Il Hong Shin

A New Fast Encoding Algorithm Based on an Efficient Motion Estimation Process for the Scalable Video Coding Standard

In this paper, a new fast encoding algorithm based on an efficient motion estimation (ME) process is proposed to accelerate the encoding speed of the scalable video coding standard. Through analysis of the ME process performed in the enhancement layer, we discovered that there are redundant MEs and some MEs can simply be unified at the fully overlapped search range (FOSR). In order to make the unified ME more efficient, we theoretically derive a skip criterion to determine whether the computation of rate-distortion cost can be omitted. In the proposed algorithm, the unnecessary MEs are removed and a unified ME with the skip criterion is applied in the FOSR. Simulation results show that the proposed algorithm achieves computational savings of approximately 46% without coding performance degradation when compared with the original SVC encoder.

SVC Application in Advanced T-DMB

Commercial terrestrial digital multimedia broadcasting (T-DMB) service was launched in the Republic of Korea. Reflecting recent demands of high quality video, Advanced T-DMB(AT-DMB) adopting a hierarchical modulation is being developed as the way to increase the payload data. Based on the AT-DMB system, this paper proposes a method to provide increased video quality with high spatial resolution. By using the emerging H.264/MPEG-4 AVC amendment 3 scalable extension (SVC), the proposed method is able to support high spatial resolution as well as the currently serviced spatial resolution while retaining the backward compatibility to T-DMB. In the experimental results, the benefits in terms of coding efficiency and spatial scalability are proven in comparison with the conventional T-DMB and alternative methods to provide a high spatial resolution video.

Advanced T-DMB with hierarchical modulation and scalable video coding

Reflecting the demand for a high quality video, Advanced T-DMB (AT-DMB) adopting a hierarchical modulation is being developed in order to increase the data payload. Based on the AT-DMB system, this paper proposes a method to provide the increased video quality with a high spatial resolution. By using the emerging H.264/AVC amendment 3 scalable extension (SVC), the proposed method supports a high spatial resolution as well as the currently serviced spatial resolution while retaining the backward compatibility to T-DMB. In the experimental results, benefits are shown in comparison with the conventional T-DMB and alternative methods to provide a high spatial resolution video.

Distortion estimation in CBR channel and its application for H.264 rate control

When a video sequence is compressed with rate control for a constant bit rate (CBR) channel, the visual quality usually fluctuates according to image complexity. We introduced distortion models under the CBR condition to predict distortion during rate control. The paper also proposes a control method for improvement of visual quality in H.264 CBR condition. In the experiments, we analyzed the peak signal-to-noise ratio (PSNR), the variance of the PSNR, and the average difference of the PSNR between adjacent frames for various video sequences. Our method demonstrates a more stable visual quality without severe PSNR degradation.

Discrete-cosine-transform- domain downsizing with windowing operation

A simple and effective method is presented for discrete- cosine-transform (DCT)-domain downsizing. Various methods em- ployed in DCT-domain downsizing simply reuse the frequency com- ponent of DCT, which shows a severe aliasing effect. The proposed approach extends the downsizing method for alleviating or reducing the aliasing effect with a windowing operation, which adjusts the magnitude of the DCT coefficient. Visual inspection showed satis- factory results, with no complexity overhead and performance deg- radation regarding the peak-signal-to noise ratio (PSNR) after upsampling.