Gimchi and Video Compression in the Land of the Morning Calm

Transcription

1 Gimchi and Video Compression in the Land of the Morning Calm An Experience Report About an IAESTE Internship in South Korea in 2013 Benjamin Fischer Bachelor of Science ETH in Computer Science January 4, Introduction This report is about my IAESTE internship in South Korea from September 16 until December 8, I worked at the Multimedia Security Laboratory of Korea University and lived in the capital Seoul. In September 2013, I completed my bachelor s degree in computer science at ETH Zurich. I intended to do a year with different internships to gain work experience in my field. Since long, I planned to apply for an internship through IAESTE Switzerland if the job offer suited me. My studies were full of important foundations for computer science, so I finally wished to apply them in real projects. The offer I applied for seemed a perfect opportunity to have a first taste of research and I was extremely lucky to get it. 2 Work I was part of a research group at the Multimedia Security Laboratory, which belongs to Korea University, one of the best universities in the country. I realized that this university is very challenging and many students at high school study late into their nights to have a better chance to enter it. The members of the research group included professors, senior researchers, doctoral students, master students, as well as other IAESTE trainees. The Multimedia Security Laboratory explores a variety of topics like further compression of compressed files, file carving (attempting to reassemble files from fragments without file system metadata), and steganography (hiding information in data). The project I was involved in was about improving the compression of the new video compression format HEVC. More specifically, we tried to improve the compression ratio of video files while preserving the video quality. Both my colleagues and me were not yet familiar with this format HEVC. So I was asked to study its standard to get an overview and give my colleagues an introduction into it. In mutual exchange and during meetings, we learned a lot about 1

2 Figure 1: Bowling event with multicultural colleagues HEVC and its reference software. I did not have any education specifically on video compression during my preceding studies, but on lossless compression in general. Thus, most of it was new to me. The group already developed a technique for further compression of JPEG images, which we next attempted to apply to HEVC videos. However, we concluded from our discussions that it may be better to explore different techniques. Based on a paper, I developed another technique to losslessly improve the compression ratio of HEVC videos and implemented it by changing the reference software in C++. At the end of my internship, we visited the DCS Joint Conference 2013, a local conference about information technology, for which all the members of the laboratory completed a paper. Even though this event was more like a workshop, I was quite excited to complete a scientific paper for it and go there with my colleagues. 3 Environment IAESTE Korea organized my accommodation, which was just five minutes to walk to my work place. It was a compact single room in a hostel with many young people, most of whom probably were students. The kitchen and washing machines were shared, while my room had its own toilet and shower booth. The population in Seoul is rather dense and the rent was almost half of my salary. Otherwise, the life there was not expensive at all. Korea is both convenient and safe to live. For example, the same transportation card can be used to pay for any of the sub- 2

3 Figure 2: A Korean meal for three people with various side dishes ways or buses. The subway systems are an efficient means of transport and easy to use with their signs and English translations. At the same time, I think that Korea has a wide range of development. For instance, many people use the latest smart devices, are dressed fashionably, or have plastic surgery, while on traditional markets, people bargain and work hard until a high age. However, the communication with Koreans was difficult sometimes when I was on my own. For many people it seems weird to speak to strangers in English. I have the impression that most younger Koreans do speak English well, but they seem to be reluctant to use it to the best of their knowledge. At the same time, I can understand that English is very different from their mother tongue, making it hard to even say something simple. With a couple of Korean phrases and body language, one can survive, though. What astonished me was that the Korean writing system Hangeul is actually based on pronunciation and not on meaning like Chinese characters, for example. Thus, it is not too hard for foreigners to learn how to read Korean letters slowly and approximately. Without understanding the meaning of the words, this may prove helpful to pronounce location names or parts of a menu, for instance. One discovers that there exist many words taken from English like refill, which is useful for thirsty customers in a restaurant. Mostly, I experienced Koreans being friendly, disciplined, witty, careful, and rather curious about foreigners. From my arrival at the airport on, I was guided by 3

4 volunteers of IAESTE Korea to my new home. My colleagues at work helped me a lot for my daily life like finding a comfortable blanket or opening a bank account. I had more than one surprising encounter with random people. For example, there was this father who just spontaneously introduced me to his two kids. 4 Leisure Except for breakfast, I virtually always ate at restaurants with friends. The Korean cuisine offers a great variety of meals. Korean food typically includes rice, meat, and many side dishes. The well-known side dish gimchi is made of fermented vegetables and comes in hundreds of varieties with a spicy or sour taste. The Multimedia Security Laboratory sometimes even paid for meals, during which the members had time to socialize. As I lived just next to Korea university, the surroundings were full of places for young people. With friends from work, we enjoyed having a drink together, singing in a Karaoke room, or going for bowling. There is a hot rivalry between the most prestigious private universities of Korea, namely Yonsei University and Korea University. Once every year, there are sports games between these two universities accompanied by various festivals. We went to a part of these thrilling games, cheering for our university. During the festivals, countless students gathered around our university and celebrated together. IAESTE Korea regularly organized events. These were either meals together in Seoul or trips on weekends. The guidance was rather professional and gave me a detailed introduction into the culture, history, and lifestyle of Korea. As there were not that many trainees, the atmosphere during the events was nicely personal. For example, we visited the historical city of Gyeongju or stayed overnight at a Buddhist temple in the middle of a national park. One of my favorite trips was when we flew to the island of Jeju. This volcano island is home to a fascinating scenery of nature and excellent seafood. At the time, the two people working for IAESTE Korea and two of their Korean friends traveled with us five IAESTE trainees. Together, we rent a van and toured around the island for three days. 5 Conclusion All in all, this IAESTE internship will be one of the most memorable times in my life. Not only am I truly lucky to gain such a first work experience in research. With an IAESTE exchange, I can learn about the life in a culture so different from my own. I think as long as I am young, I like to do the experiment of totally changing my environment from time to time. 4

5 Figure 3: On the island of Jeju during a trip with IAESTE Korea 5