Alexey Smirnov's blog

One of the best things that you can enjoy if you are a graduate student in the United Sates is opportunity to meet renowned researchers. When I was at Stony Brook University it was called Distinguished Lecture Series. Through this series I have met a lot of interesting people, for example Charles Leiserson, Avi Silberschatz, Randy Katz, etc. There were also lectures of Michael Brin, the father of one of Google founders as well as Hector Garcia-Molina, their academic advisor but unfortunately I have not attended their talks.

When I was an undergraduate student in early 2000s I worked in a research lab at Intel Nizhny Novgorod site. We have worked on a light field mapping project whose goal was to re-build a 3D model of an object from a hundred of images and render it quickly from an arbitrary angle. At that time I got to know the research projects of Graphics lab in Stanford University, in particular that of Prof. Marc Levoy. At that time I was considering going to graduate school but of course a PhD program at Stanford was extremely competitive to get in. So I ended up in SUNY Stony Brook.

This is where I met one of the former students of that lab, Olaf Hall-Holt. He was working on visualizing urban areas. At that time I was a lot more interested in other areas of computer science even though I spent some time at Intel working in computer graphics project. But it was nice to meet Olaf as a connection with the Stanford graphics lab.

In a couple of years while I was working on computer security issues at SUNY another representative of Stanford graphics lab visited SUNY. It was Pat Hanrahan. He was giving his distinguished lecture.

I have left Stony Brook in 2006 and eventually went to work for a big company in Finland. And a few days ago I have got a chance to meet another professor from Stanford Graphics Lab – Marc Levoy. He was describing his recent work but when I asked him whether he still works on light fields he answered that yes he is applying that work to microbiology.

To summarize, during the span of almost 10 years I have been working in different areas of computer science such as security, mobile technology, and others. But wherever I am I keep on meeting people from Stanford graphics lab. Is not that surprising? I am wondering after all if I should have sticked with the first project on computer graphics that I worked on at Intel instead of trying out so many exciting things. Another surprising finding is that the work that I am doing now is related to that of Stanford graphics lab, even though it might look as two different areas at a first glance. Is there some hidden connection that keeps me close to graphics?

I am to run the Long Training Run #1 in Central Park this Saturday. This is an unscored noncompetitive race where participants get divided into pace groups and cover from 6 to 20 miles. The temperature outside is 90F and it is unlikely to get much cooler. So it is kind of a 30×30 race: 30 km at 30 centigrade.

It was great. I have completed 20 miles. The weather was not very hot in the beginning as we started at 7am. However, the heat kicked me out on the final lap at around 10am. So the finish was not that great. The course included four laps of different length: a 6-mile, 2×5-mile, and a final 4-mile loops. The longest lap is the complete loop of the park. The smaller ones are when you shortcut the upper and lower parts.

Compared to the Bronx half-marathon, I was able to run 16 miles at the 9 minutes per mile pace which is a 10 mile improvement. In the Bronx, the sun kicked me out after 7th mile or so. Let us see if the progress will remain as steady, but the learning curve typically gets flatter as time goes on. The long lasting heat over 100 degrees in the east helped me a lot.

I have read a couple of other IEEE magazines last week:

• Spectrum, one of the few periodicals that are positive on the upcoming Sony PS3. They emphasize their architectural benefits without much consideration of their applicability. In the August 2006 issue Expressway to your skull article presents the memory subsystem of the game console. Its total CPU-memory bandwidth is 25.6 GB/sec which is twice as much as that of a PC. The enabling technology is differential signaling when two wires are used to send one bit. Setting one of the wires to a high voltage and the other to a low voltage means one, the opposite means zero. This reduces the probability of noise-related errors.
• Computer, this time describing advances in computational photography. It all started with camera obscura, then people wanted to improve it because the sensor did not receive enough light, so they added a lens. A number of interesting effects, for example wide-angle, high dynamic range, depth imaging were enabled with more lenses, mirrors, and masks. As the hardware advanved, so did the computational effort to make use of the captured data. For example, using volumetric aperture allows one to implement split field-of-view imaging when certain image parts receive higher resolution than others. A special illumination pattern allows one to extract a depth field and separate global illumination from direct one. An array of cameras makes it possible to see behind the trees. A microlens array in front of a camera sensor allows one to refocus a captured image. A number of images taken from different angles is the technology behind the light field mapping. Its idea is to render an image at any angle using an approximation of captured images. A robotic arm with a number of degrees of freedom takes those images. I have been exposed to this technology in Microprocessor Research Lab, Intel working in R. Grzeszczuk project. Our team based in Nizhny Novgorod, Russia was responsible for a DirectX/OpenGL? viewer. It is available open-source. Marc Levoy has described this technology in his article and predicted its applications in consumer electronics. According to him, most cameras will include light-field capabilities in the next 25 years that will allow them to refocus, extend depth of field, change viewpoint. However, the albums will remain as they are: plain images rather than holograms or movies.

Pictures

This summer is a very busy one. After returning from the Formula 1 and taking part in the Bronx Half-Marathon I am working on the advanced signature generation project. The idea is to slice the vulnerable program to generate a signature. However, the standard algorithms generate a slice which is too big. We are trying to remove the redundancy from it. The project is implemented as a Scheme module loaded to the source code analysis tool Codesurfer.

I am also catching up on reading after a long run on Saturday and the subsequent day off Sunday. Books of interest are:

• Muchinck. Advanced Compiler Design and Implementation.
• Leo Tolstoy. War and Piece. Volume 1, Volume 2 in progress. Tolstoy is the writer of the summer. I enjoy his works from when I read his novels first time many years ago till now. This particular work is also a great introduction to French for those who do not know it.

The summer is not particularly hot and I am so busy that I was at the beach only once. Let us see if I will go there in August.

I was in Indianapolis this weekend attending Formula 1 US Grand Prix. It was impressive. You have to see it alive rather than on the TV. The cars are so noisy. The Stand B seat across the pitlane was a great place to watch the race but it was difficult to survive when the cars were heading toward the start: they all stopped across where I was and then roared the engines staying at where they were. When engines of 20 Formula 1 cars work at a high RPM you have to take care of your ears… From the stand I was able to see the start-finish line, the pits, the other side of the circuit, the award ceremony. The only thing I did not see from there was the first turn accident when Nick Heifeld was kicked up in the air and spinned a few times. I have pictures but I am not allowed to release them to public. The 12x optical zoom of a 2 megapixel Panasonic DMZ camera was very helpful.

Indianapolis pics

I am starting to prepare myself to NYC marathon this Fall. The regular training begins next week. The schedule is available online. To get an idea of what a marathon is I am going to run Bronx half-marathon on July 9. The longest timed run I have attempted previously was 5K Turkey trot here in Stony Brook. I finished 40th with 22:29 time.

There are three sport events this weekend in Europe: the final of Roland-Garros in Paris, a Formula 1 grand-prix in Silverstone, and soccer cup in Germany. Has anything like this taken place before?

• Formula 1: Alonso, M. Schumacher, Raikkonen.
• French open: Rafael Nadal.
• Holy Roman Empire: France-Italy in the final of World Soccer Cup.

I was using drcat and found a denial of service vulnerability different from a previously published buffer overflow. It allows a local unprivileged user to shut down the daemon.

If you set up a connection with the locally running daemon and shut it down immediately then the daemon will terminate. Drcatd sends a “drcatd” message and several other messages prior to forking a thread. Function local_send takes care of the case when send() terminates with -1. However, if a local socket is shut down then SIGPIPE is sent along with the error code unless MSG_NOSIGNAL is set. man send.

I have stumbled upon a number of articles on extortion viruses recently. This type of virus had been around for at least 10 years, but they receive attention these days as real money is involved:

Buy a drug from an online pharmacy to get your files decrypted

This one has been cracked because it used a fixed password mf2lro8sw03ufvnsq034jfowr18f3cszc20vmw. But there are methods that use a per-user password as described in Malicious cryptography, part one. The idea is to generate a secret key on the victim machine, encrypt files with it, then encrypt the key with the key that arrived with the virus and transmit the result to the attacker. When the money is paid the attacker will ask the victim to send the encrypted secret key and decrypt it. Once the victim receives the cleartext secret key he/she will use it to decrypt the harddrive.

U. Washington Crypto Course Video