Recently I played with raytracing and POV-Ray for artificial landscapes generation. My goal was to have the realistic “Google Maps-style” images of the Middle-earth terrains to create the maps for Tolkien Gateway Encyclopedia – the wiki project I’m involved in. You can see my first outcome here. This is a reduced snapshot of rendering the whole scene.

Technology

I used POV-Ray for Linux raytracing engine and povray scripts from Geomorph tool. For my purposes I had to hack the scripts (sea_and_rocks.pov and basic geomorph_txtr.inc) and tweak them a damn lot of time until I got what I expected to see. It was especially tricky task for me, as I am definitely not an expert in POV-Ray language (what is more, except for few dummy excercises it was my first serious POV-Ray scripting experience).

A source of the relief information is so-called “height map” – a monochrome bitmap where the values of pixels are translated into the heights of the terrain points. It was drawn manually in GIMP on few semi-transparent layers above the scanned real Middle-earth map from “The Lord of the Rings” (the famous Christopher’s map which is admitted as the most authentic one). The layers then were merged together (except for original map, of course) and saved as PNG for using as the height-map. It was also a tricky and lengthy process – as it was non-interactive, I might see the result of changes only after re-saving and re-rendering and it took a lot of time, especially at final polishing stage.

When I went through all it, I finally got a 3D landscape scene which now can be rendered from various point of views to get the base terrains for the maps of Middle-earth regions. Huh.

It looks like Google decided to simplify things as much as possible. They just took the original Picasa for Windows and made it working on Linux with Wine (it is included into the Picasa Linux distribution). So, it is really not a true Linux version. But due to stability of Wine technology (see my “Wine and Photoshop” post) it seems to work well.

At first view, Picasa provides the same set of the photo organizing functionality as digiKam. It supports the same faceted photo collections organized by folders, timeline and tags (“labels”). The only difference is a distinctive feature of any Google product – the search box which is always presented in the program window. The photo editing functionality is also similar to the default set of digiKam tools. But the rich set of digiKam’s additional plugins makes it image processing functionality looks more professional, while Picasa supports only a basic set of simple and most needed image fixes and effects. Many of them are automated and lack some fine-tuning but in general, they should be suitable for the most of non-professional photographers.

And, as it was expected, Picasa doesn’t import photos to Flickr – perhaps by understandable (competition) reasons.

This poster is designed using Adobe Photoshop 7.0 run on Linux operating system with Wine technology. The wine in the glass is real and had been used for its purpose after photosession.

© 2006, me
If you are a Wine project member, you are welcome to use this poster but let me know, please.

Why not to try to run Photoshop under Wine? – I thought. I should say, I never had used Wine technology before. I had some biases against it and for years of using open source I missed no Windows apps. But it seemed it was just the case.

The biggest of my biases against Wine was it should be a huge and very complex thing – it looked like I had to move perhaps a half of the whole Windows to my box and setup it for weeks to get it working. I was absolutely wrong! Installing Wine on my Fedora IV is turned out to be simple as installing a single RPM package and needed no configuring. Then I mounted Photoshop 7.0 CD, run “wine Setup.exe” and voila! – I got Photoshop installed on my Linux system.

I didn’t test it alot but so far it seems to work pretty well. It’s fast enough (my another bias on Wine was that it should be painfully slow) and all Photoshop functions are workable. I can create, open, edit and save PSD files without any problem, can work with layers, effects, text and so on. It correctly recognized all TTF fonts installed in X and my default CUPS printer. So far, I only noticed some minor visual glitches with “palettes” (maybe because they utilize a non-standard API) and that it doesn’t work with KDE clipboard (though, it was predictable).

© me 2000

For years I used no special software for digital photography and photoalbums management. Just command-line gphoto2, GIMP and usual filemanager in preview mode were enough, or at least I thought so. Few months ago I decided to scan my old photo archives to have them in digital form and was drowned quickly in the thousands of shots many of which needed for some correction. And new shots from my digital camera are going on. So, once I felt I’ve lost control on my photo collection.

I looked for a software which could help me and found digiKam – a great photo organizer, editor and more.

Acquiring photos

digiKam works directly with a digital camera. In fact, it depends on gPhoto framework, so you need to have gphoto2 installed and working (if you are a photographer on Linux, you probably already have it). digiKam provides an easy to use interface to the camera that enables you to browse, preview, download and delete your images.

Camera interface

For those who used to download photos with gphoto2 from console, this new experience is really impressive.

digiKam also can acquire images directly from a scanner (through SANE interface) and grab the screenshots. Of course, you can also import your existing photo directories into the digiKam database.

Organizing

An essential part of digiKam what makes it a really great app is its photo organizing functionality. It makes use of a database to store tags, comments and other metadata related to images and albums. So, you can easily find, browse and sort images in your collection.

The photo browser supports faceted navigation – you can explore your collection by albums (just the folders), tags or dates. It is possible to assign a number of tags for each photo which makes its finding extremely easy (if you are a Flickr user, you know what help the tags make).

    
Faceted navigation by tags and dates

[added]
The key difference from the Flickr tags (not too obvious) is that the tags can be organized hierarchically – they are rather taxonomical categories than usual labels. So you can set, say the “Roses” tag as a child of “Flowers”, and “Flowers” in turn, as a child of “Nature”. Then, all your “Roses” photos will automatically be assigned to “Flowers” and “Nature” which makes a great help in further navigation

The advanced search functionality enables to select the shots which match the specific criteria (it looks like the queries to database). You can save your queries to quickly repeat them in future.

There is a bit of fantastics – searching images by similarity. It makes use of an intellectual algorithm of “fingerprints” to compare images and find their “optical similarities”. You can adjust a treshold level to find more or less similar images – from the exact duplicates to the “slightly resembling” shots (for instance, from the same session).

It supposes these shots are similar. I think so too :-)

Editing: Goodbye, GIMP?

digiKam integrates an advanced image viewer/editor (ShowFoto) which also can be used as a standalone application. Along with basic image processing functionality (cropping, resizing, rotating, color correction) it supports a plugins architecture for to add new tools and image effects. digiKam plugins are developed by another project and should be downloaded and installed separately. Current distribution includes a variety (about 30) of plugins including correction filters, funny artistic and distortion effects, adding borders and text to images and so on.

The most interesting and useful tools for photographers are, of course, those for improving image quality. digiKam provides a rich set of those tools (both embedded and pluggable) – from basic brightness/contrast/color adjustments to sophisticated photo restoration utilities. They are collected in a “Fix” menu of the image editor:

I think, even a professional photographer will be happy with that toolkit. All filters have the live previews and work surprisingly quickly. In general, digiKam seems to work much more faster in comparison with monsters like GIMP or Photoshop.

There is a magic feature which really impressed me – an “auto-correction”. It is unbelievable, but by a single mouse click you can turn your ugly dark or low-contrast photo into an eye-candy. Just take a look:

Auto-correction: before and after

digiKam makes use of the KIPI plugin framework which aimed to be a common shared plugin infrastructure for KDE graphic apps. The current set of KIPI plugins enables very useful features of batch image processing. You can do resizing, converting, adjustment, applying filters and effects on the selected photos or even on the whole directories just by few mouse clicks.

Sharing and exporting

Yes, digiKam does flickring! Uploading photos to there is a snap – just choose images you want to upload and (optionally) enter the Flickr tags and privacy options. At very first time it will open your default browser for logging in to Flickr. A very useful feature is that it can resize the uploading shots on the fly, so you don’t need to prepare the special low-res variants of your original shots. For instance, I usually take the hi-res shots of 1600×1200 or even more, and reduce them for Flickr to 640×480, so automatical scaling makes a great help for me.

digiKam also can build HTML photo galleries, burn CD/DVD with your photo collections (via external b3d software) and of course, print your photos.

A really cool and handy app which seems to have no competitors in Linux world for now. Recommended for all Linux photographers – profies and amateurs like me.