• Title/Summary/Keyword: Up/down scaler

Search Result 6, Processing Time 0.019 seconds

Image scaling scheme using the intra mode information in H.264/AVC decoder (H.264/AVC 복호화기에서 복호된 인트라 모드 정보를 이용한 화면 해상도 변환 방법)

  • Chae, Jin-Ki;Han, Jong-Ki
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2013.06a
    • /
    • pp.296-299
    • /
    • 2013
  • 디스플레이 기술이 발전함에 따라 다양한 크기의 디스플레이를 탑재한 장치들이 등장하게 되었고, 다양한 디스플레이 크기만큼 다양한 해상도를 사용하고 있다. 때문에 비디오 코덱과 scaler는 보편적으로 함께 사용된다. 그러나 기존의 scaler는 비디오 코덱의 복호화기와 화면 해상도 변환 모듈이 독립적으로 구성되고, 서로 간에 정보를 이용하지 않으므로 시스템의 성능 개선에 한계가 존재하였다. 즉, 비디오 코덱의 복호화기는 비트스트림으로부터 복호한 정보를 바탕으로 영상을 복원하고, 복원영상은 up/down scaler에서 확대/축소를 수행한다. 하지만 비디오 코덱의 비트스트림에 존재하는 정보는 영상의 특성을 반영하기 때문에 up/down scaler에서 비디오 코덱의 복호화기에서 복호된 정보를 이용하면 복잡도의 증가 없이 효율적인 확대/축소를 수행할 수 있다. 이에 본 논문에서는 비디오 코덱 중 차세대 비디오 코덱인 H.264/AVC 복호화기에서 생성된 복원 영상에 대해서 별도로 영상의 특성을 계산하는 모듈 없이 H.264/AVC 복호화기에서 복원된 정보 중 인트라 모드 정보를 바탕으로 영상의 특성에 맞는 up/down scaler를 구현하는 방법을 제안한다. 이 방법은 기존의 scaler들보다 물체의 경계영역을 더 선명하게 확대하는 효과를 보인다.

  • PDF

A Study of the Combinatorial Interpolation Algorithm for Scaler Hardware Design (스케일러 하드웨어 설계를 위한 조합 보간 알고리즘의 연구)

  • Si-Yeon Han;Bong-Soon Kang
    • Journal of IKEEE
    • /
    • v.27 no.3
    • /
    • pp.296-302
    • /
    • 2023
  • As Multimedia industry has evolved, it has become possible to display resolutions in various formats. Therefore, the performance of a scaler algorithm that converts resolutions while maintaining high quality and its hardware implementation are important. Considering the hardware design of an image up/down scaler, this paper proposes a combinatorial scaler algorithm that uses modified bilinear interpolation in the vertical direction and bicubic interpolation in the horizontal direction to reduce the line memory burden. Through quantitative and qualitative evaluations, this paper compared the performance of the proposed algorithm with three other well-known algorithms, and also compared the hardware burden of its hardware implementation. This paper used a sinusoidal signal and eight typical images for performance evaluation.

Hardware Design for Real-Time Processing of a Combinatorial Interpolation Scaler with Asymmetric Down-scaling and Up-scaling (비대칭 축소 및 확대가 가능한 조합 보간 알고리즘의 실시간 처리를 위한 하드웨어 설계)

  • Si-Yeon Han;Semin Jung;Jeong-Hyeon Son;Jae-Seong Lee;Bong-Soon Kang
    • Journal of IKEEE
    • /
    • v.28 no.1
    • /
    • pp.26-32
    • /
    • 2024
  • Recently, various video resolution formats have emerged, and digital devices have built in dedicated scaler chips to support them by enlarging or reducing the resolution of input videos. Therefore, the performance and hardware size of scaler chips are important. In this paper, the combinatorial interpolation scaler algorithm proposed by Han is used to design the hardware using the line memory structure with dual-clock proposed by Han and Jung. The proposed hardware is capable of real-time processing in QHD environments, designed using Verilog, and validated using Xilinx's Vivado 2023.1. We also verify the performance of Han's proposed algorithm with a quantitative numerical evaluation of the proposed hardware.

Weighted DCT-IF for Image up Scaling

  • Lee, Jae-Yung;Yoon, Sung-Jun;Kim, Jae-Gon;Han, Jong-Ki
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.13 no.2
    • /
    • pp.790-809
    • /
    • 2019
  • The design of an efficient scaler to enhance the edge data is one of the most important issues in video signal applications, because the perceptual quality of the processed image is sensitively affected by the degradation of edge data. Various conventional scaling schemes have been proposed to enhance the edge data. In this paper, we propose an efficient scaling algorithm for this purpose. The proposed method is based on the discrete cosine transform-based interpolation filter (DCT-IF) because it outperforms other scaling algorithms in various configurations. The proposed DCT-IF incorporates weighting parameters that are optimized for training data. Simulation results show that the quality of the resized image produced by the proposed DCT-IF is much higher than that of those produced by the conventional schemes, although the proposed DCT-IF is more complex than other conventional scaling algorithms.

Joint Optimization of the Motion Estimation Module and the Up/Down Scaler in Transcoders television (트랜스코더의 해상도 변환 모듈과 움직임 추정 모듈의 공동 최적화)

  • Han, Jong-Ki;Kwak, Sang-Min;Jun, Dong-San;Kim, Jae-Gon
    • Journal of Broadcast Engineering
    • /
    • v.10 no.3
    • /
    • pp.270-285
    • /
    • 2005
  • A joint design scheme is proposed to optimize the up/down scaler and the motion vector estimation module in the transcoder system. The proposed scheme first optimizes the resolution scaler for a fixed motion vector, and then a new motion vector is estimated for the fixed scaler. These two steps are iteratively repeated until they reach a local optimum solution. In the optimization of the scaler, we derive an adaptive version of a cubic convolution interpolator to enlarge or reduce digital images by arbitrary scaling factors. The adaptation is performed at each macroblock of an image. In order to estimate the optimal motion vector, a temporary motion vector is composed from the given motion vectors. Then the motion vector is refined over a narrow search range. It is well-known that this refinement scheme provides the comparable performance compared to the full search method. Simulation results show that a jointly optimized system based on the proposed algorithms outperforms the conventional systems. We can also see that the algorithms exhibit significant improvement in the minimization of information loss compared with other techniques.

A Hardware Implementation of Image Scaler Based on Area Coverage Ratio (면적 점유비를 이용한 영상 스케일러의 설계)

  • 성시문;이진언;김춘호;김이섭
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.40 no.3
    • /
    • pp.43-53
    • /
    • 2003
  • Unlike in analog display devices, the physical screen resolution in digital devices are fixed from the manufacturing. It is a weak point on digital devices. The screen resolution displayed in digital display devices is varied. Thus, interpolation or decimation of the resolution on the display is needed to make the input pixels equal to the screen resolution., This process is called image scaling. Many researches have been developed to reduce the hardware cost and distortion of the image of image scaling algorithm. In this paper, we proposed a Winscale algorithm. which modifies the scale up/down in continuous domain to the scale up/down in discrete domain. Thus, the algorithm is suitable to digital display devices. Hardware implementation of the image scaler is performed using Verilog XL and chip is fabricated in a 0.5${\mu}{\textrm}{m}$ Samsung SOG technology. The hardware costs as well as the scalabilities are compared with the conventional image scaling algorithms that are used in other software. This Winscale algorithm is proved more scalable than other image-scaling algorithm, which has similar H/W cost. This image-scaling algorithm can be used in various digital display devices that need image scaling process.