Since some years, I have searched for an elegant solution to generate call graphs out of C++ source code. Today I found it. It is doxygen. I have evaluated doxygen years ago, but I threw it away. The reason is that you have to know two things about doxygen:
So, have fun with your call graphs!
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This is the 3rd tutorial in this series, trying to show how effective KDE photography applications can be for fixing and/or improving your photographs overall. In the first and second tutorials we addressed light exposure issues. Ie, we addressed photos that had regions gone too dark or too bright, and we showed how to fix them using either the levels tool or the curves tool.
In this third part we will continue addressing the light issues, but we will target color issues rather than brightness issues.
So lets begin!
Most of the times we use our cameras outdoors. Light is nice, sun shines, and we get nice pictures out of our cameras. But sometimes we need to take pictures indoors, in parties or conferences, and light conditions aren't the best. We even take pictures with flash, sometimes. So what's the problem? - you will ask. Well, many times when taking photos the effect goes unnoticed, but indoor lights are either tungsten lights (yellowish or orangeish) or fluorescent lights (more bluish), and depending on the light conditions, the photo results vary a lot.
Lets see the following example, from Akademy 2008 pictures, kindly donated by Sebastian Kügler for this tutorial:
Yes, it's Mike and Paul, while discussing backwards compatibility issues of core kdelibs changes, in a serious akademy meeting 
Uh, isn't Mike's face a bit reddish? does he actually look like this? is it due to the heated discussion they are having? ... oh wait... no, that's just poor lighting 
So what happenned to that photo. Simply, the room was poorly illuminated by yellowish tungsten lamps, and the camera captured that nicely. Our eyes (or rather, our brain), compensate it automatically to identify the colors, but cameras not always manage doing that.
Most or all digital cameras these days allow correcting that when taking the picture, with an option called "white balance (WB) setting". The menu is usually similar to the following image:
If the camera was set like in this picture (light bulb/tungsten light selected), the picture would have turned out better colored. In the same camera menu, you will find many more options for cloudy/sunny days, fluorescent light, flash light, etc. Please refer to your own camera's manual for more details, since each particular camera is different.
By default, though, cameras are usually preset to AWB (auto white balance). This means that the camera will try guessing which setting of all is the most adequate in each case. It can work nicely, but honestly, most of the times they fail while indoors, like in this case.
So what to do now? Showfoto to the rescue again!!!!!!
Lets open the photo in Showfoto, and select the option Color->White balance... in the menu:
You will get the following dialog popping up:
It sounds complex, right? Well, it's very simple. The most important parts are the top two ones, marked in the image.
Both tools do exactly the same, but the input is a bit different in each case.
The second tool is what you already know. It's equivalent to the camera's White Balance Settings. There's different presets for each light types: 40watt lamps, 100 watt lamps... You can select one of them, and it should fix the colors, but... which of them is the correct one for our light source? hard choice huh?
The first tool is much more flexible. It allows adjusting the Kelvin Temperature of the light. The Kelvin temperature indicates just if the light source was warmer (reddish), or colder (bluish). The more you move the slider to the right, the orange/redder the image will become. The more you move it to the left, the more blueish it will turn. But this tool can be a bit hard to tweak, and usually requires extra hard work like adjusting the green color slider. Not very easy to do.
So what's the solution? It's easy. In the same dialog, right besides the Kelvin temperature setting, you will find a color picker as shown in the next picture. The color picker allows us selecting a point in the original image that should have been white or gray (i.e., not colored, same R=G=B values).
Most pictures have such places. For example, Mike's t-shirt is possibly white around his neck, given the photograph. So I clicked on it:
Impressive, isn't it? Yes, that's the power of white balance correction. Now you really get to see the real colors in the photograph. You can now know that his face isn't orange (), the wall was actually painted yellow, and his t-shirt was dark blue. You can adjust further the tool manually by adjusting the kelvin temperature, brightness of the picture etc (for length reasons, I will leave the exploring of those tools to the reader)
I could just be satisfied with this photo and be done with the tutorial, but I am not. Look at Mike's forehead, the tool has overexposed it and it's all white now. There's no information there, we clipped the histogram. Somehow, for reasons unknown to me, Showfoto's raw tool has a tendency to do this in some photos where highlights exist and have little detail. And no matter how much you tweak the tool you may not get it right, like in this case. But I won't give up.
If you remember from the second tutorial, we learned how to adjust the brightness of the image using curves. Lets do it then. BEFORE applying the white balance tool, lets darken a bit Mike's forehead:
(Notice that moving the right point of the curves tool down is equivalent to using the levels tool, and moving the maximum output level left. Give it a thought )
And now yes, after repeating the same process, I got the forehead not that much overexposed:
In the same tool, I adjusted saturation a bit lower since the shadows were still a bit reddish, and yes. Now just press okay.
Before presenting the image, adjust a bit levels (as shown before in the first tutorial) and we are now done:
Another nice photo and tool for our collection 
Thanks Mike and Paul for this great image and I really hope you enjoy these series. Feel free to give suggestions for improvements and cya in the next tutorial!
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This is the second part of tutorials aimed at showing how to use KDE's photography tools (namely ShowFoto and/or Krita), to process, edit and fix your photographs. The first part of the tutorials showed how to interpret a histogram, and how to use the levels tool. This tutorial will show you how to use a more advanced tool, called the Curves Adjust tool. It's much more powerful than the levels tool but requires more patience and practise to get good results.
So lets begin. This time we have this photo, kindly donated for the tutorial by Jos van den Oever, from his akademy 2008 photos.
The problem in this photo again, is that there are parts of the image that are very dark. The two people are clear in the photo, but the background is so dark that we cannot actually see the pub's details. Let's see what happens if we try using the levels tool, as we learnt in the first tutorial:
As you can see, some parts of the image get blown if we try using the levels tool. What does that mean? It means that we have parts of the image in the right hand of the histogram that have been all converted to white. That's because, unlike the image in the previous tutorial, this image is not concentrated on the left of the histogram. It covers gray levels from black to white. And when we try clipping the histogram with the input sliders, we are "eating" part of those gray levels' information.
Why does this happen? Because the photo scenario had a very High Dynamic Range. Ie, it had objects from very dark (background) to very bright (illuminated by flash).
In this sort of images, if we try moving the input sliders of the levels tool, we will delete part of the photo's gray level information, losing details, and the result isn't nice.
So what to do now? Don't worry, showfoto comes to the rescue again! (#1) We can use the Curves Tool from the menu Colors->Curves Adjust...:
Selecting this option will show a new popup with a dialog that you may find similar to the levels tool. You can see the resulting histogram on top, and the input histogram on the bottom, just like in the levels tool:
The difference is in the way the control works. In this tool, the input histogram has a diagonal line in it. Clicking on it with the left button of the mouse, adds control points. You can move those control points up or down. The result, as shown in the picture above, is that the gray levels from the horizontal axis are converted into the gray levels in the vertical axis.
Moving the control points up, makes that part of the image brighter. Moving them down, makes that part of the image darker.
In this case, I wanted to make the darkest parts of the image brighter, so I added a control point on the left part of the histogram, and moved the point upwards. As the rest of the image was also getting a bit too bright, I added a second control point to avoid it.
So, lets press < OK > and see what we get of it:
We have managed to make the shadows brighter, and now the pub is more visible, but the image is now a bit washed out. As if it were too bright all over the place. Can we do something? Sure, lets try the levels adjustment again:
Now that the shadows were adjusted using the curves, and the colors are more uniform, we can follow the method shown in the first tutorial and adjust the levels of the photo, as shown above. The histogram's main data was a bit displaced to the left, and adjusting levels, I made it cover the whole range again.
Lets see the result:
Ah, now this is much better. The pub background is much more visible and the two persons are not blown.
I think that's already acceptable, but if we are picky, the two people are a bit washed out due to the flash light. So, even if that goes out of the scope of this tutorial (it'll be covered in the following tutorials), lets adjust a bit the saturation in the image for a better result:
Now this image looks much nicer than the original, yes. I hope you liked this tutorial and will see you in the next one!
==========
Notes:
#1: This and previous tools used in the tutorials also exist in krita. We will get to this in the future. For now, I keep using showfoto for being the simplest of the two for using and learning.
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This is possibly one of the most widely used and most simple method to adjust an image. It's so simple and effective that you will want to use it on all your pictures from now on, so keep an eye on this, and have fun.
Lets see this sample photo from Akademy 2008, kindly donated by Sebastian Kügler:
You'll clearly see, the photo is darkish. After all, it was taken during a presentation and possibly the room was pretty dark. But that's no excuse for a bad photo =)
Why is it dark? Lets open the photo in showfoto (digikam's editor) and see what's going on:
On the top right, you can see the image's histogram. (I have pushed the "linear" histogram button to see it more clearly).
So what's the histogram? you'll, ask. The histogram is just a pixel count. It counts how many pixels there are for each gray level, and shows them in a graph. The left part of the histogram are dark/black colors, and the right part of the histogram are brightest colors.
You can see that our image has the histogram concentrated on the left part. Thus, it's mostly black. The right part of the histogram isn't used at all, as shown in the figure. Why did this happen? Just because the camera failed exposing the image properly, or was inappropriately configured.
If a photo is visually pleasing, usually (not always), it covers most of the histogram, from black, to white.
So, is there a way to fix this, then? Of course there is, and it's a very easy one. Select the menu "Color->Levels Adjust":
You will see a new popup showing a tool to adjust the histogram output. There are several parts in it. On the top right, there are two histograms. The first one is the output/new histogram, and the second (bottom) one is the input/original histogram.
As you can see, I have adjusted the output histogram to cover it all, see? So how have I done this. Very simple:
There's 4 sliders in this tool. The first two sliders mark the beginning and end of the part of the histogram that I am interested on. I have moved them to match the full histogram of our original image.
The other two sliders mark the range of the histogram we want as output. We want the histogram to cover from black to white, so just move the sliders to the left corner and to the right corner.
Press "OK", et voilà, your nice photo is fixed. Congrats =)
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Photography has changed a lot since digital cameras broke into our lives and replaced film cameras. Camera makers have made great efforts to convince us that digital is better, and that new digital cameras are worth their money.
Unfortunately, this isn't completely true. Being so cheap, people shoot thousands of photos a day, careless of their quality. why care? they just want to capture something for their memories. The answer is: check your memories of akademy 2008. Do you actually remember your friends there as being greenish and pale? Well, that's what some of the photos looked like =)
So, after looking at the quality of pictures taken by people in Akademy 2008, and thanks to the suggestions of a few devels, I thought of writing a series of tutorials on how to fix your green friends... errrm... I mean your photos using KDE
So lets begin! KDE comes to the rescue!
In the following posts I aim at writing down some basic tutorials on how to fix your photos using KDE tools. I will be using tools available to everyone, including showfoto and krita possibly, and could be gimp too. It's not meant to be exhaustive, since that would take writing a whole book, but it will cover the most annoying and basic fixes that will get you started.
Using this post, I'd like to request kde fellows permission to use some of their akademy pics to write this series of tutorials. .
Anyway, good luck with your new photos!
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We now have documentation for our custom KDE CMake Modules, brought to you by the EBN. I have a little script that runs every night to re-generate this page, just in case we changes things as time goes by.
But, if you're like me, you'd rather have quick access to a man page. You can create one with the following command:
% cmake -DCMAKE_MODULE_PATH=/path/to/kdesvn/trunk/KDE/kdelibs/cmake/modules --help-custom-modules /path/to/kdeinstall/share/man/man1/kdecmake.1
making sure that /path/to/kdeinstall/share/man is in your $MANPATH, of course.
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Too many KDE folks refuse to use http://techbase.kde.org/ because it breaks blocks of code.
You can however make it usable. A hint just for you:
[jstaniek] btw, I've improved http://techbase.kde.org/Projects/PIM a bit, and have 'windows port' column
[jstaniek] does not use oxygen wiki style which actually causes usability problems with blocks
[marc_kdab] oh, you can switch the style?
[marc_kdab] how?
[marc_kdab] that could actually make the wiki readable 
[marc_kdab] hates fixed-width formats in websites
[jstaniek] marc_kdab: ah, so I should blog about this; too many folks complain... and I talked to danimo @ akademy but... well...
[jstaniek] (same for websvn, btw)
[marc_kdab] yes, and the apidox
[jstaniek] marc_kdab: login -> my preferences (on the topbar) -> skin tab -> monobook
[marc_kdab] oh, sigh, login...
[jstaniek] marc_kdab: y, you can set permanent login
[jstaniek] hacked his wiki page with readable breadcrumbs, eg. "News->Kexi Releases-> Kexi 2007.1" and forced reasonable width (http://kexi.pl/en/News/Kexi_Releases/Kexi_2007.1)
[marc_kdab] ahhh
[marc_kdab] mediawiki look
[marc_kdab] files a request for mediawiki to remove styling
[jstaniek] the oxygen style is great but also breaks mediawiki skin rules a bit - e.g. we have even no kde logo defined for the web site...
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What a coincidence today happened. In the morning I used KDEPrint's 'poster' frontend to create a "poor man's poster" in A1 size from 4 A3 printouts.
In the afternoon, a lady mailed me, asking why her KDE print dialog on Solaris didn't show the poster dialog, while her husband's openSUSE KDE did show it.
I took the time, mailed her back what I knew about the question, and included a few screenshots.
Two hours later I thought for myself: "WTF -- you took more than half an hour to write back to this lady and explain everything to her... Why not put another 30 minutes effort into it and convert the mail into a little tutorial to be published in my blog?".
I slightly changed my earlier mail in a few sentences, re-arranged it a bit, and posted a screenshot with a long comment to kdedevelopers.org.
Hardly I was ready with this when I saw a posting by Hin-Tak on the 'printing summit' mailing list over at linux-foundation.com, asking about ... poster again (without remembering the name of the utilitiy). Happily I mailed the link to said image with comments back to him.
And now it's "Heck! I may as well make a real blog post from it, add a few more screenshots and declare it a tutorial...."
So here we go.
You 
may already have come across the "Poster" tab in KDE's printing dialog. The one the screenshot to the left shows. It should be there for each printer you select from the drop-down list, even the virtual ones, that "Print to File" or "Send to Fax" or "Mail PDF File".
However, the poster tab of kprinter will *NOT* show up if you don't have the "poster" utility installed and in your $PATH. So if you want it, simply install the 'poster' package.
Obtain "poster" from here: printing.kde.org/downloads/.
Important: you need to use the version from the link above, should your distro's version not function properly! It contains some patches to make it work with KDEPrint (poster's commandline abilities don't suffer from these patches!). The patches (written by our deerly missed Michael Goffioul, who currently does have too little time for active KDEPrint development) have also been accepted by the upstream poster developer, years ago.
Unfortunately, some recent distro releases (Debian?, *buntu?) for some reason seem to ship an older version which makes the kprinter poster tab display an error message.
As soon as you install the patched version (compiling it is easy), kprinter will start work with it.
If you figure your distro is using a b0rken version (or no poster package at all), you should contact its respective packager and/or submit a bug report or feature request. Ask them to use the patched version of poster to make it work with KDEPrint.
Poster is meant to scale up a printout beyond available media sizes of your printer. You print 
small tiles 
of the final image 
on your available paper (you do not even need to print all of them, as the line "tiles to be printed" shows). These pages you can glue together to form a "poor man's poster".
The actual printouts will slightly overlap, in order to allow some minor image shifting by the actual print devices, and by the person who uses scissors or cutters to trim the paper sheet towards the actual page image.
- Above screenshot shows what you can tweak with the settings (click thumbnails full size).
- Determine the final poster size by selecting from the drop down listbox.
- Determine the size of the printouts as "Page Size" on the "General" tab.
- The number of tiles shown dynamically adapts to these size selections.
- To select which tiles you want at all use the mouse and hold the shift key.
- Printout will occur in the order you clicked the tiles (or typed their number into the line edit).
- Alternatively, just type a comma-separted list of tile numbers into the line edit field.
- Change the "Cut Margin" as needed.
What benefit is it to make it selectable which tiles print, not not do all at once?
Well, you may want to try with two tiles first, and see if they fit and match what you expect. If they do, continue with more tiles, different ones this time. If they don't, change you settings and try again.
Tip 1: do not waste too much paper with experiments whose results you will not like. Instead you may first want to "Print to File (PDF)" by selecting such a printer in the first place.
Or enable the checkbox "Preview" on the main kprinter dialog, and cancel the printout if the preview doesn't look like you expect; then try again with different settings.
How it works "under the hood": poster is utilized as a "prefilter" by KDEPrint. When KDEPrint receives a PostScript for printing (as is the case when you print from any KDE3 application), it sends this file to poster first, using appropriate commandline options (which you do not need to know if you use the GUI shown in the screenshot -- they are a bit awkward), receives the pre-filtered file from poster and sends it on to the real print subsystem (or to the preview application you may be using).
Of course, poster (the utility) isn't perfect, and if it fails, KDEPrint can't do much about it....
What you can do when it doesn't seem to work at all...
The utility and the kprinter tab do also work if you start kprinter as a standalone application (i.e. not from the 'Print...' menu entry of an application) and load a PostScript file into it.
However, 
if you start 
kprinter standalone, 
but load a non-PostScript file (text, image, PDF), and use "poster" on it, you may see an error message, or it may simply not work as expected. If you are lucky, you'll see a dialog pop up that asks if KDE should convert the original file for you to create the correct format.
Why is this?
The poster utility can only work with PostScript files and does require PostScript as input format. (To be more precise: it expects a PostScript file that follows the DSC recommendations, the Document Structuring Conventions for PostScript files).
Is there no hope then?
Yes, there is.
Stacking different pre-filters...
Just plug one more pre-filter into the pre-filtering chain of KDEPrint! One that creates the PostScript and feeds it to 'poster'. 
How to do that?
Click on the right-most tab, labelled "Filters". Click on the top icon showing a funnel symbol. Select a pre-filter from the top-down list that takes your loaded input format, and converts it into PostScript:
- "Generic Image to PS Filter",
- "PDF to PostScript Converter", or
- "Enscript Text Filter"
Make sure the stacking order of the two pre-filters (the "Poster" one may be active already)
is as needed. (If it's wrong, you'll see a unequivocal complaint in the user interface -- you can sort the order with the help of the "Up" and "Down" arrows.)
Tip 2: The "Preview" checkbox is not available, if you run kprinter from the commandline. If you are not confident about the results that will go on paper, and if you don't want to waste precious resources, you may want to "Print to File" first instead of the real printer. Then you can verify if the result comes at least close to what you expect by using KPDF to view it (KPDF also works with PostScript files, should you have printed to PS).
Tip 3: While the "Preview" checkbox is not there, another one is, when you run kprinter from the commandline: it is on the bottom left corner of the dialog, labled "Keep this dialog open after printing", and does what it says. So as long as you are experimenting with the different print settings, you do not need to restart kprinter every time you want to change an option....
Voila! Poster printing with KDE.
From any KDE application.
With preview of results.
To any print device.
Even to the "PDF printer" that ships with KDE.
And also for any printable file format (PDF, image, PostScript, text),...
...when loaded into a kprinter started from the commandline (remember to enable an additional prefilter; one that consumes your original file, produces PostScript and pipes its output into the Poster pre-filter...)
How do you like that?
(And all this works in KDE since the days of KDE 2.2, released more than 6 years ago. But unfortunately, it was never really documented, remains a rather unknown little gem within KDEPrint, and in general is pretty under-appreciated.)
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What a coincidence today happened. In the morning I used KDEPrint's 'poster' frontend to create a "poor man's poster" in A1 size from 4 A3 printouts.
In the afternoon, a lady mailed me, asking why her KDE print dialog on Solaris didn't show the poster dialog, while her husband's openSUSE KDE did show it.
I took the time, mailed her back what I knew about the question, and included a few screenshots.
Two hours later I thought for myself: "WTF -- you took more than half an hour to write back to this lady and explain everything to her... Why not put another 30 minutes effort into it and convert the mail into a little tutorial to be published in my blog?".
I slightly changed my earlier mail in a few sentences, re-arranged it a bit, and posted a screenshot with a long comment to kdedevelopers.org.
Hardly I was ready with this when I saw a posting by Hin-Tak on the 'printing summit' mailing list over at linux-foundation.com, asking about ... poster again (without remembering the name of the utilitiy). Happily I mailed the link to said image with comments back to him.
And now it's "Heck! I may as well make a real blog post from it, add a few more screenshots and declare it a tutorial...."
So here we go.
You may already have come across the "Poster" tab in KDE's printing dialog. The one the screenshot to the left shows. It should be there for each printer you select from the drop-down list, even the virtual ones, that "Print to File" or "Send to Fax" or "Mail PDF File".
However, the poster tab of kprinter will *NOT* show up if you don't have the "poster" utility installed and in your $PATH. So if you want it, simply install the 'poster' package.
(UPDATE: Seems after Michael Goffioul's patches from 2002 there were more new features added to poster (which I wasn't aware of). There's a bug report 132916 which was pointed out to me in a comment below by jlp. Given that the bug reporter says "version 20060221 doesn't work, while version 20050907 does", it is probably saver to download and use the latter. BTW, openSUSE ships the version 20020826 which works as well. This bug may explain why Gentoo and Debian have reverted to a 1999 version of poster, which does not work with KDEPrint.)
Obtain "poster" from here: ftp.kde.org/pub/kde/printing/.
Important: you need to use the version from the link above, should your distro's version not function properly! It contains some patches to make it work with KDEPrint (poster's commandline abilities don't suffer from these patches!). The patches (written by our deerly missed Michael Goffioul, who currently does have too little time for active KDEPrint development) have also been accepted by the upstream poster developer, years ago.
Unfortunately, some recent distro releases (Debian?, *buntu?) for some reason seem to ship an older version which makes the kprinter poster tab display an error message.
As soon as you install the patched version (compiling it is easy), kprinter will start work with it.
If you figure your distro is using a b0rken version (or no poster package at all), you should contact its respective packager and/or submit a bug report or feature request. Ask them to use the patched version of poster to make it work with KDEPrint.
Poster is meant to scale up a printout beyond available media sizes of your printer. You print small tiles of the final image on your available paper (you do not even need to print all of them, as the line "tiles to be printed" shows). These pages you can glue together to form a "poor man's poster".
The actual printouts will slightly overlap, in order to allow some minor image shifting by the actual print devices, and by the person who uses scissors or cutters to trim the paper sheet towards the actual page image.
- Above screenshot shows what you can tweak with the settings (click thumbnails full size).
- Determine the final poster size by selecting from the drop down listbox.
- Determine the size of the printouts as "Page Size" on the "General" tab.
- The number of tiles shown dynamically adapts to these size selections.
- To select which tiles you want at all use the mouse and hold the shift key.
- Printout will occur in the order you clicked the tiles (or typed their number into the line edit).
- Alternatively, just type a comma-separted list of tile numbers into the line edit field.
- Change the "Cut Margin" as needed.
What benefit is it to make it selectable which tiles print, not not do all at once?
Well, you may want to try with two tiles first, and see if they fit and match what you expect. If they do, continue with more tiles, different ones this time. If they don't, change you settings and try again.
Tip 1: do not waste too much paper with experiments whose results you will not like. Instead you may first want to "Print to File (PDF)" by selecting such a printer in the first place.
Or enable the checkbox "Preview" on the main kprinter dialog, and cancel the printout if the preview doesn't look like you expect; then try again with different settings.
How it works "under the hood": poster is utilized as a "prefilter" by KDEPrint. When KDEPrint receives a PostScript for printing (as is the case when you print from any KDE3 application), it sends this file to poster first, using appropriate commandline options (which you do not need to know if you use the GUI shown in the screenshot -- they are a bit awkward), receives the pre-filtered file from poster and sends it on to the real print subsystem (or to the preview application you may be using).
Of course, poster (the utility) isn't perfect, and if it fails, KDEPrint can't do much about it....
What you can do when it doesn't seem to work at all...
The utility and the kprinter tab do also work if you start kprinter as a standalone application (i.e. not from the 'Print...' menu entry of an application) and load a PostScript file into it.
However, if you start kprinter standalone, but load a non-PostScript file (text, image, PDF), and use "poster" on it, you may see an error message, or it may simply not work as expected. If you are lucky, you'll see a dialog pop up that asks if KDE should convert the original file for you to create the correct format.
Why is this?
The poster utility can only work with PostScript files and does require PostScript as input format. (To be more precise: it expects a PostScript file that follows the DSC recommendations, the Document Structuring Conventions for PostScript files).
Is there no hope then?
Yes, there is.
Stacking different pre-filters...
Just plug one more pre-filter into the pre-filtering chain of KDEPrint! One that creates the PostScript and feeds it to 'poster'.
How to do that?
Click on the right-most tab, labelled "Filters". Click on the top icon showing a funnel symbol. Select a pre-filter from the top-down list that takes your loaded input format, and converts it into PostScript:
- "Generic Image to PS Filter",
- "PDF to PostScript Converter", or
- "Enscript Text Filter"
Make sure the stacking order of the two pre-filters (the "Poster" one may be active already)
is as needed. (If it's wrong, you'll see a unequivocal complaint in the user interface -- you can sort the order with the help of the "Up" and "Down" arrows.)
Tip 2: The "Preview" checkbox is not available, if you run kprinter from the commandline. If you are not confident about the results that will go on paper, and if you don't want to waste precious resources, you may want to "Print to File" first instead of the real printer. Then you can verify if the result comes at least close to what you expect by using KPDF to view it (KPDF also works with PostScript files, should you have printed to PS).
Tip 3: While the "Preview" checkbox is not there, another one is, when you run kprinter from the commandline: it is on the bottom left corner of the dialog, labled "Keep this dialog open after printing", and does what it says. So as long as you are experimenting with the different print settings, you do not need to restart kprinter every time you want to change an option....
Voila! Poster printing with KDE.
From any KDE application.
With preview of results.
To any print device.
Even to the "PDF printer" that ships with KDE.
And also for any printable file format (PDF, image, PostScript, text),...
...when loaded into a kprinter started from the commandline (remember to enable an additional prefilter; one that consumes your original file, produces PostScript and pipes its output into the Poster pre-filter...)
How do you like that?
(And all this works in KDE since the days of KDE 2.2, released more than 6 years ago. But unfortunately, it was never really documented, remains a rather unknown little gem within KDEPrint, and in general is pretty under-appreciated.)
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