10 April 2014

A license to print money

We learned (link in Romanian) the Romanian government is negotiating with Microsoft for a Windows XP support extension in the public administration. This is the free market at work and there may be solid arguments for doing so (yes, I would prefer my tax money to be spent on Free and Open Source Software instead of making business with a convicted monopolist, but realistically I don't expect this to happen in the foreseeable future).
My source of amazement is: once the patches and the delivery infrastructure are set for the first government (UK), then the costs for adding any subsequent government is approaching zero: computers in Romanian administration usually have Windows installed in English, so there is nothing to translate, the infrastructure to deliver patches is there and the network costs are the same or lower (presumably patches fro XP are smaller in size as patches for Windows 7).
Apparently ending support for XP makes a lot of business sense for Microsoft, they suddenly started receiving important sums of money for things they did only a week ago for free. Who would refuse that?

08 April 2014

On the Mozilla scandal

Like many of you, I too received the Mozilla email about "helping" with communications regarding the "activities of the past week", which is an euphemism for the Brendan Eich scandal. It comes with a FAQ you are expected to quote when talking about the issue.

Since all communications from Mozilla on the topic were opaque, either in blog posts with comments disabled or emails from generic addresses where is useless to reply, I finally decided to write something. Anyway, April 1-st, when I learned about the topic, wasn't a good day to write about serious issues. It may be not me my business what happens inside the Mozilla corporation, but if the Mozilla community feels a need to guide my public communications about it, then maybe it is.

So I am totally unhappy with Mozilla to caving-in to pressure from bullies. It creates a serious precedent and a slippery slope. What's the next step? Once a new CEO is announced, no matter who he is, the browser will be blocked by anti-gay websites? It looks like we are going towards a Balkanized web, where the "best viewed with [Internet Explorer|Netscape Navigator]" buttons are replaced by "blocked for browsers whose CEO have private opinion X".

Seriously, instead of personal political opinions of the Mozilla CEO I was more concerned about him wasting resources on the mobile OS unicorn while the browser looks more and more like a Chrome copy-cat.

18 March 2014

DPI and photography

There is a good understanding of DPI among hardware geeks (they may boast about how superior is tablet X due to a higher DPI display), still I am surprised to see how many people from the photography world do not understand this (sometime don't want to learn, on the "is technical stuff, I am an artist and not care about technical details") to the point it becomes ridiculous, so I will try to explain it with simple words, in case someone will pay attention.

DPI stands for "Dots Per Inch" and is a characteristic of a hardware device (for example a computer/tablet/phone display). It says how many pixels are in one inch (1 inch = 2.54 cm). Example: the computer I use to write this piece has a 38 cm wide display, which is 38 cm / 2.54 ~= 15 inches. Considering the horizontal resolution is 1600 pixels, then it has a resolution of 1600 pixels / 15 = 106.67 DPI. Of course, the higher the DPI value, the better looking the image will be on your display, as it will enable to to see finer details.

dpi screen
In digital photography the situation is different: your photo is a file and it can be put on a wide range of displays. The DPI value is not as important as the actual image resolution in pixels, it is actually metadata. Actually the correct term when talking about photos is PPI, standing for "Points Per Inch", but PPI and DPI are close enough, is not a huge problem if you interchange them. PPI is relevant when you print the image, is the density of color points to be printed by a inch. The math is similar and having a target print size and print image quality (PPI), it will help determine the needed pixel resolution. Example: you want to print a 15 x 10 cm image at good quality (300 PPI). On the horizontal 15 cm / 2.54 = 5.9 inch, then 5.9 inch * 300 PPI = 1770 pixels. On the vertical, 10 cm / 2.54 = 3.96 inch, then 3.95 inch * 300 PPI = 1182 pixels. In conclusion, you will need a 1770 x 1182 pixels image. 1800 x 1200 is close enough and easy to remember, so a 1800 x 1200 image will print at good quality at 15 x 10 cm.
dpi print
JPEG is the file format we use day to day to exchange photos and it has the ability to store a DPI value somewhere inside its metadata, but is only metadata: an indication at which size (in cm or inches) to print the file. But you can print the same file at any dimension or any DPI/PPI value (of course, with the respective image quality consequence). Changing this value won't modify in any way the look and work of your digital file.

Now, what is a good DPI value for your print? This depends on its intended use, of course :) A 300 DPI is considered good enough for a quality print, like those in the glossy magazines, where you look closely and expect to see fine details. When printing a poster which will be seen from a couple of meters, you can lower the DPI value at 100 and for a billboard to be seen from tens of meters, you can go way lower: it does not mater the printed points are huge when looking closely, nobody will do that.

Now another practical example to illustrate the ridiculous part and how to deal with it. For a recent photo exhibition (it is still on display), the requirements were "100x66 cm at 240 DPI". This is ridiculous: 100 cm / 2.54 = 39.4 inch, 39.4 inch * 240 DPI = 9456 pixels and 66 cm / 2.54 = 26 inch, 26 inch * 240 DPI = 6240 pixels, so to satisfy it you need a 9456 x 6240 photo, which means 9456 * 6240 = 59005440 - you need a 60 Megapixel camera to produce it. Nobody in the target group for that expo has access to such a camera. What to do?

Knowing the people, I can safely say most of them just ignored a requirement they don't understand, and even if they understand can't follow. Still, some tried their best and this is the right thing to do, consider other exhibitions have sane requirements you can, and then should, follow, like the one asking for 1400 x 933 at 96 DPI.

The most obvious thing to do is to resize your image to achieve the needed resolution in both pixels and DPI (GIMP example below). This is sensible thing to do when you scale down the image, as in the 15 x 10 cm case, (reduce the pixel resolution count) and you can optimize interpolation method and post process your image. However, when it would need to scale up, as in the 100 x 66 cm case, is not only a waste of resources and time, extrapolation will lower the image quality so the result will be worse than printed at a low DPI value.
dpi print
What I do in such cases (and I got my images accepted in quite a few exhibitions) is to give the image at the largest pixel resolution I have available and then set the metadata DPI value for the desired target in centimeters, even if lower than the requirement. Is going to be the best print I can anyway.
dpi print
Most of the photos you will encounter have a value of 72 DPI, this is because that is the value assigned by default by the camera for historical reasons: it was the common resolution for computer displays when digital cameras were introduced to the market, at the time we used 14"-15" CRT monitors. I am not sure I can change it inside my Canon, but it does not matter: most of my photos are to be shown on a computer display and I can change the value (as shown above) when editing for a special print.

Of course, as I told above is specific to photography. For illustration/vector graphics is a different matter, we may talk about at another time if there will be enough interest.

27 January 2014

Nightmare wallpapers

A fan of my photos keep asking for large resolution versions of various pics (I usually put online web-optimized stuff) so I cave in, that's the explanation for me having often posts like this.
The images below are pretty-much made in camera (they were edited with GIMP only for crop, resize, BW conversion and color curves adjustment). The motion blur is created in-camera, with the following recipe (which you can learn looking at EXIF data): put a somewhat long exposure time, 1/10-1/15 of a second, start moving the camera and then press the shutter. The first and the last are made moving the camera on the vertical axis and the second by rotating the camera and zooming at the same time - pretty easy but you will need a bit of exercise to achieve a smooth movement.

nightmare wallpaper
nightmare wallpaper
nightmare wallpaper

22 January 2014

MP4 and Wikipedia

Last week when I read about the request for comments on Wikimedia supporting MP4 video I wasn't at my computer, so I couldn't vote and later forgot about it. My position here is simple: supporting proprietary and encumbered formats can only harm the open web, so Wikipedia and all the other Wikimedia websites endorsing it would be a huge blow for the openness and community, so I strongly oppose. However, I acknowledge a lot of the existing devices produce content in such formats, so I guess a reasonable compromise would be allowing such uploads but then transcode the videos in open formats and serve those for viewing.

Today I was reminded about the issue by a message on some Wikimedia mailing list by a message worded in such way, I can easily label as "pro MP4 spam". It was a good incentive for me to finally answer the RFC/vote.

Still, I am disturbed to see a "product manager" at Wikimedia Foundation campaigning for MP4, especially when the public opinion is strong against it (at this moment it records 251 votes for no support, votes for contributing only, no view and only 132 for full support, so more than 2:1).

08 January 2014

On Red Hat and CentOS joining forces

Red Hat and CentOS joining forces is a really smart move and it potentially is a win-win scenario for all parties involved: Red Hat, CentOS, community, end-users, FOSS. I won't enter into details, since a lot of people are talking about this already.

However, what baffles me is how little people understand the reasoning. So many comments frame it in the old context: a lot of projects need a no-cost Linux solution, and if they can't use a Red Hat derivative, they will use a Debian flavour and later when money will get involved, they will buy support from Canonical instead of Red Hat. Yes, this is a solid reason, but is the old reason. What we see now is something else.

The real reason for Red Hat embracing CentOS now is written plainly everywhere, from the press release "Red Hat is once again extending its leadership in open source innovation by helping to establish a platform well-suited to the needs of open source developers that integrate technologies in and around the operating system" to the FAQ "Red Hat is taking an active role in the CentOS Project to accelerate the development and broaden the reach of projects such as OpenStack by expanding our base."

These days Red Hat is selling not only the established Red Hat Enterprise Linux, but quoting from the same press release, things like "OpenStack, RDO, Gluster, OpenShift Origin, and oVirt" solutions. Compared with Linux, those technologies have so far less traction but comparable potential. Having CentOS as a strong player and supporting all those technologies will make them more popular and increase the chances for a later sale of more than RHEL.

Everything mentioned above is Free Software, so it can be a win-win for all of us. Of course, there are dangers (GNOME 3, I'm looking at you!) but there are safeguars: if the srpms will be easier to get, projects like Scientific Linux will have the life easier too.

02 January 2014

Night wallpapers

For the New Year night I chased some fireworks pictures, but in the wrong place (had to stay near home) so the result was not spectacular (I didn't have high expectations for the fire show in the nearby park). But having the gear with me and noticing the park at night, which do looks different, I turned on them for more pics, which were then posted in the usual places. Receiving a specific request on some social network for high resolution, I follow with a blog post with wallpaper sized versions:

night wallpaper
night wallpaper
night wallpaper
night wallpaper

29 December 2013

Anaglyph

Disclaimer: to properly read the following article, you need to have a pair of red-cyan 3D glasses, otherwise the images won't display as intended. The cheapest one should do it, perhaps even home made. Lacking such glasses, you can generate your own 3D images for different types of glasses.

A few weeks ago I stumbled upon an old article about how James Cameron is/was remaking Titanic in 3D and somewhere in the technical explanation it was mentioned you can do 2D to 3D conversion with Free Software tools, namely the G'MIC plugin for GIMP.

In the late '90ies I received a computer magazine which came with a pair of paper 3D glasses and a CD containing the usual software demos AND a few 3D pictures, it was my first contact with anaglyphs. I still have the glasses, but I use them maybe once every few years, when I remember to search some such images.

Along the time I learned how to properly make such images: two cameras, filters, combine the two images in one. Way too much effort for me. It looks like way too much effort even for some commercial filmmakers...

When I saw the Titanic article, I said to myself 'what the heck, let give G'MIC a try'. AFAIK it is not available in any official Fedora repo, but you can download a binary from the upstream, drop it in the proper folder and go with it. It will survive even a distro update/reinstall. Not a big fan of the 'application inside another application' approach of G'MIC, nor of its duplication of existing GIMP features, that's why didn't have it already installed, but playing is fun.

anaglyph

I don't have the time and patience to learn how to fine-tune the parameters (with hand crafted depth maps you should be able to reach high quality results), nor do I plan to return to anaglyphs any time soon, so I used pretty much the automatic settings. Below are a few pictures I think came decently with no fiddling and automatic settings:
anaglyph

anaglyph

anaglyph

anaglyph

anaglyph

anaglyph

anaglyph

22 November 2013

Mist wallpapers

When I took pictures of the overwhelming mist, it became obvious such minimalist image have a great potential for effective wallpapers: they are simple and won't stand on your way. So here are some for anyone want to use them. Enjoy and don't let their mod depress you :)

mist wallpaper
mist wallpaper
mist wallpaper
mist wallpaper
mist wallpaper
mist wallpaper
mist wallpaper

15 November 2013

Programatica

At first, I received the invitation for the Programatica - Open Source conference for the Fedora community, but since I don't have much to say on this matter, I passed it (I am a Linux desktop user these days and Fedora does not shine there). When the invitation arrived at ProLinux and was difficult to find a speaker, I offered myself for the task.

The conference was mixed, it had 3 tracks: open source projects, open source communities and celebration of 20 years of internet in Romania. The first part, the projects, was about an Arduino clone from Intel (and a Linux distro to match), a Microsoft Azure sales pitch from a local distributor and a F-Droid for FirefoxOS from Ceata. The communities included Ceata (again), "Informatica la castel" summer school, ROSEdu, ProLinux and YATE, which is not quite a community. The last track brought panels and talks with some of the internet pioneers in the country.

My talk was a short one and quite generic (slides here): in an age when so much money are invested in Linux and Open Source and so much money are drawn from them, there is still a need for the community? We believe so.
programatica

03 November 2013

Get 'em while they are young

A relaxed post as for a lazy Sunday afternoon: the little one is "hacking" graphics with Inkscape on a Fedora Linux laptop.

In case the VIDEO tag does not work for you, here's a YouTube version.

28 October 2013

Romanian winners for Wiki Loves Monuments 2013

After the jury did its work, we announced the winners for the national Wiki Loves Monuments contest in Romania. The top 10 images will go in the international contest, along with winning images from the other 52 participating countries. Best of luck there!

Cetatea Rupea, judetul Brasov Castelul Corvinestilor - vedere median-frontala de pe podul de acces Alba Iulia - Catedrala Incoronarii si Catedrala Sfantul Mihail Sarmizegetusa Regia - Sanctuarul mare circular. (Zona sacra) Arhiepiscopiei Romanului și Bacăului. Cetatea Enisala Panorama Sarmizegetusa Regia panorama Incina sacra Biserica evanghelică fortificată sat IACOBENI; comuna IACOBENI Castelul Corvinestilor - vedere lateral stanga frontala de langa podul de acces Casa Artelor (fosta Hala a Macelarilor), Sibiu

24 October 2013

Autumn wallpapers

It's the season for autumn themed wallpaper backgrounds to bring their warm colors to a desktop nearby, so here are a few of my recent pictures which may fit the bill (freely licensed as CC-BY-SA, of course):

autumn wallpaper
autumn wallpaper
autumn wallpaper
autumn wallpaper

And a bonus one for the braves to laugh in the face of a vertigo-inducting image:

autumn wallpaper

21 October 2013

Hackathon

I may not be thrilled advertising Facebook, but they do were the sponsor of a big hackathon organized by ROSEdu last week-end at Politehnica University in Bucharest. For about 24 hours 15 teams of 2 to 4 hackers coded on various projects for fun, glory, learning and prizes. They were assisted by a bunch of ROSEdu volunteers and some Facebook engineers from London and Dublin. The goal was for each team to have at the end of the coding day a piece of software ready to ship.

hackathon
Unfortunately, not everything was perfect: after many successful events, this time the weakest link was the University, which kind of screwed a big multinational sponsor, an enthusiastic NGO and a lot of volunteers when the power went off for several hours. Of course, the internet connection was down too, so the organizers had to sent the teams to work from home for this interval. And this was not all: the University rented some rooms on Saturday for some exams at the Fiscal Administration, so due to that the hackathon had to be cut 2 hours.
hackathon
The teams were diverse: most of them were university students, but there was a team with all its members being high schoolers and there was an all-girls team. Hackers were running an assortment of systems: Linux, Windows, OS X. In my empirical observation (I didn't count), Linux was a plurality and as distros I noticed Mint, Ubuntu, Fedora, Debian, Gentoo. Projects targeted Android, iOS, the web or a combinations of those and were developed with a lot of mixed technologies, I saw Java, PHP, Node.js, ObjectiveC, Ruby and more.
hackathon
The power was still down at the finale, so instead of presentations on the big screen for everyone to see, the jury had to move to each table and watch presentation made on laptop batteries and mobile data connections. Less than ideal, but in the end they managed to get the job done. I followed the jury and learned more about every project: some were warm-fuzzy feel-good about recycling, some may seem useful for students newly arrived in the big city and trying to figure its transportation system and other really creepy from a privacy point of view, but all of them had or "planned" to have some "notify your friends" or "see shit your friends do" features to palate the sponsor.
hackathon

PS: incidentally, the winning team was the one who asked at some point the roaming photographer for some ideas on their interface design :)

13 October 2013

On Linux Install Fest 2013

linux install fest
Today was that time of the year again when ROSEdu organized the traditional Linux Install Fest. I managed to be there only a couple of hours, enough to get a grasp of the event and do a few things.
Being a Sunday, there were no electrician available at the university, so the light was less than perfect. Not a problem for the hackers but a challenge for the photographer.
linux install fest
The event surpassed in size the previous year, with an increase from 118 to to 139 participants (preliminary data).
linux install fest
Also, compared with the previous year, the Fedora presence increased: thanks to Iosif who sent me a package just in time, I had enough Fedora 19 DVDs to cover the event and some handy stickers. Gabriel also joined, armed with a bunch of Fedora 18 DVDs and more swag he saved from a past event this winter. And actually there were some people installing Fedora!
linux install fest
Looking at the numbers some changes are noticeable: after the last years most of the installs were Ubuntu, closely followed by Debian, this year the situation is dramatically different: no Debian install registered, the most installs are MINT with Ubuntu in a distant second place.
There are some possible explanations:
  • the Ubuntu install discs arrived 1 hour late, so early in the morning the girl at the registration desk had to reply to Unbuntu inquiries: "don't you want Mint instead? it comes in both 32 and 64 bit versions";
  • the computers in the university lab moved from Ubuntu to Mint to get away from Unity;
  • Mint was available on USB sticks, which AFAIK were for the students to keep, while the other distros were available on optical media (also for the students to keep).
From my point of view, there is also noticeable the Fedora increase: from zero to 8 students this year. Worth mentioning, almost all of them happened early in the morning (in the first hour).

Enjoy below a few more pictures from the install fest:
linux install fest
linux install fest
linux install fest