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Comment Huffman alternative (Score 1, Informative) 135

by hsa (#52511075) Attached to: Dropbox Open Sources New Lossless Middle-Out Image Compression Algorithm
I worked as a part-time assistant in Data Structures and Algorithms course 10 years ago in Helsinki University of Technology.

JPEG is a lossy compression algorithm. It does not preserve the image. It creates these blocks of image data and then compresses them using Huffmann encoding. Same encoding is used in zip-files.

Dropbox's algorithm uses these same blocks JPEG algorithm produces (meaning, that the information is still lost in compression), but uses a clever way to compress them and ditches Huffmann encoding entirely.

So, the old process was:
1. Encode image into coefficients (lossy)
2. Encode coefficient blocks with Huffmann encoding

The new process is:
1. Encode image into coefficients (lossy)
2. Encode coefficient blocks with Lepton

Pfft.. too little, too late. JPEG is "good enough" and I don't want a huge clusterfuck of incompatibility problems with my libraries.

Comment Re:What will you ACTUALLY be doing? (Score 1) 325

by hsa (#50705245) Attached to: Ask Slashdot: Selecting a Version Control System For an Inexperienced Team
I have been developing software professionally for over 10 years now.

All these weird requirements (reports, bug tracking integration, email notifications..) are .. weird. Sounds like a manager is trying to use version control system for parts of his job. Or you are talking about continuous integration, and should look elsewhere, like CruiseControl.

Nevertheless, I will never ever again do a multiperson project without a version control system. Seriously, I even use version control on my personal projects. Version control is not a "nice to have", it is a must.

--

I work in a Fortune 500 Company and I recommend TFS or SVN for version control. GIT is not nice, since it requires user training. You just want to have your team developing as fast as possible and minimize the admin tasks.

Comment Re:Yesteryears Algorithms (Score 2) 77

by hsa (#50462501) Attached to: An Algorithm To Randomly Generate Game Dungeons
Yeah, old algorithms and I wouldn't use this guy's work for my projects. You read about this stuff on a magazine. Kids these days read about this stuff on the net. I am hoping, that other media outlets have covered this as well. This article gives great ideas and hopefully inspires some future game developers, who are now in their teens.

Too bad it has some fairly advanced concepts, like Delaunay triangulation, which has been taken from a library and quite frankly - useless. Carmack himself speculated some years ago, that just pushing every wall in Doom to a modern GPU without any visibility checking would result in faster performance than raycasting or portals or any other 90s technique. And why do you need triangles, when the graphics pipeline supports quads? And why do they have to be roughly the same size? Have some faith in the GPU.

Good article. Would have been great, if it would have stuck with the trivial algorithms that do not require advanced CS courses. Spanning tree, anyone? I have have worked as a TA in university for a course teaching those subjects, but I didn't have a faintest idea about those in my teens.

Comment Re:Status was NOT divulged, only email identities (Score 0) 65

by hsa (#50449839) Attached to: UK Health Clinic Accidentally Publishes HIV Status of 800 Patients
I disagree. This was probably a mailing list, so if you receive a mail without hidden receiver addresses, like:

From: hospital.info@nhs.london.co.uk
To: hiv.center@london.co.uk
CC: Bob Burger <bob.burger@hotmail.com>, Cecil Cockburn <cecil1990@gmail.com>, David Davidson <dave@tesco.co.uk>, etc..
Subject: New treatment times for your HIV-infection and community meetings

It is not hard to imagine, that other people on the list would be infected with HIV as well..  Now the recipients know 800 other people, that have a high probability of being infected, too. How many people without HIV would actually subscribe to a newletter about it?

Comment Re:MOOCs: my worst education experiences ever. (Score 3, Interesting) 46

by hsa (#50389581) Attached to: As Coursera Evolves, Colleges Stay On and Investors Buy In
I worked as a TA in a university. There are people there also, missing deadlines and asking for higher grades. They just don't do it in front of everyone.

There is a simple solution to this problem:
- Clear, written rules for all, posted at the beginning of the course
- Enforcing those rules on forums too (people will cry, but let 'em)
- Deadlines, that give time to finish the assignments
- Deadlines, that do not move, even if they are bombing your city

I have encountered many of the same problems myself, taking MOOCs. They go away, when the instructors learn from these things and create new rules, and enforce them. This is how Coursera is evolving. The student material is the same, but the instructors learn from their previous problems with the students.

I've also noticed, that the quality of the forums is often based on a few bright inviduals , that really bring insights into conversations (and one of them was from India, and he was a better programmer than me (15 years of experience)). If everybody is a nagging idiot, well the forums are not going to be fun. That is the price we pay for free education without prequisities.

I am actually thrilled, to see Africans and other nationatilities on same courses, and graded the same as you Americans and us Europeans. They come from a totally different background and actually have to do real work, to even get materials for high level education. I wholeheartedly support bringing education to everyone, and have yet to see "free certicate" given to someone on a MOOC.

Comment Re:Statists will not go quietly into the night (Score 4, Informative) 330

by hsa (#50281005) Attached to: Finnish Police: If You See Uber Car, Call 911
I live in Finland. If you suffer a hard crash, you don't have to pay thousands of euros, since healthcare is mostly free and in case of accident, they charge you like 15 euros booking fee and some additional expenses, if you need a room at the hospital to recover. But that is like 100 euros a night on public healthcare.

Insurance is mostly for the car damage (both cars) and it is required by the law.

--

The taxis are really expensive in Finland, the base fare is ~7 euros and you pay like 2 euros/km and there is extra for the drive time. In Estonia, the taxis cost one third of our prices and they have a decent taxi system.

For all this bureaucracy our taxi cars are mostly new, top shape and drivers get tax deductions on their cars. You would think, that they know the city they drive in, but half of the time they use navigators. You can pay by credit card and I have never been scammed in a Finnish taxi.

I am sure the taxi drivers are pissed, because using cheaper cars and drivers would bring the prices down to a realistic level (like less than 50% of current prices) and taxi drivers pay a premium to the dispatch centers for getting their fares.

Mostly taxis are used on friday and satuday nights, when people get home from the clubs and pubs. Having to wait 30 minutes for a taxi in a queue is common here and that generates a lot of fights, when drunken fools try to skip the queue. If some normal working man would like to generate a little extra income on those nights, that would be just awful - for the business..

Comment Business Consulting (Score 3, Interesting) 213

by hsa (#50149633) Attached to: Why Certifications Are Necessary (Even If Aggravating To Earn)
I work as a business consultant on various IT projects. Certifications are required in my line of work.

They give points in application process when big firms and the public sector contracts us to do real projects. Even so much, that one certificate is equal to two years of work experience or more.

They have no effect on me doing my job and are all about memorizing stupid details on things I will never use. I would be more than happy if our clients would see them as a money making scam, that they really are. But such is life.

Hate 'em all you like, but silly IT managers who hire sub-contractors don't know any better.

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