Re: [NTG-context] Change color of EPS file.
2012/9/15 Troy Henderson thend...@gmail.com: Utilities are available in abundance which can transform raster graphics from color to grayscale, but until I created this yesterday, I have never seen a utility that keeps the graphic in vector format (i.e., never rasterizes it throughout the conversion) and converts it from color to grayscale. Until I read this thread, I guess I thought I was the only one that desired such a tool. I'm glad to see that at least I'm not alone. Oh, there are, but I know only commercial (e.g. OneVision Asura) or in-house solutions (like what I managed at a newspaper several years ago). The simple (or simplistic) rgbcolor patch doesn't work with complicated EPS, of course. But then you'd need to know the structure of your EPS. It's hard to get that right for arbitrary EPS. And there aren't that many able PostScript programmers left. E.g. at that newspaper we were able to switch spot colors just before plate exposition; the trick was to use a generic spot color name throughout the workflow and to change its definition in the completed page EPS. (At that time our printing press was too small to print all pages in full color.) Since PostScript is a full programming language, most PS generators use shortcuts (macros/functions) that wrap the originally simple commands, so you often can't track down where the structure hides that you'd like to change. Best solution is often to do a full expansion with a PS interpreter and write a new, better readable, but mostly much bigger code. pstoedit is your friend for that – e.g. Hans did some nice tricks with EPS pictures converted to MetaPost. I once experimented a bit with changing colors of embedded bitmap images – it's rather easy to do, but never looks right without a deep understanding of color management and its strange implementation in PostScript... Greetlings, Hraban ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
On Sep 15, 2012, at 1:36 AM, luigi scarso luigi.sca...@gmail.commailto:luigi.sca...@gmail.com wrote: On Sat, Sep 15, 2012 at 1:23 AM, Troy Henderson thend...@gmail.commailto:thend...@gmail.com wrote: and which uses Cairo and Poppler for its conversion. Now in order for my simplistic filter to function, Why 'simplistic' and not 'simple' ? I always thought that its meaning is negative (something like 'simplistic' is a bad imitation of 'simple' ) That's often true. Here I think the intention is to imply that the filter is simple and naive, perhaps not robust, might not work for everybody, etc. In that sense, the meaning does have a negative connotation. This e-mail message (including any attachments) is for the sole use of the intended recipient(s) and may contain confidential and privileged information. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this message (including any attachments) is strictly prohibited. If you have received this message in error, please contact the sender by reply e-mail message and destroy all copies of the original message (including attachments). ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
Whether the filter is simple or simplistic, it is odd that such a filter has not been abundantly available before. I often wondered years ago when I first started to understand the difference between raster and vector graphics why something so simple (or simplistic) could not be easily done. It was also strange to me that I couldn't easily create a TeX document with one set of graphics and have TeX generate two types of output, namely color and a grayscale, depending on the value of some parameters. Utilities are available in abundance which can transform raster graphics from color to grayscale, but until I created this yesterday, I have never seen a utility that keeps the graphic in vector format (i.e., never rasterizes it throughout the conversion) and converts it from color to grayscale. Until I read this thread, I guess I thought I was the only one that desired such a tool. I'm glad to see that at least I'm not alone. Troy ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
Aditya Mahajan adit...@umich.edu wrote: If you want to use eps images, why not just use a white background at ConTeXt end (as you had stated in your first message I think you misread: Pol wants the EPS to be white-on-transparent, instead of black-on-transparent, so that he can use it on a (dark-)coloured background. That is exactly what I wanted. Pol stra wrote: But your answer gave me the idea to use imegemagick, so I found this trick: ... The result is good enough for me. Congratulations. Good luck with your work. Thank you Cheerio, Sietse ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
I tested this on a black-on-transparent EPS that was created via MetaPost, and it seems to work fine. If you are not using Linux (or Unix or Mac OS X), let me know and I can probably put together a quick HTML page to do this on my server. cat foo.eps | sed -e s/0 0 0 setrgbcolor/1 1 1 setrgbcolor/g bar.eps It simply translates the (0,0,0) triplet (which is black) to the (1,1,1) triplet (which is white). This is very simplistic and may not do all that you want. Troy Henderson ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
I put together this little utility for converting a color EPS/PDF/SVG to grayscale. http://www.tlhiv.org/grayscale/ Selecting invert swaps colors from white to black and black to white. So, using a black/white graphic on a transparent background should transform it to a white/black graphic on a transparent background. Testing is certainly necessary. Troy ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
On Fri, 14 Sep 2012, Troy Henderson wrote:
I put together this little utility for converting a color EPS/PDF/SVG to
grayscale.
http://www.tlhiv.org/grayscale/
Selecting invert swaps colors from white to black and black to white.
So, using a black/white graphic on a transparent background should
transform it to a white/black graphic on a transparent background.
Testing is certainly necessary.
Interesting. At some stage I might revive the webfilter branch of the
filler module so that such services can be accessed from within ConTeXt.
See the following post for details:
http://randomdeterminism.wordpress.com/2010/08/12/using-filters-outside-the-box/
In case anyone is interested, this blog post was talking about code
available at
https://raw.github.com/adityam/filter/web/t-filter.tex
https://raw.github.com/adityam/filter/web/t-filter.lua
At some stage I decided to delete these features from the filter module
and move it to a separate module. The code is available at
https://github.com/adityam/context-webfilter
but I haven't used it for about 2 years, and given all the changes in the
internal namespace, I doubt it will run without modifications.
Nonetheless, the idea is that a user can use such services using:
\definewebfilter[grayscaleimage]
[prefix={http://www.tlhiv.org/grayscale},
method=POST,
... some other options
]
and then use
\grayscaleimage{local-image.eps}
This will call the web-service and cache the result.
Aditya
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Re: [NTG-context] Change color of EPS file.
For those that care, here is basically how the service works. The filter is applied to an SVG, and the uploaded graphic is converted to SVG using the following process: EPS - PDF - SVG PDF - SVG SVG - PDF - SVG where the EPS - PDF conversion is done with the standard `epstopdf` included with TeX. The PDF - SVG conversion is done with `pdf2svg` which is available from http://www.cityinthesky.co.uk/opensource/pdf2svg and which uses Cairo and Poppler for its conversion. Now in order for my simplistic filter to function, all SVG's must essentially look alike (i.e., come from the same source). Therefore, uploaded SVG's are converted to PDF (using Inkscape) and then back to SVG (using `pdf2svg`). The filter then works with the resulting SVG and converts it back to the uploaded format using Inkscape. Troy ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
On Sat, Sep 15, 2012 at 1:23 AM, Troy Henderson thend...@gmail.com wrote: and which uses Cairo and Poppler for its conversion. Now in order for my simplistic filter to function, Why 'simplistic' and not 'simple' ? I always thought that its meaning is negative (something like 'simplistic' is a bad imitation of 'simple' ) -- luigi ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
On 12-9-2012 19:10, pol stra wrote: Hello, I have a EPS file wich contains black lines and no background. The background of my presentation is colored, so I would like to put this figure in white. I tried a \startcolor … \stopcolor environement without succed. Is there a way to do so? edit the eps file - Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com | www.pragma-pod.nl - ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
Hello Pol stra, Off-topic for this mailing list, but on-topic for you: You can do this with Inkscape. * Install Inkscape: http://inkscape.org/download/?lang=en * Open the EPS in Inkscape Working white-on-white sucks, so * File Document properties click to the right of 'Background:', below the Default units dropdown * Choose something nice and pastel-coloured with alpha (opacity) set to non-zero. * Select the object * Object Ungroup (Ctrl+Shift+G) to make Inkscape see the individual paths, instead of a single EPS object The single rectangle selecting the object has now turned into a heap of rectangles. * With the colours at the bottom, set the fill to be red with click and/or set the stroke to be red with Shift+click This will probably not have the desired effect because some of the constituent paths will have black fill+transparent stroke, and with others it will be the other way round. So you'll have to set fill/stroke individually. * Select paths in turn, and set their fill/stroke as appropriate. Their respective values are shown in the bottom left. If you select multiple paths and their fill/stroke is different, it will be shown as mixed; when multiple paths' fills/strokes are not mixed they are identical, and you can change them all at once. (Depending on ... file-related things ... you may need to use Path Object to Path at some point, and possibly Path Break Apart. But probably not.) Good luck! --Sietse ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
From: sbbrou...@gmail.com Date: Thu, 13 Sep 2012 13:45:20 +0200 Subject: Re: [NTG-context] Change color of EPS file. To: ntg-context@ntg.nl CC: r...@hotmail.fr Hello Pol stra, Off-topic for this mailing list, but on-topic for you: You can do this with Inkscape. * Install Inkscape: http://inkscape.org/download/?lang=en * Open the EPS in Inkscape Working white-on-white sucks, so * File Document properties click to the right of 'Background:', below the Default units dropdown * Choose something nice and pastel-coloured with alpha (opacity) set to non-zero. * Select the object * Object Ungroup (Ctrl+Shift+G) to make Inkscape see the individual paths, instead of a single EPS object The single rectangle selecting the object has now turned into a heap of rectangles. * With the colours at the bottom, set the fill to be red with click and/or set the stroke to be red with Shift+click This will probably not have the desired effect because some of the constituent paths will have black fill+transparent stroke, and with others it will be the other way round. So you'll have to set fill/stroke individually. * Select paths in turn, and set their fill/stroke as appropriate. Their respective values are shown in the bottom left. If you select multiple paths and their fill/stroke is different, it will be shown as mixed; when multiple paths' fills/strokes are not mixed they are identical, and you can change them all at once. (Depending on ... file-related things ... you may need to use Path Object to Path at some point, and possibly Path Break Apart. But probably not.) Good luck! --Sietse Thanks Sietse I already tried the inskape way, but it’s too much work if you have many files to proced. But your answer gave me the idea to use imegemagick, so I found this trick: convert -background none -density 300 -negate a1.EPS bbb.png I do not know why, but the same command with an EPS output gives me a white background so I had use a png file. The result is good enough for me. Thanks again ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
On Thu, 13 Sep 2012, pol stra wrote: Off-topic for this mailing list, but on-topic for you: You can do this with Inkscape. * Install Inkscape: http://inkscape.org/download/?lang=en * Open the EPS in Inkscape Working white-on-white sucks, so * File Document properties click to the right of 'Background:', below the Default units dropdown * Choose something nice and pastel-coloured with alpha (opacity) set to non-zero. * Select the object * Object Ungroup (Ctrl+Shift+G) to make Inkscape see the individual paths, instead of a single EPS object The single rectangle selecting the object has now turned into a heap of rectangles. * With the colours at the bottom, set the fill to be red with click and/or set the stroke to be red with Shift+click This will probably not have the desired effect because some of the constituent paths will have black fill+transparent stroke, and with others it will be the other way round. So you'll have to set fill/stroke individually. * Select paths in turn, and set their fill/stroke as appropriate. Their respective values are shown in the bottom left. If you select multiple paths and their fill/stroke is different, it will be shown as mixed; when multiple paths' fills/strokes are not mixed they are identical, and you can change them all at once. (Depending on ... file-related things ... you may need to use Path Object to Path at some point, and possibly Path Break Apart. But probably not.) Good luck! --Sietse Thanks Sietse I already tried the inskape way, but it’s too much work if you have many files to proced. But your answer gave me the idea to use imegemagick, so I found this trick: convert -background none -density 300 -negate a1.EPS bbb.png I do not know why, but the same command with an EPS output gives me a white background so I had use a png file. The result is good enough for me. If you want to use eps images, why not just use a white background at ConTeXt end (as you had stated in your first message). Aditya___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
Re: [NTG-context] Change color of EPS file.
Aditya Mahajan adit...@umich.edu wrote: If you want to use eps images, why not just use a white background at ConTeXt end (as you had stated in your first message I think you misread: Pol wants the EPS to be white-on-transparent, instead of black-on-transparent, so that he can use it on a (dark-)coloured background. Pol stra wrote: But your answer gave me the idea to use imegemagick, so I found this trick: ... The result is good enough for me. Congratulations. Good luck with your work. Cheerio, Sietse ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___
[NTG-context] Change color of EPS file.
Hello,
I have a EPS file wich contains black lines and no background.
The background of my presentation is colored, so I would like to put this
figure in white.
I tried a \startcolor … \stopcolor environement without succed.
Is there a way to do so?
In last resort I can put a white background with:
\placefigure[left,none]{caption}{\externalfigure[demo-b][background=color,backgroundcolor=white]}
Best regards
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