Chan-Seob Park

Fast coding algorithm based on adaptive coding depth range selection for HEVC

The JCT-VC is developing the next-generation video coding standard, called high efficiency video coding (HEVC). In HEVC, there are three units in a block structure. These units are a coding unit (CU), a prediction unit (PU), and a transform unit (TU). The CU is the basic unit for region splitting (like a macroblock). The CU performs recursive splitting into four blocks of equal size, starting from the treeblock. We use mode information of the current CU to avoid unnecessary CU splitting. To reduce the computational complexity, we propose a depth range selection mechanism (DRSM) using a selecting adaptive depth range. This depth range selection mechanism allows for effective splitting by only processing CUs that need this process. Experimental results show that the proposed algorithm achieves an approximate 48% reduction in encoding time for Random Access HE, compared to the HEVC test model (HM) 6.0 encoder with a BD-bitrate loss of 1.2%.

Novel fast PU decision algorithm for the HEVC video standard

In this paper, we propose a fast PU decision method to reduce encoder complexity. We use an early PU decision in each CU-level based on spatio-temporal analyses and depth correlations. We also consider a classification of motion activity. Experimental results show that the encoding complexity can be reduced by up to 37.98% on average in the random access Main profile configuration with only a small bit-rate increment and a PSNR decrement, compared to high efficiency video coding test model (HM) 7.0 reference software.

Fast Coding Unit (CU) Depth Decision Algorithm for High Efficiency Video Coding (HEVC)

In this paper, we propose a fast CU depth decision algorithm for high efficiency video coding (HEVC) technology to reduce its computational complexity. In 2Nx2N prediction unit (PU), the proposed method compares to rate-distortion (RD) cost and determines the depth using the compared information. Moreover, in order to speed-up the encoding time, the efficient merge SKIP detection method is developed additionally based on the contextual mode information of neighboring CUs. Experimental result shows that the proposed algorithm achieves the average time-saving factor of 43.67% in the random access (RA) at Main profile configuration with the HEVC test model (HM) 10.0 reference software. Compared to HM 10.0 encoder, a small BD-bitrate loss of 0.55% is also observed without significant loss of image quality.

Novel Intermode Prediction Algorithm for High Efficiency Video Coding Encoder

The joint collaborative team on video coding (JCT-VC) is developing the next-generation video coding standard which is called high efficiency video coding (HEVC). In the HEVC, there are three units in block structure: coding unit (CU), prediction unit (PU), and transform unit (TU). The CU is the basic unit of region splitting like macroblock (MB). Each CU performs recursive splitting into four blocks with equal size, starting from the tree block. In this paper, we propose a fast CU depth decision algorithm for HEVC technology to reduce its computational complexity. In PU, the proposed method compares the rate-distortion (RD) cost and determines the depth using the compared information. Moreover, in order to speed up the encoding time, the efficient merge SKIP detection method is developed additionally based on the contextual mode information of neighboring CUs. Experimental result shows that the proposed algorithm achieves the average time-saving factor of 44.84% in the random access (RA) at Main profile configuration with the HEVC test model (HM) 10.0 reference software. Compared to HM 10.0 encoder, a small BD-bitrate loss of 0.17% is also observed without significant loss of image quality.

Efficient Wireless Vibration Data Sensing and Signal Processing Technique Based on the Android Platform

Recently, many researches on big-data sensing and analysis have been actively promoted. The big data, which is generated by the digital and networked environment, is referred to to form not only numerical data, but also large-scale data for storing image data and character. Usually, many data measured through sensors are very large in scale in various vibration measurements. Measurement methods for vibration analysis currently consist of a general sensing scheme using cabling to obtain vibration data. The system is difficult to use efficiently in a location where equipment installation is not easy. We proposed a novel vibration measurement system that includes a main hardware module and a wireless data transceiver module. The system is easy to use and field data are transmitted to a remote location using Bluetooth communication and the Android platform. Nonexpert personnel can obtain field vibration data for transport, even over long distances. Through experiments in field test, we verify that the stable remote sensing range reaches up to 150 m in real-time communication without any data loss.

Performance analysis of inter-layer prediction in scalable extension of HEVC (SHVC) for adaptive media service

Abstract Scalable video coding (SVC) has been a popular research topic to provide an adaptive media service for many years. To deliver very high quality content such as ultra high definition (UHD) video in various environment, a scalable extension of high efficiency video coding (SHVC) has been developed by the Joint Collaborative Team on Video Coding (JCT-VC) of ISO/IEC MPEG and ITU-T VCEG. This paper introduces the SHVC standard technology and analyzes the performance of inter-layer prediction as an important feature. Unlike the previous scalable video coding technologies, the SHVC standard employs a multi-loop decoding structure. Also, inter-layer prediction scheme is used to remove the redundancy between layers when encoding enhancement layer syntax elements, such as motion parameters and the intra prediction mode. This paper reviews inter-layer prediction techniques that have been developed for the SHVC standard. The performance of inter-layer prediction techniques is verified and analyzed using the SHVC reference software 5.0.

Multi-scale based motion estimation for high quality video coding

Block-based motion estimation (ME) has been widely used in various video coding standards due to its effectiveness removing temporal redundancy. It plays a key role in the transmission and storage of video signals at reduced bit rates. In this paper, a novel motion estimation algorithm is proposed to enhance video quality by reflecting enlarging and reducing movements such as zoom in/out scene. The experimental results show that the proposed algorithm achieves average quality enhancement of 1.19dB (up to 2.34db) in PSNR gain with acceptable increment of ME time.

Adaptive inter-layer prediction algorithm for scalable extensions of high efficiency video coding

A method for enhancement of inter-layer reference (ILR) picture quality based on enhancement of temporal layer reference pictures with an up-sampled base layer picture is presented. The proposed scheme uses smoothing and sharpening filters to enhance the quality of inter-layer prediction. Based on two filters, a competitive scheme is proposed to get better quality of video. Experimental results showed that average BD-rate gains of 1.5%, 2.1%, and 1.7% for Y, U and V components, respectively, were achieved, compared with SHVC reference software 5.0.

Fast Inter Mode Decision Algorithm for H.264/AVC Video Encoding System Based on Correlation of Macroblock

To more effectively reduce temporal and spatial redundancy in the MPEG-4 Part-10 AVC/H.264, motion compensation uses variable block sizes and directional inter prediction investigates all available coding modes to determine the best one. However, these functions are performed for all variable block sizes, high complexity results due to the large number of combinations of coding modes. The researchers propose a fast inter mode decision to reduce the number of combinations of candidate modes using predictive data from macroblock correlations of adjacent frames. An adaptive thresholding scheme using the rate-distortion costs of neighboring blocks is applied for an early decision of the best macroblock in the inter-mode search process.