• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.9 no.1
• /
• pp.53-59
• /
• 2009

Multi-view video is necessary to develop a new compression encoding technique for storage and transmission, because of a huge amount of data. Layered depth image is an efficient representation method of multi-view video data. This method makes a data structure that is synthesis of multi-view color and depth image. This paper proposed enhanced compression method by presentation of efficient layered depth image using real distance comparison, solution of overlap problem, and interpolation. In experimental results, confirmed high compression performance.

• Journal of Korea Multimedia Society
• /
• v.9 no.8
• /
• pp.963-970
• /
• 2006

In this paper, we proposed a motion picture processor for using low-cost color super twisted nematic liquid crystal display(CSTN-LCD). The proposed processor apply a new driving scheme using SFP(Subgroup Frame Pattern), so we extends gray scale and eliminates flicker phenomenon. In addition, we apply the BFI (Black Field Insertion) to the design compensated for response time of a LC (Liquid Crystal). We use an edge enhancement and interpolation method to improve image quality of motion picture. The hardware architecture of proposed processor has been implemented and verified on a prototype FPGA board. The proposed method can be used in the display devices such as PDA(Personal Digital Assistants), mobile phone, and PMP(Portable Multimedia Player).

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.3
• /
• pp.1011-1025
• /
• 2014

A demosaicing method for a Bayer-like W-RGB color filter array (CFA) is proposed. When reproducing images from a W-RGB CFA, conventional color separation methods for W-RGB CFA are likely to cause blurring near the edges due to rough averaging using a color ratio of neighboring pixels. Moreover, these methods cannot be applied to real-life digital cameras with W-RGB CFA because the methods were proposed under an ideal situation, W=R+G+B, not a real-life situation, $W{\neq}R+G+B$. To improve edge performance, we propose a method of constant color difference assumption with inversed weight, which uses information from all edge directions for interpolating all missing color channels. The proposed method calculates the correlation between W, R, G, and B to enable its application to real-life digital cameras with W-RGB CFA. Simulations were performed to evaluate the proposed method using images captured from a real-life digital camera with W-RGB CFA. Simulation results shows that we can demosaic by using the proposed algorithm compared with the conventional one in about +34.79% SNR, +11.43% PSNR, +1.54% SSIM and 14.02% S-CIELAB error. Thus, the proposed method demosaics better than the conventional methods.

• Journal of Broadcast Engineering
• /
• v.14 no.6
• /
• pp.742-748
• /
• 2009

Most commercial digital still cameras use a single sensor array (e.g., CMOS or CCD) with color filter array (CFA) to reduce the cost and size. Since the image obtained with CFA has only one color value per pixel, the demosaicing is needed to acquire missing two color values. Although many demosaicing methods have been proposed, they still have artifacts such as rainbow and zippering artifact. In this paper, we propose the simple demosaicing algorithm using tendency of neighbor pixels with the enhanced weighting function. In the experimental results, our algorithm shows much better subjective qualities of the images than conventional demosaicing algorithm and improves objective qualities.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.04c
• /
• pp.265-267
• /
• 2003

해부학적 구조의 변형이 존재하는 신체 부위를 정합하기 위하여 연구되는 non-rigid 정합 방법은 현재 의료 영상 분야에서 매우 중요한 주제이고 많은 연구가 이루어지고 있다. 본 논문에서는 Visible Human Color 단면 영상과 CT영상 사이에 존재하는 다리 모양의 변형을 정합 하기 위하여 계층적인 non-rigid 정합 방법을 제안하였다. 제안한 계층적 정합 방법은 영역 경계를 이용한 global rigid 정합으로 초기 변형 벡터를 찾고. 정합 할 영역을 sampling하여 local non-rigid 정합을 수행 한 후 결과를 interpolation하여 전체 영역에 대한 최종 정합 벡터를 계산하였다. 결과적으로 더욱 효율적이고 강력한 non-rigid 정합 결과를 얻을 수 있었다.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.11 no.4
• /
• pp.155-164
• /
• 2015

In this paper, we propose a new color interpolation method based on trilateral filter approach, which not only preserve the high-frequency components(image edge) while interpolating the missing raw data of color image(bayer data pattern), but also immune to the image noise components and better preserve the detail of the low-frequency components. The method is the trilateral filter approach applying a gradient to the low frequency components of the image signal in order to preserve the high-frequency components and the detail of the low-frequency components through the measure of the freedom of similarity among adjacent pixels. And also we perform Gaussian smoothing to the interpolated image data in order to robust to the noise. In this paper, we compare the conventional demosaicing algorithm and the proposed algorithm using 10 test images in terms of hue MAD, saturation MAD and CPSNR for the objective evaluation, and verify the performance of the proposed algorithm.

• International journal of advanced smart convergence
• /
• v.11 no.2
• /
• pp.13-21
• /
• 2022

In this paper, we propose a learning based joint demosaicing and super-resolution framework which uses only the mosaiced color filter array(CFA) image as the input. As the proposed method works only on the mosaicied CFA image itself, there is no need for a large dataset. Based on our framework, we proposed two different structures, where the first structure uses one deep image prior network, while the second uses two. Experimental results show that even though we use only the CFA image as the training image, the proposed method can result in better visual quality than other bilinear interpolation combined demosaicing methods, and therefore, opens up a new research area for joint demosaicing and super-resolution on raw images.

• Journal of Korea Multimedia Society
• /
• v.4 no.4
• /
• pp.316-323
• /
• 2001

Gamut mapping is a technique that acts on cross-media color reproduction to transform a color between devices for the purpose of enhancing the appearance or preserving the appearance of an image. Gamut mapping essentially produces color conversion error which depends on the gamut mapping method, source and destination devices, and sample points for gamut modeling. For color space conversion between monitor colors and printer colors, empirical representation using sample measurements is currently widely utilized. Color samples are uniformly selected in the device space such as CMY or RGB, represented as color patches, and then measured. However, in the case of printer, these color samples are not evenly distributed inside the printer gamut and the color conversion error is increased. Accordingly, this paper introduces a equally distributed color sampling method in CIELAB space, a device- independent color space, to reduce color conversion error, and the performance is analyzed via color space conversion experiments using three-dimensional interpolation.

• Journal of Biomedical Engineering Research
• /
• v.30 no.1
• /
• pp.34-40
• /
• 2009

Transforms including translation and rotation are required for registering two or more images. In medical applications, different registration methods have been applied depending on the structures: for rigid bodies such as bone structures, affine transformation was widely used. In most previous research, a single transform was used for registering the whole images, which resulted in low registration accuracy especially when the degree of deformation was high between two images. In this paper, a novel registration method is introduced which is based image sub-division and bilinear interpolation of transformations. The proposed method enhanced the registration accuracy by 40% comparing with Trimmed ICP for registering color and MRI images.

• Proceedings of the KIEE Conference
• /
• 2005.07d
• /
• pp.2864-2866
• /
• 2005

색역폭 사상은 디스플레이 장치간의 색재현성 차이를 보정하기 위한 기법이다. 본 논문에서는 사면체 보간에 의한 실시간 색역폭 사상을 제안하고자 한다. 기존의 제안된 육면체 보간 방식에 비해 이 논문에서 제안된 사면체 보간(tetrahedral interpolation) 방법은 색공간의 분할을 통해 분할된 각각의 사면체 색 공간에서 색역폭 사상이 수행됨으로서 왜곡이 감소되고 육면체 보간이 8개의 룩업테이블을 사용하는데 비해 4개의 룩업 테이블을 사용함으로서 실시간 처리속도의 향상과 하드웨어의 구현 시 비용절감을 기대할 수가 있다.