Abstract: Provided is a method and apparatus for determining whether an input mage is a film image. The method includes (a) receiving a predetermined number of similarity values of two adjacent fields of the same kind from an image having interlaced fields, (b) classifying the received similarity values into a first group and a second group, (c) converting the similarity values classified in the first group and the second group into values different from each other, and (d) determining whether the image is a film image according to a period of the converted values. Since input similarity values are classified using a grouping, a film image can be detected without setting a threshold value.

Abstract: Provided are a method and an apparatus for encoding and decoding a color image. The method of encoding a color image includes generating a color transformation function for color format transformation for each block of the color image, performing color transformation on each block of the color image using the generated color transformation function, and performing encoding on each block of the color-transformed image.

Abstract: Provided are an image encoding/decoding method and apparatus, in which one of a plurality of color component images is predicted from a different color component image reconstructed using a correlation between the plurality of color component images. Using a reconstructed image of a first color component image selected from among the plurality of color component images forming a single color image, the other color component images are predicted.

Abstract: Image residue encoding and decoding methods and apparatuses are provided. In this method, a residue of a color component image is predicted from another color component image using a correlation between residues of the color component images, wherein the residues correspond to differences between input images and prediction images of the respective color component images constituting a single image, so that the encoding efficiency is improved.

Abstract: An image encoding/decoding method and apparatus, in which at least one of a plurality of color component images except a first color component image is predicted from motion estimation information or a reconstructed color component image of the first color component images using correlation among the plurality of color component images. The image encoding method includes performing predictive-encoding on the first color component image among the plurality of color component images forming a single image using a general encoding method, and performing motion estimation and compensation on the at least one of the other color component images or predicting the at least one of the other color component images using a reconstructed first color component image.

Abstract: A method and an apparatus adaptively encode a motion image based on temporal and/or spatial complexity. In the method, encoding is performed with different temporal and spatial resolutions at frame rates based on the temporal and/or spatial complexity of an input image so that image data is stored with high efficiency. The method includes calculating a spatial complexity of input image data, determining a resolution by comparing the calculated spatial complexity with a predetermined threshold, and converting the resolution of the input image data based on the resolution.

Abstract: An image encoding/decoding method and apparatus are provided, in which one of color component images forming an image is predicted from a different color component image using a correlation between the color component images. A first color component image selected from the color component images is encoded by intra prediction, and the other color component images are predicted using the reconstructed first color component image. Therefore, color distortion, which may occur when transforming an image color format to another color format, is prevented, thereby improving encoding efficiency.

Abstract: Provided is a method of and apparatus for video intraprediction encoding/decoding. The method of video intraprediction encoding includes dividing pixels of an input block into a plurality of groups, performing intraprediction encoding on pixels of a first group among the plurality of groups using pixels of a previously processed neighbor block, reconstructing the intraprediction-encoded pixels of the first group, determining a directivity of each pixel of the remaining groups using the reconstructed pixels of the first group and reconstructed pixels of previously processed other groups, and performing predictive encoding on the pixels of the remaining groups using the reconstructed pixels of the first group and the reconstructed pixels of the previously processed other groups according to the determined directivities and sequentially processing the pixels of the remaining groups in units of a group according to a predetermined order.

Abstract: A three-dimensional de-interlacing method and apparatus for converting an interlaced scan format image into a progressive scan format image by performing low pass filtering on respective predetermined pixels of a current frame and a previous frame and determining pixel motion index values by comparing a threshold value to a difference value between the respective filtered pixels in a current field in one of the current and previous frames and corresponding respective filtered pixels in preceding and succeeding fields to the current field and in the current and previous frames. A motion mode of a pixel is determined based upon the determined motion index values of temporally and spatially adjacent pixels to the pixel. A spatial interpolation or temporal interpolation on the subjected pixel is selected depending on the determined motion mode.

Abstract: An apparatus and method of motion estimation and mode decision includes a candidate vector group generation unit generating a candidate vector group including a motion vector of an adjacent image crossing a first macro block, where the first macro block is a macro block of an image before scaling, and the first macro block and the adjacent image exist in a same sub-group of a picture (sub-GOP). A motion vector estimation unit estimates a base vector of a second macro block from the motion vector and the candidate vector group of the first macro block overlapped with the second macro block, where the second macro block is a macro block of an image after scaling. A mode decision unit determines a mode of the second macro block from the estimated base vector and a mode of the first macro block.

Abstract: Provided are a method and an apparatus for video encoding/decoding based on an orthogonal transform and vector quantization.

Abstract: A directional interpolation method and a video encoding/decoding apparatus and method using the directional interpolation method. The directional interpolation method includes selecting one of a plurality of directional interpolation modes for a predetermined-size block based on the characteristics of input image data, performing directional interpolation on the predetermined-size block based on the selected directional interpolation mode, and generating mode information indicating the selected directional interpolation mode.

Abstract: A de-interlacing method and apparatus, and a video decoder and a reproducing apparatus using the de-interlacing method or apparatus are provided. The de-interlacing method includes the steps of: (a) determining an interpolation direction based on a plurality of left and right pixels in left and right pixel columns located at left and right sides of the to-be-interpolated pixel, respectively; and (b) obtaining an interpolated pixel value by performing an interpolation process in a determined interpolation direction. According to the de-interlacing method, it is possible to improve interpolation performance by easily and effectively detecting an edge located in a near-horizontal direction without increasing calculation amount.

Abstract: A de-interlacing method and apparatus, and a video decoder and a reproducing apparatus using the same are disclosed. The de-interlacing method, for transforming an interlaced format into a progressive format, includes: (a) obtaining a first difference value between at least one pixel of a previous field and at least one pixel of a next field, which are adjacent to a pixel to be interpolated of a current field; (b) obtaining a second difference value between at least one pixel of the current field and at least one pixel of the previous field or the next field, which are adjacent to the pixel to be interpolated; and (d) obtaining a value of the pixel to be interpolated by weighting a spatial interpolation value and a temporal interpolation value of the pixel to be interpolated according to an interpolation mode selected on the basis of the first and second difference values.

Abstract: A method of encoding moving pictures using a plurality of quantization matrices. The method involves selecting one of the plurality of quantization matrices in consideration of an at least one characteristics of an input image; transforming the input image; and quantizing the transformed input image using the selected quantization matrix.

Abstract: A method of and apparatus for predicting a direct current (DC) coefficient in a transform domain are provided. The method of predicting a DC coefficient of a transform block in video encoding includes calculating a first representative value of pixel values of pixels in the bottom-most row of a neighboring block located above a current block and a second representative value of pixel values of pixels in the right-most column of a neighboring block located to the left of the current block and comparing the first representative value and the second representative value with a predetermined reference value obtained from a block located above and to the left of the current block and selecting a DC coefficient predictor for prediction of the DC coefficient of the current block according to the result of the comparison.

Abstract: In a method of adaptively encoding input image data of a motion image in accordance with a temporal complexity of the motion image, and an apparatus therefore, the temporal complexity of the input image data is calculated. Next, an original frame rate of the input image data is converted into a converted frame rate based on the calculated temporal complexity. Thereafter, the input image data whose frame rate has been converted is encoded, and the encoding data of the encoded image data is controlled so that the encoded image data has information on the converted frame rate. Accordingly, the input image data is encoded at different frame rates in accordance with the temporal complexity of the input image data. Consequently, the encoded input image data is efficiently stored.

Abstract: A method and apparatus for video intraprediction encoding and decoding are provided. The method includes dividing an input block into at least two areas; performing intraprediction on pixels of a first area using pixels of a neighboring block; determining spatial characteristics of pixels of the first area around a pixel of a second area, and determining reference pixels of the first area for prediction of the pixel of the second area based on the spatial characteristics; and predicting the pixel of the second area based on the determined reference pixels of the first area. The apparatus includes a block division unit which divides a block into at least two areas; an intraprediction unit which performs intraprediction; and an interpolation unit which determines spatial characteristics of pixels of the first area, determines reference pixels, and predicts the pixel of the second area based on the reference pixels of the first area.

Abstract: A method and apparatus for video intraprediction encoding and decoding are provided. The encoding method includes dividing an input block into at least first and second areas; performing intraprediction-encoding on pixels of the first area; reconstructing the intraprediction-encoded pixels; and predicting pixels of the second area using the intraprediction-encoded pixels of the first area according to a prediction mode of a plurality of prediction modes. The decoding method includes receiving a bitstream comprising data for pixels of a first area and direction information; determining an intraprediction mode for a current block; performing intraprediction-decoding on pixels of the first area; and predicting the pixels of a second area using the received direction information and the intraprediction-decoded pixels for the first area.

Abstract: A method, a computer readable storage, and an apparatus estimate a motion of a moving image and comprising a process of adjusting a number of search points per frame by adaptively updating a threshold value per frame to regularly maintain fixed a computational complexity of a video encoder irrespective of characteristics of the moving image.