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Ms. Lina Jin started her PhD study from January 2011 at the Computing Imaging group, Department of Signal Processing, Tampere University of Technology, Finland. Since 2011, She has been co-supervised by Prof. C.-C. Jay Kuo from the University of Southern California. From October 2013 to December 2014, she has been working at Prof. Kuo’s Media Communications Lab as a visiting scholar.

Congratulations to Lina Jin for passing her public examination on January 30, 2015. The title of her dissertation is “Perceptual Quality Assessment for Visual Signal”. Her dissertation was pre-examined by Prof. Patrick LeCallet (Université de Nantes/Ecole Polytechnique de l’Université de Nantes, France) and Prof. Weisi Lin (Nanyang Technological University, Singapore). The opponent is Prof. Mårten Sjöström from Mid Sweden University, Sweden.

With the rapid growth of information technology and the Internet, image and video have become one part of our everyday life and their quality is of prime importance for numerous applications. The aim of realistic digital image and video is to create accurate, high quality imagery, which faithfully represents the physical environment. The ultimate goal is to create images that are perceptually indistinguishable from the actual scene. Thus, the automatic evaluation of image and video quality plays a critical role in the fields of image and video processing and there are many practical applications, such as quality monitoring to maintain Quality of Service (QoS) requirements, the evaluation of video processing for compression, and perceptually optimal design of video processing systems. Ms. Lina Jin’s dissertation investigates and analyses image artifacts resulting from various 2D and 3D image/video applications and explores human visual perception of different image artifacts through subjective experiments. She conducted in designing and building a large new image quality database, TID2013. TID2013 provides [...]

Congratulations to Mr. Pang-Cheng (Brian) Lan for passing his Qualifying Exam on January 22, 2015. The title of Brian’s thesis proposal is “Enhancing Secrecy in Wireless Environment with Only Channel State Information: Theory and Applications”. His Qualifying Exam committee consisted of Jay Kuo (Chair), Keith Chugg, Andy Molisch, Salman Avestimehr and Wlodek Proskurowski (Outside Member).

In his proposal, Brian shows the advantages of having only transmitter-side channel state information (CSI) but none or limited CSI at the receiver and the eavesdropper in wiretap channels. With CSI only at the transmitter (CSIT), distortion and interference on the main channel can be pre-compensated by the transmitter to facilitate detection at the receiver while leaving the eavesdropper confused by the uncertainties of its own channel. These ideas are first tested in the case of finite-alphabet discrete memoryless wiretap channels, where the secrecy capacity expression is derived, and are then applied to two practical scenarios, namely, fading wiretap channels and those with Gaussian interference. Truncation-based schemes are proposed to ensure that the transmission occurs only when the main channel is sufficiently reliable. Furthermore, a practical unitary modulation scheme is recommended as application of exploiting the benefits of having CSIT in secrecy for multi-antenna communication systems in which Long Term Evolution (LTE) is used as an example. The achievable secrecy rates of the proposed schemes are derived and asymptotic or approximate expressions are proposed for the optimization purpose. The effectiveness of the proposed transmission schemes and the advantages of having only CSIT are demonstrated through numerical simulations.

Two research  findings of the USC Media Communications Lab were presented at the IEEE International Conference on Consumer Electronics (ICCE), which was held from January 9th to 12th 2015, in Las Vegas .

Auto exposure (AE) control is an important function of modern digital cameras. Simple AE algorithms are designed for a specific type of camera sensors. Advanced AE techniques have been developed to tackle a wider class of camera sensors and/or high contrast lighting conditions, yet they are computationally intensive and, thus, difficult to implement in a resource-constrained environment such as phone cameras. Besides, none of existing solutions provides robust performance if erroneous exposure occurs. To address the aforementioned shortcomings, a fast and robust AE algorithm is  in need. The first paper entitled with “Fast and Robust Camera’s Auto Exposure Control Using Convex or Concave Model”, co-authored by Yuanhang Su and C.-C. Jay Kuo, proposed a concave/convex function model for the luminance characteristics of a camera. Based on such a model, a proper parameter value can be computed using a modified secant algorithm with fast convergence. This paper was presented by an MCL member, Joe Lin.

The second paper entitled with “Uncalibrated Multiview Synthesis based on Epipolar Geometry Approximation”, co-authored by Young Ju Jeong, Hyoseok Hwang, Dongkyung Nam and C.-C. Jay Kuo, was mainly conducted in Samsung Advanced Institute of Technology (SAIT) with the input from Professor Kuo. This paper proposed an  efficient multiview rendering algorithm that takes uncalibrated stereo as the input. First, the epipolar geometry of multiple viewpoints is analyzed for multiview display. Then, the camera pose for an arbitrarily selected viewpoint is estimated by algebraic approximation. Finally, by exploiting rectification homographs and disparities of rectified stereo, one can determine multiview images with [...]

Xue Wang, a recently graduated Ph.D. student from Media Communications Lab at USC, decides to continue her research work as a postdoctoral associate here with us. She is so happy to study with Professor Kuo and other lab members. Now we have an interview with her, talking about the change of roles between a Ph.D. student and a post-doc researcher and lifelong study plan.

Could you briefly describe yourself and your current research?

My research is an extension of the previous work on the objective evaluation of cataract surgical techniques using image processing and computer vision methods. The state-of-art surgeon evaluation tools primarily require human observers to fill out a grading questionnaire after viewing a video of the procedure, a technique that is subject to observer bias and variability. Therefore, it is hoped that our work could be extremely helpful in developing reliable computational analysis methods that can precisely and automatically identify quantitative and qualitative evaluation for surgical techniques.

Why do you choose to take a post-doc position and what’s your future plan?

I set up my career goal to become a faculty in the university when I started my Ph.D. at USC. I enjoy doing research and communicating with fellow workmates, and working as a post-doc is necessary step in the preparation for becoming faculty. To make this decision, I talked with different professors about the ongoing research work and future plan. Also, I got great help from Jing Zhang, one of our MCLab alumni, who is now pursuing her post-doc at Yale University. I’d apply for faculty position in future and I need to improve myself more. One aspect is about the research; I will enhance my work and try to seize any off-campus presentation opportunity [...]

In 2014 Fall semester, Chien-Yi Wang will become a new Ph.D. student in MCLab. Chien-Yi Wang received the B.S. degree in Electrical Engineering from National Taiwan University in 2013. He arrived at USC a month ago, and now we have an interview with him, talking about his background and his thoughts on USC and MCLab.

What were your first impression of USC and MCLab?

I have heard of USC in its great learning environment and plenty of resources. At first sight, the buildings in USC are amazing and beautiful. There are usually many trees and animals around the campus, bringing lots of energy and spirits. I also notice that there are always some comfortable benches and tables, accompanying with fabulous fountains, for people to study and chat outside. I am so excited and cannot wait to study in this wonderful campus.
As for MCLab, I think people here are really nice and friendly. Some senior students in the lab introduce many places in the campus for me, and try to help me to get used to the life in Los Angeles. I also got many assistances and advices from them in academy and living before I entered the school. It’s really great to become one of this big warm family.

Could you briefly describe your previous research experience?

In the last two years of my B.S. program, I joined the Wireless Communication Lab and initiated a research project on multimedia communication subject. I have studied the protocols of different wireless systems and learned how to use complex encoding technologies such as H.264 on video sources. I found it interesting to design some algorithms and implement them on the wireless driver. I finally proposed a scheme to improve the [...]