF 0724) If I use: QuickPDFRenderPageToFile(instanceID, 150, 1, 5, fileName); //PNG at 150dpi this will raise an exception, but the following commands will work ok: QuickPDFRenderPageToFile(instanceID, 100, 1, 5, fileName); //PNG at 100dpi QuickPDFRenderPageToFile(instanceID, 150, 1, 0, fileName); //BMP at 150dpi QuickPDFRenderPageToFile(instanceID, 150, 1, 1, fileName); //JPEG at 150dpi QuickPDFRenderPageToFile(instanceID, 150, 1, 7, fileName); //TIFF at 150dpi Can you help me with this one please? :) You can get the file I'm using that gives this problem here: http://cid-b26d27fb6d61bde4.office.live.com/self.aspx/Public/d5514f41-5d7f-400a-837e-129041f480ee^_001.pdf Best regards and please keep up with your good work!!! Pedro Lamas