Rerender existing PDFs

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Hello all, 
i have PDF files containing elements (Rectangles, Texts, etc. - no images!) in the RGB color space. I need to convert these PDFs to the CMYK color space. Is there any possibility to somehow convert existing PDFs or iterate through them redrawing them to new files or anything else that I could use in order to receive PDFs in CMYK color space?

Regards,
Martin

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martin.weigl Members Profile Find Members Posts Team Player Joined: 23 Feb 16 Location: Upper Austria Status: Offline Points: 27	Post Options Post Reply Quote martin.weigl Report Post Thanks(0) Quote Reply Topic: Rerender existing PDFs Posted: 07 Apr 16 at 1:44PM
	Hello all, i have PDF files containing elements (Rectangles, Texts, etc. - no images!) in the RGB color space. I need to convert these PDFs to the CMYK color space. Is there any possibility to somehow convert existing PDFs or iterate through them redrawing them to new files or anything else that I could use in order to receive PDFs in CMYK color space? Regards, Martin

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 16 at 8:39PM
	Hi Martin, About manual converting/calculating RGB-values to CMYK you can read in this thread: http://www.quickpdf.org/forum/edit-pdf-text_topic1378.html For example to set the text color in CMYK you can use SetTextColorCMYK: http://www.debenu.com/docs/pdf_library_reference/SetTextColorCMYK.php In the online reference you'll find in the section "color" many CMYK-functions: http://www.debenu.com/docs/pdf_library_reference/Color.php
	Cheers, Ingo

martin.weigl Members Profile Find Members Posts Team Player Joined: 23 Feb 16 Location: Upper Austria Status: Offline Points: 27	Post Options Post Reply Quote martin.weigl Report Post Thanks(0) Quote Reply Posted: 21 Apr 16 at 12:22PM
	Hi Ingo, thx for ur reply. The info was not exactly what I was looking for: I need to convert elements of existing PDF files from the RGB color space into colors of the CMYK color space. If there is some way to do so (i. e. render the existing PDF element-by-element into a new one converting the colors), please let me know. Is there a way to fetch all elements (rectangles, circles, texts, etc.) out of a PDF file? Regards, Martin Edited by martin.weigl - 21 Apr 16 at 12:22PM

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: 21 Apr 16 at 9:22PM
	Hi Martin, embedded images you can extract from pdf-pages, converting them outside with other third party tools. Rectangles, circles and so on are not graphic objects but only scriptcode - you can't extract things like this.
	Cheers, Ingo

martin.weigl Members Profile Find Members Posts Team Player Joined: 23 Feb 16 Location: Upper Austria Status: Offline Points: 27	Post Options Post Reply Quote martin.weigl Report Post Thanks(0) Quote Reply Posted: 22 Apr 16 at 7:58AM
	Hi Ingo, thx for ur reply. The problem is (as you mentioned [URL=http://www.quickpdf.org/forum/topic3314_post13194.html#13194]here[URL]), that the PDFs metadata identifies the PDF as "CMYK", alltough it has some RGB elements embedded. That's the problem that I need to detect (without correcting it, simply detecting ist is enough). Regars, Martin

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: 22 Apr 16 at 10:28PM
	Hi Martin, it's not difficult. Take few relevant pdf-files and have a look directly inside with - for example - notepad. Keep in mind the relevant devicetags you've found. Then you can build a routine... reading the pdf-file into a stream and doing a fulltextsearch (with your tags) on the stream. Additionally you should search for strings like <</BitsPerComponent /ColorSpace 291 <</BitsPerComponent 8/ColorSpace 291 or rdf-content like this: dc:format="image/jpeg" ...or any other similar string. What i've found searching for you in ONE pdf was the next: <</BitsPerComponent 8/ColorSpace 293 ...and few lines later: <</BitsPerComponent 8/ColorSpace/DeviceRGB/ ...and later this: <</BitsPerComponent 8/ColorSpace/DeviceGray/ To determine if coloured objects were used or if device-tags were used can be a different issue.
	Cheers, Ingo

martin.weigl Members Profile Find Members Posts Team Player Joined: 23 Feb 16 Location: Upper Austria Status: Offline Points: 27	Post Options Post Reply Quote martin.weigl Report Post Thanks(0) Quote Reply Posted: 25 Apr 16 at 1:12PM
	Hi Ingo, thx for your help! Regards, Martin