• Journal of the Institute of Convergence Signal Processing
• /
• v.6 no.2
• /
• pp.74-81
• /
• 2005

As the multimedia data increases, various scene change detection algorithms for video indexing and sequence matching have been proposed to efficiently manage and utilize digital media. In this paper, we propose a robust scene change detection algorithm for video sequences with abrupt luminance variations. To improve the accuracy and to reduce the computational complexity of video indexing with abrupt luminance variations, the proposed algorithm utilizes edge features as well as color features, which yields a remarkably better performance than conventional algorithms. In the proposed algorithm first we extract the candidate shot boundaries using color histograms and then determine using edge matching and luminance compensation if they are shot boundaries or luminance changes. If the scene contains trivial brightness variations, the edge matching and luminance compensation are performed only for shot boundaries. In experimental results, the proposed method gives remarkably a high performance and efficiency than the conventional methods with the similar computational complexity.

• Journal of the Institute of Convergence Signal Processing
• /
• v.10 no.1
• /
• pp.13-22
• /
• 2009

In this paper, we propose the 3D shape reconstruction method that combine the mosaic method and the active stereo matching using the laser beam. The active stereo matching method detects the position information of the irradiated laser beam on object by analyzing the color and brightness variation of left and right image, and acquires the depth information in epipolar line. The mosaic method extracts feature point of image by using harris comer detection and matches the same keypoint between the sequence of images using the keypoint descriptor index method and infers correlation between the sequence of images. The depth information of the sequence image was calculated by the active stereo matching and the mosaic method. The merged depth information was reconstructed to the 3D shape information by wrapping and blending with image color and texture. The proposed reconstruction method could acquire strong the 3D distance information, and overcome constraint of place and distance etc, by using laser slit beam and stereo camera.

• Journal of Broadcast Engineering
• /
• v.5 no.1
• /
• pp.41-49
• /
• 2000

In this paper, we propose a new method of indexing and searching based on object-specific features at different semantic levels for video retrieval. A moving trajectory model is used as an indexing key for accessing the individual object in the semantic level. By tracking individual objects with segmented data, we can generate motion trajectories and set model parameters using polynomial curve fitting. The proposed searching scheme supports various types of queries including query by example, query by sketch, and query on weighting parameters for event-based video retrieval. When retrieving the interested video clip, the system returns the best matching event in the similarity order.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.43 no.1 s.307
• /
• pp.45-54
• /
• 2006

This paper proposed color matching technique, including display characterization, chromatic adaptation model, and gamut mapping and extension, to generate consistent colors for the same input signal in each display device. It is necessary to characterize the relationship between input and output colors for display device, to apply chromatic adaptation model considering the difference of reference white, and to compensate for the gamut which display devices can represent for reproducing consistent colors on DTV display devices. In this paper, 9 channel-independent GOG model, which is improved from conventional 3 channel GOG(gain, offset gamma) model, is used to consider channel interaction and enhance the modeling accuracy. Then, the input images have to be adjusted to compensate for the limited gamut of each display device. We proposed the gamut mapping and extension method, preserving lightness and hue of an original image and enhancing the saturation of an original image in xy chromaticity diagram. Since the hmm visual system is more sensitive to lightness and hue, these values are maintained as the values of input signal, and the enhancement of saturation is changed to the ratio of input and output gamut. Also the xy chromaticity diagram is effective to reduce the complexity of establishing gamut boundary and the process of reproducing moving-pictures in DTV display devices. As a result, reproducing accurate colors can be implemented when the proposed method is applied to LCD and PDP display devices

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.9 no.5
• /
• pp.225-232
• /
• 2009

In this paper, a new face detection method based on pupil color distribution maps with the frequency under the illumination variance is proposed. Face-like regions are first extracted by applying skin color distribution maps to a color image and then, they are reduced by using the standard deviation of chrominance components. In order to search for eye candidates effectively, the proposed method extracts eye-like regions from face-like regions by using pupil color distribution maps. Furthermore, the proposed method is able to detect eyes very well by segmenting the eye-like regions, based on a lighting compensation technique and a segmentation algorithm even though face regions are changed into dark-tone due to varying illumination conditions. Eye candidates are then detected by means of template matching method. Finally, face regions are detected by using the evaluation values of two eye candidates and a mouth. Experimental results show that the proposed method can achieve a high performance.

• Journal of Broadcast Engineering
• /
• v.17 no.6
• /
• pp.911-923
• /
• 2012

Recently, 3DTV and 3D displays have been released in the market. Accordingly, the production of stereoscopic images has gained much interest. Stereoscopic image being composed of left and right images are currently delivered to viewers without any modifications. The researches on the enhancement of depth perception using high-frequency components and the re-production of natural color by color compensation have been carried out for 2D images. The application of such 2D technologies to 3D stereoscopic images is an aim of this paper. This paper proposes the enhancement of 3D perception by color transformation. For this, we propose a stereo matching method for obtaining a depth map and two color transformation methods such as contrast transformation and background darkening. The effectiveness of the proposed method was verified through experiments.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2003.11a
• /
• pp.294-297
• /
• 2003

최근 3차원 영상의 압축 방법에 대한 연구가 여러 분야에서 활발히 이루어지고 있으며, 특히 MPEG에서는 이와 관련하여 Exploration Experiment를 통하여 효율적인 기법을 연구하고 있다. 본 논문에서는 EE3를 위하여 스테레오 비디오 압축을 위한 효율적인 블록기반 시차예측 기법을 제안한다. 제안된 알고리즘은 스테레오 영상의 특성 중 주변 블록의 시차 벡터가 유사하다는 점을 이용하여 주변의 시차벡터를 예측 파라미터로 사용함으로써 계산량을 감소시킬 수 있었다. 또한, 예측 오차가 큰 객체의 경계면에서 블록의 크기를 4분할로 분할하여 시차 벡터를 재검색 하는 기법으로 경계 블록에 대한 예측 오차를 감소시킬 수 있었다. 모의 실험 결과 기존의 블록정합기법(BMA)에 비해 최대 75%의 계산량이 감소하였으며, PSNR 측면에서도 0.3dB이상 개선되었다.

• Proceedings of the IEEK Conference
• /
• 2003.11a
• /
• pp.15-18
• /
• 2003

This paper proposes a color matching 3D look-up table simplifying the complex color matching procedure between a monitor and a mobile display device. In order to perform color matching, it is necessary to process color of image in the device independent color space like CIEXYZ or CIELAB. We improved the S-curve model to have smaller characterization error than tolerance error. Also, as a result of the experiments, we concluded that the color matching look-up table with 64(4$\times$4$\times$4) is the smallest size allowing characterization error to be acceptable.

• Journal of the Korean housing association
• /
• v.15 no.5
• /
• pp.33-41
• /
• 2004

This study examined the effect of the main color of apartment building as background color on the preference for residential streetscape in the relation with surrounding environment of streetscape with its focus on the color of apartment building outer wall. To research a visual evaluation structure, this study aimed to understand its characteristics through quantitative assay and to provide more scientific and specific data about improvement direction. The results suggested that the current brightness and chroma of main color of apartment building was high and low respectively which was advisable. On the other hand, in the color, when the components of the whole streetscape included buildings or soundproofing walls, a streetscape image needed to be improved though the color scheme of 4-distance color difference.

• Journal of Biomedical Engineering Research
• /
• v.24 no.2
• /
• pp.61-68
• /
• 2003

This paper presents a quantitative analysis method for fall in sick times of the cerebral infarction patients using three types of magnetic resonance image, which play an important role in deciding method of medical treatment. For this object, image characteristics obtained by three radiographic methods of MRI and their relation were analyzed by means of object centered hierarchical Planning method. This methode presents an approach to the knowledge based processes for image interpretation and analysis. To compare three type of MRI. a multiple warping algorithm and affine transform method performed for image matching. Then each fall in sick times level of cerebral infarction was quantified and pseudo-color mapping performed by comparing gray level value one another according to Previously obtained hand maid data. The result of this study was compared to a medical doctors decision.