Flattening Transparencies - Gimp, Scribus, and DriveThruRPG - pdf

I used Scribus to create a black and white PDF, including images prepared with Gimp. I submitted the PDF to DriveThruRPG for their print on demand service and it was initially rejected by their printer (Lightning Source). This was the feedback from DriveThruRPG:
the interior file had some PDF/X compliance issues. They ran it
through preflight, flattening transparencies, and the resulting file
worked.
For next time, how do I fix this problem on my end? Here is the workflow that I used:
I received images from various sources, opened them in Gimp, converted them to grayscale, and saved them in EPS format. None of the images contained any transparency that I am aware of. Most of the images consisted of black line art on a white background.
In Scribus I created a document, set the Color to Grayscale, laid out the text, imported the EPS images that I had created with Gimp, and exported the document with Compatibility set to PDF/X-1a.
What would it mean to "flatten transparencies" and at what point in the process would I do that? In Gimp? In Scribus?
Edit:
Okay I see that GIMP has a Flatten Image command which removes the alpha channel. Should I try running that on all of the images before saving them in EPS format?
Could Scribus also be introducing transparency into the PDF somewhere? At this link... Is there a way to flatten a .pdf image from the command line? ...I see this command:
pdf2ps orig.pdf - | ps2pdf - flattened.pdf
Should I also run that on the PDF before sending it to the printer?

Related

imagemagick - generated PDFs are blurry/hazy

I have an image of a website which I'm trying to convert to PDF. I have the image in several formats: PSD, PNG, JPG, TIFF, all saved losslessly.
I'm using the following command to convert the image to PDF:
convert -density 93 foo.jpg bar.pdf
Here is part of the original image:
And here is the same part, after converting to PDF:
As you can see, the second one is ever so slightly hazy. What's causing this, and how can I eliminate it? I've seen PDFs with crisp graphics, so I know it's possible.
If you are seeing the same results with multiple input types. The fuzziness is likely being caused by the anti-aliasing feature of your PDF Viewer. If using Acrobat, you can turn off image anti-aliasing by doing the following:
Go to Edit-->Preferences-->Page Display
Untick the option "Smooth Images" and hit "OK".
The crisp graphics you are seeing on other PDFs are likely due to the fact that they are vectorized graphics. Imagemagick is creating a PDF and embedding your image inside of it which may be subject to compression.
Also:
When using jpeg as input, add the "-quality 100" to your Imagemagick call to retain the highest quality possible.
Use a higher value for the "-density" parameter (I would recommend at least 150) to generate a higher resolution PDF.

PDFClown image extraction images inverted

I'm working with PDFClown and I'm trying to extract images from a pdf file. I use the example code provided by the source code that can be found at http://pdfclown.org.
ImageExtractionSample.java.
The problem is the images are negative and flipped horizontally. Does anyone know how to resolve this problem?
Check with other PDF files to see if other PDF files are also giving the rotated or flipped images. ImageExtractionSample.java is not checking rotation or matrix defined transformations for the image object but just writes the content to a file as is (so it will work for JPG images but not for CCIT encoded images for example).
So there are things to consider when you extract image from PDF:
image can be rotated using the attached transformation matrix (CTM);
image can be rotated/transformed as part of the form which is transformed;
image can be placed without transformation on a page but the page itself is rotated;
image may contain the overlaid Mask on top of it (and the Mask can be rotated and transformed);
JPG image is stored pretty much as is but there are other formats supported by PDF like CCIT compression, LZW compressed images etc;
But the general suggestion is that when you extract JPG image from PDF using PDFClown you should just flip and rotate extracted images like suggested on the SourceForge project discussion page.
if you could point to the particular PDF sample file then it would be easier to suggest the solution.
If you're on Windows then you may use this free PDF Multitool utility to compare non-transformed and transformed images from PDF using "Extract raw images (without transformation)" option in images extraction dialog.
Disclaimer: I work for ByteScout, the PDF Multitool utility is free for both commercial and non-commercial purposes.

Import vector graphics from PDF to GIMP

I need to extract vector graphics from a PDF image and import them into GIMP, either as paths or as high-resolution raster images. Specifically, I need to get contour lines from USGS topographical maps and overlay them on satellite images. Any suggestions?
So far I have tried:
--Using GIMP's native PDF importing function to import them as raster images. Problem: To do so at high resolution crashes my computer. Possible solution would be to import only a selected area of a PDF, but as far as I can tell this is not possible.
--Using ImageMagick to convert the PDF to a raster image. Problem: Used with the "-scale" parameter, "convert" appears to rasterize the PDF and then upscale it, leading to a choppy image.
--Using InkScape to extract the necessary vector elements from the PDF. Problem: InkScape freezes when I try to open a moderately large (25 Mb) PDF.
Any other ideas?
Many thanks,
treacl
The option you didn't mention above is to try to use the ghostscript program directly to render your output - ghostscript is used internally by GIMP to import PDF files, so you likely have it installed already.
There are tens of command switches to pass ghostscript for it to render a file into another format - the switches you need to pass are for determining the output size, resolution and which page to print. I didn't find any switch to select a portion of the page to be rendered - so, if your document is a single page, it is possible the generated file will still be to big for GIMP - but you will likely be able to crop it with ImageMagick, at least.
I guess the relevant command line for you would be something along:
gs -dNOPAUSE -dBATCH -sDEVICE=png16m -sOutputFile=page.png -dFirstPage=<pagenumber> -dLastPage=<pagenumber> -r<dpiresolution> -f<filename.pdf>
If the resulting image is still too large to be generated or operated upon, you can try changing the output format to use a smaller color depth (this one is 3 bytes per pixel: png16m) . It should be possible to pass postscript commands to transform the device, so that the area of interest is scaled up to your page size (and the remaining parts are cropped out of the rendering) - that would be the definitive fix for you - but of the top of my head, I don't know how to do that with ghostscript.
Alternatively, you can try passing ImageMagick the -density parameter as suggested in the comments.

Eps file inside postscript file using ghostscript

I am trying to produce production ready pdf.
I have eps file uploaded by admin and postscript file which I generate dynamically. I include eps with in postscript file
using below script
%%BeginDocument: danske.eps
(".$bgeps_path.") run
%%EndDocument
Now my problem is, there should be 10 mm space around image.
I managed to add 10mm space into pdf via translate.
But when It goes to print, printer cuts two edges, one is with 10mm space and other with image edge.
So what I want is to allow only one edge to cut that is with 10mm space.
I tried to achieve this by playing with BoundingBox but that does help me.
BoundingBox is a comment, nothing more, and as such is usually ignored. If you want to place an EPS then you need to follow the rules for EPS inclusion. You need to set up the Current Transformation Matrix to correctly scale and position the EPS on the canvas at a minimum.
Tech Note 5022 the EPSF sepcification v3.0 has guidelines for importing EPS files on page 13, you really should read this, particularly the co-ordinate system transformation on page 16. The tech note is available here:
http://partners.adobe.com/public/developer/en/ps/5002.EPSF_Spec.pdf

Need help/answers on PDF color seperation

Using the following process:
A PDF is been created by PDFCreator, when a user prints something to the virtual printer
The PDF gets further processed with integrated VBScript handler and passed over to JAVA which does some processing with the PDF content
In the middle of the process an external application is called with the PDF that adds black text and graphics to the PDF
The PDFs are collected and once a week handed over to a print shop that uses a plate for each CMYK
The problem is: the print shop needs a color seperated CMYK PDF, but the added black text & graphics from the external app should be the only content on the K plane (because we want to make a special print effect). All other content which has been printed via PDFCreator should be on CMY plates only, so black must be emulated with those colors.
At the moment we are manually braking the process before calling the external application and seperate the colors via Adobe Creator Pro, but that is no future option because the whole process should work automated.
So basicly I need a way to convert the CMYK PDFCreator PDF to a CMY version only so the external app can throw in as many black K content as needed.
Is the PDF conversion the right direction I'm heading to? Is there any way w/ ghostscript how this can be done? I read the gs documentation but got nowhere as I only saw RGB to CMYK conversion but no CMYK to CMY with empty B...
I believe that PDFCreator is simply a wrapper around ghostscript, so you may have some joy on the ghostscript mailing lists. It seems that gs does support some printers that just ouput CMY so this functionality is likely to be available in there.
Wouldn't you be better off using a new separation called Black? Can't the print shop handle that?