Anyone know the right places to hook into ghostscript, so that when interpreting a ps file, I can get logs of all calls of the form:
draw_character(float x, float y, string font_name, int char_id); ?
Basically I want to take a postscript file, and get a list of where all characters are drawn to the screen.
Thanks!
I'm not sure if this answer is going to help you... but do you know how to harvest debugging information from Ghostscript on the commandline? Simply add "-dDEBUG" to the commandline and it will spit out lots of additional info. To get debugging info from only specific topics, you have these options:
-dCCFONTDEBUG Compiled-in Fonts
-dCFFDEBUG CFF Fonts
-dCMAPDEBUG CMAP
-dDOCIEDEBUG CIE color
-dEPSDEBUG EPS handling
-dFAPIDEBUG Font API
-dINITDEBUG Initialization
-dPDFDEBUG PDF Interpreter
-dPDFOPTDEBUG PDF Optimizer (Linearizer)
-dPDFWRDEBUG PDF Writer
-dSETPDDEBUG setpagedevice
-dSTRESDEBUG Static GS Resources
-dTTFDEBUG TTF Fonts
-dVGIFDEBUG ViewGIF
-dVJPGDEBUG ViewJPEG
Possibly, a PostScript programmer guru could write a little PostScript program that could do what you want by re-defining one of the operators (showglyph?) in a way that it prints out the info you want instead of (or before) drawing each individual character and run that against your target PS file.
Maybe you should ask your question in comp.text.pdf or in comp.lang.postscript ?
Related
Is there an option for to me to ask Ghostscript to indent the Postscript it creates?
Everything starts at the beginning of a line and I find it difficult to follow.
Alternatively, I am using Emacs and ps-mode.
If anyone know how to indent code in this mode I would appreciate a tip (apologize because this may not be relevant to this StackExchange)
No, there is no option for indenting the output.
PostScript is pretty much regarded as a write-only language anyway, and the output of ps2write (which is what I assume you are using though you don't say) is particularly difficult since it fundamentally outputs PDF syntax with a PostScript program on the front to parse it into PostScript operations.
Why do you want to read it ?
[EDIT]
You can always edit your question, you don't need to post a new answer.
I'm afraid what you want to do isn't as simple as you might think.
It might be possible for this use case if the PDF files you receive are always created the same way, but there are significant problems.
The font you use as a substitute for the missing font must be encoded the same way. Say for example the font in the PDF file is encoded so that 0x41 is 'A', you need to make sure that the replacement font is also encoded so that 0x41 is an 'A'. So just the findfont, scalefont, setfont sequence is not always going to be sufficient, sometimes you will need to re-encode the font.
CIDFonts will be a major stumbling block. Firstly because ps2write simply doesn't emit CIDFonts at all. These were not part of level 2 PostScript. As a result all text in a CIDFont will be embedded as bitmaps. If your original file doesn't contain the CIDFont then you'll get the fallback CIDFont bitmapped.
Secondly CIDFonts can use multiple-byte character codes, of variable length. You can't simply replace a CIDFont with a Font, it just won't work.
The best solution, obviously, is to have the PDF files created with the fonts required embedded. This is best practice. If you can't get that, then I'd suggest that rather than trying to hand edit PostScript, you use the fontmap.GS and cidfmap files which Ghostscript uses to find font.
Ghostscript already has a load of code to do font substitution automatically, using both Fonts and CIDFonts as substitutes, and it does all the hard work of re-encoding the fonts or building CMaps as required. If you are on Windows much of this may already be done for you, when you install Ghostscript it will ask if you want to create font mappings. If you said yes then it will
Add the font substitutions you want to use in those files (they have comments explaining the layout) and then use the pdfwrite device to make a new PDF file. Set EmbedAllFonts to true (you may need to add a AlwayEmbed font array as well, listing the fonts specifically) and SubsetFonts to false.
That should create a new PDF file where the missing fonts have been replaced by your defined substitutes, those substitutes will have been embedded in the new PDF file and they have will not been subset (Acrobat will generally refuse to edit text in a subset font).
The switches I mentioned above are standard Adobe Distiller parameters, but they are documented for pdfwrite here. There's some documentation on adding fonts here and here and specifically for CIDFonts here.
Basically I'd suggest you define your substitutions and let Ghostscript do the work for you.
This is not an answer to the problem but rather an answer to KenS's question about "Why do you want to read it?"
I tried to put it in the comment box but it was too long.
I am a retired engineer with a strong programming background.
I would like to read and understand the postscript code for the reason shown below.
I play duplicate bridge as a hobby. I recieve a PDF file of what is know as a convention card (a single page document of bridge agreements).
Frequently I would like to edit these files.
When I open with Adobe Illustrator I have to spend a significant amount of time replacing fonts that are not on my system with fonts that I do have.
I can take the PDF and export it as a postscript file using Ghostscript.
I was going to write a little program to replace the embedded fonts with the fonts that I use to replace them.
I was going to leave the postscript file unaltered and insert things like
/HelveticaMonospacedPro-RG findfont
12 scalefont setfont
just above where the text is written.
I was planning on using the fonts that I have on my system (e.g., HelveticaMonospacedPro-RG).
I would like to create a postscript or pdf figure with enhanced notations, italic or bold Latin characters, and sometimes (regular) Greek characters. How to do that in general?
Let's say I downloaded CMU Sans Serif, a font that has glyphs for all the strange characters I ever want to use. I converted them to pfa with an online tool and copied the files to the path of working directory.
Expectations
Let's say I'd like to produce the following notation somewhere.
What I tried: original
I create a gnuplot script encoded in a utf-8 file (without BOM) with the content
set term postscript eps enhanced "CMUSansSerif" 15 fontfile add 'CMUSansSerif.pfa' fontfile add 'CMUSansSerif-Oblique.pfa' fontfile add 'CMUSansSerif-Bold.pfa'
set encoding utf8
set o "print.eps"
p x t "Label: {/CMUSansSerif-Bold important }{/CMUSansSerif-Oblique note}: ∫⟨α₂ + β²⟩ = äßű"
set o
and executed with the newest gnuplot, version 5.2.6.
What I got
I used a vector graphics editor to open the eps file and relevant part looks like this:
What I also tried
According to Ethan's answer I added adobeglyphnames to the termoptions. It made at least the letters available but other Unicode symbols are still unavailable. The result is:
Question
What went wrong? How could I produce the desired output?
So many possibilities, where things can go wrong: Is the font not suitable for this task? Did I download a wrong version of it? Did the pfa converter do a bad job? Did I include the font files incorrectly? Was there something wrong with the set encoding? Do I use a bad vector graphics editor? Do I have wrong fonts installed and the vector graphics editor tries to use them?
I am afraid that the answer is that in general PostScript is the wrong tool for this. If it is at all possible for you to work with PDF output instead, I suggest you do that. It is even possible the resulting PDF file can be translated to a PostScript file by standard tools (e.g. pdf2ps). That is likely to work if the non-ascii characters are limited to Greek and other relatively common symbols but I don't know how much of the full unicode tables are covered by those standard tools.
If you really need to produce PostScript with additional unicode characters directly from gnuplot, you can find full instructions and sample character encoding tables in the gnuplot distribution files:
.../term/PostScript/unicode_maps.README
.../term/PostScript/unicode_big.map
.../term/PostScript/unicode_small.map
I am not familiar with the online tool font conversion you used but probably it failed because it did not have, or at any rate did not use, suitable character encoding tables for the desired conversion.
===
One other thought. There are two ways that a *.pfa font can encode unicode characters that are common enough to have a name assigned by Adobe for use in PostScript. (1) It may use generic names like uni0439 for Unicode code points. (2) It may use Adobe-specific names from the list here:
agl-aglfn glyph list
When selecting PostScript output from gnuplot you can tell it which of these two conventions is used by the font you provide. The default is "noadobeglyphnames".
set term postscript {no}adobeglyphnames
==
(recipe for using "set term pdfcairo")
Font handling is unfortunately system-specific, so I cannot tell you how to install or configure fonts on all your target machines. I will show you a procedure that works on a linux desktop that uses the fontconfig utilities for system font handling.
Create directory /home/share/fonts/CMUSans
Add this directory to the search list in file /etc/fonts/local.conf
Copy *.ttf files into this directory from the CMU Sans Serif zip archive you link to in your original query. The system fontconfig system tools should now be able to find these fonts. By inspection they self-report as "CMU Sans Serif"
in gnuplot (tested with version 5.2.6)
set term pdfcairo font "CMU Sans Serif,15"
set output 'enhanced_utf8.pdf'
load 'enhanced_utf8.dem'
convert output pdf file to PostScript with the following command
pdf2ps enhanced_utf8.pdf enhanced_utf8.ps
Screenshot of the result is shown below
It seems that CMU Sans Serif doesn't contain the UTF-8 characters you are asking for. Check the font with a font editor like Birdfont. Although the webpage shows symbols you want to use, the font itself does not contain them. However, your browser may show symbols, but they are just fallback representations from other fonts.
Good day,
We print Postscript files directly on industrial Xerox printers.
One client's Postscript files were getting garbled due to a font issue that I was unable to track down, so I used Adobe's Distiller to convert from PS to PDF. The same font issues turned up in the PDFs that were generated from Distiller. No amount of option tweaking helped me out, and find/replace font operations using the Callas pdfToolbox didn't work out for me.
So, I downloaded Ghostscript and spent an entertaining hour remembering how DOS worked. I was eventually able to convert several PS files into flawless-looking PDFs by going to the Ghostscript directory and doing this:
gswin64 -dQUIET -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=myoutputfilename.pdf myinputfilename.ps
But, I didn't think things all the way through because now I'm faced with the problem of mixed-plex. Some of the documents in the file are one-page documents and some are two-page documents, which should be printed duplex.
PS handles all of this for us when we put it on one of the Xerox printers. PDF, of course, does not. I can only specify simplex or duplex on the printer - so it's either one or the other, which doesn't work for a PDF with both.
Is there any clean, (or dirty), way to get around this? I was thinking of somehow instructing Ghostscript to insert blank pages after every simplex page of a PS file, and then just printing the entire PDF duplex, but have no idea how I would begin to do this.
Any assistance greatly appreciated. :)
It 'sounds like' you have concatenated several PostScript program together here, is that the case ?
This isn't really a great idea, it can lead to incorrect output, I wonder if this is the source of your problem with Distiller and your printer.
Have you tried producing PostScript instead of PDF, by using the ps2write device instead of pdfwrite ? While this won't carry any of the device-specific controls (such as /Duplex), you can easily put them back. In fact recent versions of the device will allow you to specify code to be inserted at document and/or page level.
Am using GhostScript.Net 1.2.0 version. Am converting a pdf file into list of images to print. My Printed image height and width is fine but the printed image quality is poor. Please help me how to improve the image quality while converting a pdf to image using ghostscript.net
You need to either take this up with the Ghostscript.Net maintainer or find some way to tell us what command line/configuration you are using (ALL of it!), you will also need to supply an example file and define what you find objectionable in your current prints. 'image quality is poor' is extremely subjective, not helpful at all, there could be many, many reasons for 'poor quality', starting with your input file.
You also need to state what operating system you are using, and what your printing setup is. If you have tried anything already, then you need to say what you have done or we will waste much time suggesting dead ends.
Note that if you are using the mswinpr2 device, there may be little that can be done as that relies on the printer driver in the Windows system to do the actual printing.
I am trying to create my own tool for creating the pdf file. Every thing is going well, Only thing I miss is the font descriptors. Kindly let me know the correct values of capheight, ascent, descent, glag, italic angle from afm/pfa/pfb or any tool available to genrate the same
Fontographer will show those values. A bit pricey for just collecting statistics. My copy is old, back when Macromedia owned it. FontLab does now. See http://www.fontlab.com/font-editor/fontographer/