Electronics and Telecommunications Research Institute

Kookmin University

Kyung Ae Moon

Jin Soo Choi

Se Yoon Jeong

Jin Woo Hong

Won-Sik Cheong

Donghyung Kim

Jin Woong Kim

Soo Hyun Lee

Myung Joon Kim

Hyun Eui Kim

Tae One Kim

Suk Hee Cho

Sung Hoon Kim

Won Sik Cheong

Dong Wook Kang

Weon Geun Oh

Kyeong Hoon Jung

Jin Ho Kim

Eun Young Chang

Hyon Gon Choo

Su Young Chi

Ho Wook Jang

Jae Han Kim

Je Ho Nam

Dong Hyung Kim

Joong Ki Park

Young Sup Hwang

Min Sik Park

Youngha Hwang

Kiryung Lee

Dae Geun Jang

Young Ha Hwang

Eun Young Jang

Provided is a method and an apparatus for correcting a distortion of a three-dimensional (3D) hologram, in which the method is performed by the apparatus and includes generating a sliced two-dimensional (2D) section of a hologram by slicing the hologram while performing translation in an optical axis direction, obtaining a sharp sliced image of the hologram from a sequence of images of generated sliced 2D sections using a focusing function of a camera, and analyzing a distortion of the obtained sliced image, and using such a method and apparatus may enable correction of a distortion of a 3D hologram independently from a display structure.

Method and apparatus for correcting distortion of 3D hologram

Disclosed is an apparatus and method for digital holographic table top display. The digital holographic table top display apparatus includes: a camera array configured to capture a plurality of channel images in an omni-directional range from a table by using a plurality of cameras; a controller configured to detect an observer from the plurality of channel images and to track a position of pupils of the observer in at least one channel image from which the observer is detected; and a display configured to reproduce a digital holographic image in a three-dimensional (3D) space according to the tracked position of the pupils.

Apparatus and method for digital holographic table top display

Provided is a hologram generation method including receiving three-dimensional (3D) data information, determining a first projection position onto which the 3D data information is projected on a hologram plane corresponding to a first spatial light modulator (SLM), and a second projection position onto which the 3D data information is projected on a hologram plane corresponding to a second SLM, generating a first Fresnel zone plate (FZP) pattern corresponding to the first projection position, and determining the first FZP pattern to be an FZP pattern corresponding to the second projection position.

Hologram generation method and apparatus

The present invention discloses a holographic display apparatus including a light irradiating unit configured to irradiate light using an optical fiber array backlight, a spatial light modulator (SLM) configured to perform modulating the irradiated light, a lens configured to irradiate hologram images based on the modulated light, a pupil tracking unit configured to acquire location of an observer's pupil by pupil tracking, and a hologram generating unit configured to generate parallax hologram images that correspond to the location of pupil.

Holographic display method and apparatus using optical fiber array backlight for portable device

An apparatus and a method for measuring quality of a holographic image are disclosed. The apparatus for measuring the quality of the holographic image may include an obtaining unit to obtain a hologram, a reconstruction unit to reconstruct a three-dimensional (3D) holographic image by irradiating the hologram with a light source, a measuring unit to measure depth of the reconstructed holographic image, and an analysis unit to analyze depth representation quality of the holographic image base on the measured depth of the holographic image.

Apparatus and method for measuring quality of holographic image

A method and apparatus for determining an image compression format of a 3-dimensional television (3DTV). The method may include encoding a high-quality image and transmitting the encoded high-quality image through a first channel, determining an image compression format in which a resolution of the encoded low-quality image is higher than or equal to a reference value in comparison to the high-quality image, and encoding the low-quality image according to the determined image compression format and transmitting, the encoded low-quality image through a second channel.

Method and apparatus for determining a video compression standard in a 3DTV service

An apparatus for coding an image is provided to effectively code the image. The apparatus for coding the image includes an input image segmentation unit to segment an input image into a plurality of image blocks including a first image block and a second image block. The apparatus also includes a waveform information generation unit to select a plurality of reference pixels from among pixels included in the first image block, generate first waveform information about the first image block based on a pixel value difference between the selected plurality of reference pixels, and generate second waveform information about the second image block based on a pixel value difference between the pixels included in the second image block. The apparatus also includes a coding unit to code an image included in the second image block based on the first waveform information and the second waveform information.

Apparatus for coding or decoding intra image based on line information of reference image block

A video encoding method and apparatus are provided. The video encoding method includes determining whether a current block includes an affine-transformation object having an affine transformation; if the current block includes an affine-transformation object, generating a prediction block by performing affine transformation-based motion compensation on the current block in consideration of an affine transformation of the affine-transformation object; and if the current block does not include any affine-transformation object, generating a prediction block by performing motion vector-based motion compensation on the current block using a motion vector of the current block. Therefore, it is possible to achieve high video encoding/decoding efficiency even when a block to be encoded or decoded includes an affine transformation.

Method and apparatus for encoding and decoding video signal using motion compensation based on affine transformation

Disclosed a method of designing a watermark having the power spectral density optimized so that the detection performance can be improved by employing the whitening filtered detection after the Wiener attack. The power spectral density of the watermark is designed using an optimization method that can improve the entire detection performance by reflecting the gain of the whitening filter after the Wiener attack. A higher detection gain is obtained using the whitening filter after the Wiener attack, and the expected value of the difference between test statistics of the two hypotheses that the watermark exists and the watermark does not exist, respectively, is maximized to optimize the detection performance. Regarding the expected value of the difference between the test statistics as an objective function, the power spectral density of the watermark, which corresponds to a maximum differentiated value of the power spectral density of the watermark using the Lagrange multiplier method, is obtained.

Method of designing watermark in consideration of wiener attack and whitening filtered detection

Disclosed is a method for embedding and extracting a spatial domain blind watermark using a sample expansion. The sample expansion method using a sample expansion coefficient is introduced to basically improve a common disadvantage of the conventional watermarking method based on the patchwork method, for instance, the watermark is not robust against a compression attack such as JPEG. By applying the sample expansion to a sample group, the embedded watermark comes to contain a low frequency component more larger than ever, so that radio frequency component decreases as much. Thus, although the radio frequency component of the watermark is damaged by the image compression such as JPEG, it is possible to relatively reduce the damage of the watermark. Also, an adaptive watermark embedding method can be considered such that the embedded watermark value is proportional to an average value of the pixel. In order to overcome non-robustness that is a common disadvantage of the conventional methods based on the conventional patchwork method or the conventional modified patchwork method, not a single pixel but sample-expanded pixel is chosen, and there is proposed a spatial domain blind watermarking method using a watermark value that is proportional to an average value of pixel every tile.

Method for embedding and extracting a spatial domain blind watermark using sample expansion

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Daejeon, South Korea

Kyung Ae Moon