Abstract: A deblock method for processing at least one image including a plurality of pixels. The method comprises the step of determining a shift amount of block boundary by pixel data differences between adjacent pixels and thereby determining block boundaries between macroblocks in the image, and the step of optionally performing a deblock process on the block boundaries.

Abstract: According to one embodiment, an MPEG noise reduction processing unit which performs a process of reducing a mosquito noise to a received video signal can be controlled in a setting state corresponding to a desired item selected on the setting screen in which the plural items to be set are displayed as an option.

Abstract: Estimation of a 3D layout of roads and paths traveled by pedestrians is achieved by observing the pedestrians and estimating road parameters from the pedestrian's size and position in a sequence of video frames. The system includes a foreground object detection unit to analyze video frames of a 3D scene and detect objects and object positions in video frames, an object scale prediction unit to estimate 3D transformation parameters for the objects and to predict heights of the objects based at least in part on the parameters, and a road map detection unit to estimate road boundaries of the 3D scene using the object positions to generate the road map.

Abstract: Two pairs of deblock instructions for performing deblock filtering on a horizontal row of pixels according to the H.264 (MPEG 4 part 10) and VC1 video codec algorithms. The first instruction of each pair has three 128-bit operands comprising the 16-bit components of a horizontal line of 8 pixels crossing a vertical block edge between pixels 4 and 5 in a YUV image, a series of filter threshold parameters, and a 128-bit destination operand for storing the output of the first instruction. The second instruction of each pair accepts the same 16-bit components as its first input, the output of the first instruction as its second input and a destination operand for storing an output of the second instruction as its third input. The instruction pairs are intended for use with the H.264 or VC1 video codecs respectively.

Abstract: Systems and methods are presented for improving the quality of an image as perceived by the Human Vision System by smoothing block artifacts in an image. In one embodiment, smoothing is accomplished by identifying target pixels to be smoothed and then replacing the pixel values of the target pixels with values derived from statistically similar neighboring pixels. The statistically similar neighboring pixels are chosen based on specific measurement criteria from within a region identified to contain such neighbors.

Abstract: Reduction in the blockiness of a simulated film grain block can be achieved either by the use of adaptive downscaling or adaptive deblocking filtering to adjust the intensity of the pixels at the block edge in accordance with at least one film grain block parameter, such as film grain size, intensity and texture. Performing such adaptive downscaling or adaptive deblocking filtering achieves improved performance at lower computational cost by avoiding modification of film grain block pixels in lesser affected areas.

Abstract: A system and method for filtering a frame, the method includes: (i) processing, by a processing unit executing instructions, at least one portion of a frame to provide at least one processed frame portion; (ii) performing, by a hardware filter, deblocking filtering of the at least one processed frame portion to provide at least one filtered frame portion; and (ii) storing the at least one filtered frame portion in a memory unit that is accessible by the processing unit; whereas the stage of processing is responsive to previously filtered frame portions.

Abstract: A block distortion reduction apparatus, enabling easy processing by a small-sized circuit configuration and enabling generation of block distortion reduction parameters by any area unit inside a frame, which averages encoding coefficients in a macroblock units to obtain a DCT parameter, calculates a DMV parameter of differential motion vectors by weighting in accordance with the encoding mode of the macroblock unit, and determines a correction value for the block distortion reduction based on these parameters.

Abstract: In order to improve image quality of high compression ratio images, a de-blocking process is performed on decoded image data, and then an edge enhancement process is performed on the de-blocked image data. Performing the edge enhancement process after performing the de-blocking process can improve image quality of high compression ratio images.

Abstract: An apparatus and method for compensating images in a display device is disclosed. Distortion ratios of image blocks are calculated based on a gray value difference between each of a plurality of pairs of pixels in the image blocks that face each other at a boundary between the image blocks. Compensation parameters are set based on the calculated block distortion ratios. Distortion compensation values of the image blocks are calculated based on the gray value difference and the set compensation parameters. The image blocks are then compensated according to the calculated distortion compensation values.

Abstract: A data processing apparatus capable of performing processing in units of block data by using processing results of other block data in a short time is provided, wherein a deblocking filter performs horizontal filtering processing and vertical filtering processing on first block data and second block data obtained by dividing restructured picture data into two in parallel by adjusting their dependency relation.

Abstract: A block noise reduction system and method which may determine a feature value of a local texture at each location of input pixel, may selectively determine 1D filtering mode or 2D filtering mode as a filtering mode based on the determined feature value, and may perform filtering to preserve an edge according to the determined filtering mode.

Abstract: An estimation system provides quality measure of a given image for image/video applications to determine if the image needs to be enhanced or not. The system systemically measures the image quality by estimating quantization parameter of the compressed digital image. This allows estimating the image quantization parameter effectively in the pixel domain. Because block artifact are caused by image compression transforms, especially in flat image region, the estimation system first detects the suspicious regions of the image for the block artifacts by calculating a variance for each location in the image. Next, noise power is computed by using the detected regions. Then, the estimated noise power is compared with the statistical model to calculate the quantization parameter that is used in the encoder side when the input image is compressed. Finally, a quantization parameter is used as a quality measure of the input image.

Abstract: A method for removing blocking artifacts from moving and still pictures, comprising classifying horizontal and vertical boundaries in each picture as blocky or non-blocky; for each blocky boundary, defining an adaptive, picture contentdependent, one-dimensional filtered pixels region of interest (ROI) that crosses the boundary and is bound at each of its ends by a bounding pixel; defining a finite filter having a length correlated with the length of the ROI; defining a filtering pixels expansion that uniquely determines the padding values of the finite length filtered pixels ROI for the finite length filtering; and filtering the ROI pixels using the finite filter and the filtering expansion.

Abstract: There is provided an image coding apparatus including a mode selection unit arranged to select an input image type, an input unit arranged to input image data in accordance with an output of the mode selection unit, an image size determination unit arranged to determine an image size of the image data input by the input unit, a block size determination unit arranged to determine a block size of a block in accordance with the image size determined by the image size determination unit; and a block construction unit arranged to divide the image data input by the input unit into blocks of the block size determined by the block size determination unit.

Abstract: There is provided with an image coding method including: splitting an image into a plurality of block images each having plural pixels; performing a Discrete Cosine Transform (DCT) processing on the block image to calculate DCT coefficients from the block image; determining whether the block image is in a flat state or non-flat state depending on the DCT coefficients calculated from the block image; specifying as quantization step sizes for first DCT coefficients which are DCT coefficients equivalent to one-dimensional DCT coefficient out of the calculated DCT coefficients, adjusting step sizes equal to or smaller than values of the first DCT coefficients and as quantization step sizes for second DCT coefficients other than the first DCT coefficients out of the calculated DCT coefficients, standard step sizes given beforehand, when the block image is in the flat state; and quantizing the calculated DCT coefficients with respective quantization step sizes specified.

Abstract: A printing apparatus comprises a processor comprising registers, and a memory configured to store image data. The processor is configured to load portions of the image data into the registers and perform toner explosion compensation on the portions of the image data loaded in the registers, excluding image data loaded in boundary positions in the registers.

Abstract: Disclosed herein is an image processing method for producing enhanced halftone edges, particularly suited to those edges which only lie upon the background as apposed to those edges which abut other halftone screens. It utilizes a step of defining border pixels and a step of halftoning those border pixels in a different manner than the halftoning applied to the interior region of the tint or image segment. The preferred halftone for the border pixels will be related to the interior halftone by some number of common spatial frequency harmonics.

Abstract: An image processing device includes: an estimating module configured to estimate boundaries of blocks in an input image; a characteristic value calculating module configured to calculate a characteristic value of a subject pixel group having constituent pixels including a pixel in the frame and at least one pixel that is adjacent to the pixel by calculating a degree of pixel value dispersion between the constituent pixels of the subject pixel group if all the constituent pixels belong to the same block; an strength value calculating module configured to calculate, from the characteristic value, a strength value to be used in performing pixel value smoothing; and a smoothing module configured to perform the pixel value smoothing according to the strength value.

Abstract: Block noises at block boundaries are removed, but when a contour line in the original image matches a block boundary, the degree of block noise removal is adjusted and image quality is improved. An adaptive filter has a step of calculating the weight of pixels near the block boundary by a high-pass filter, and a step of determining an adjusted value for the pixels near the block boundary based on the weight. The pixel values near the block boundary are adjusted and block noises are removed. A low-pass filter is applied to pixels near the block boundary to determine a filtered value. The adjusted values of the pixels near the block boundary are determined by obtaining a weighted sum of the original pixel value and the filtered value.

Abstract: A deblocking method, for removing blocking artifacts comprises selecting a plurality of first pixels according to a bandwidth of a memory device, wherein the first pixels are uniformly distributed at two sides of a block boundary; calculating a first value according to the first pixels stored in the memory device; determining a computing mode according to the first value and a first predetermined value; generating a plurality of second pixels according to the first pixels and the computing mode; and replacing the first pixels stored in the memory device with the second pixels.

Abstract: A pixel boundary difference detector detects a pixel boundary difference across a pixel boundary on the basis of a difference value between pixel values of adjacent pixels across the pixel boundary on a picture plane of an input image frame, and a predicted pixel value on the pixel boundary predicted from at least a plurality of pixels on one side of the pixel boundary, an accumulator accumulates the pixel boundary differences for one image frame, and a block noise detector detects a block noise on the basis of a result of the accumulation. The accuracy of block noise detection is improved, the effect of block noise reduction is improved, and the picture quality is improved.

Abstract: High-frequency noise is generated that approximates the appearance of traditional “film grain” for a digital video signal. By adding a relatively small amount of film grain noise, the video can be made to look more natural and more pleasing to the human viewer. The digital film grain generation can be used to mask unnatural smooth artifacts in digital video such as “blockiness” and “contouring” in the case of compressed video and/or used to provide visual enhancements or special effects to any digital video stream. The digital film grain generator can control grain size and the amount of film grain to be added.

Abstract: A method is provided for block artifact detection and block artifact determination using multiple features in coded images and video. A method includes identifying a plurality of overlapping blocks in a picture with respect to a current block. Each of the plurality of overlapping blocks covers a portion of the current block and a portion of an adjacent block. The method further includes transforming at least one of the plurality of overlapping blocks into respective coefficients corresponding to at least one of a luminance component and a chrominance component. The method also includes identifying a block artifact for the at least one of the plurality of overlapping blocks when coefficients corresponding to the at least one of the plurality of overlapping blocks are larger than a predefined value.

Abstract: In a method, apparatus and integrated circuit for improving image sharpness, the method includes the following steps: (a) labeling each of pixels in an image as one of an edge/texture type and a non-edge/texture type; (b) classifying each of the pixels that are labeled as the edge/texture type into one of a border point type, a transition point type, and a peak point type; and (c) using a shrinking/expanding filter to filter the pixels of the border point type, and subsequently using a high boost filter to first filter the pixels of the peak point type and then filter the pixels of the transition point type to sharpen the image.

Abstract: The present invention is directed to systems and methods in which, for a given amount of data required to represent a compressed video signal, the quality of the uncompressed displayed real-time video, as perceived by a typical human viewer, is improved. Systems and methods herein achieve this improvement by attenuating the appearance of blocks without necessarily having a priori knowledge of their locations. The methods described herein attenuate the appearance of these blocks such that the quality of the resultant real-time video, as perceived by the HVS, is improved.

Abstract: A method of removing blocking artifacts from block-coded digital images and an image reproducing apparatus using the same remove blocking artifacts from a block-coded digital image. The method includes adjusting filtering offsets on a block-by-block basis using motion vector (MV) and quantization parameter (QP) values; and performing deblocking filtering to remove the blocking artifacts from a decoded digital image using the adjusted filtering offsets. Accordingly, since the filtering offsets may be adaptively adjusted on a block-by-block basis to fit image characteristics, the blocking artifacts may be efficiently removed, thus, improving image quality.

Abstract: A method is for filtering tomographic 3D images of an examination object. The examination object is imaged by using a volume model that divides the volume of the examination object into a multiplicity of three-dimensional image voxels with individual image values, wherein the image value of each voxel reproduces an object-specific property of the examination object in this volume. After the reconstruction of the total volume for each voxel, variances are calculated in a prescribed region or radius R in order to determine contrast jumps and their spatial orientation with their tangential planes T. The image values in the tangential plane T are filtered with a two-dimensional convolution, and subsequently the original voxel data are mixed in weighted fashion with the filtered voxel data.

Abstract: The invention proposes a method (FIG. 2) and respective devices (FIG. 2) and software for an algorithm to detect and remove ringing artefacts and mosquito noise in decompressed pictures and video. The proposed idea is based on the observation that ringing is spatially localized within a block, which contains at least a part of an object edge, in particular a strong object edge. Blocks affected by ringing are detected by analyzing (1) a block grid position, location (2) of an object edge and by comparing (7) local spatial activities (Act af, Act nor) of adjacent blocks, i.e. affected blocks and nor) not-affected blocks.

Abstract: Systems and methods of reducing artifacts in compressed images are described. In one aspect, spatially-shifted forward transforms of the input image are computed to generate respective sets of forward transform coefficients. Nonlinear transforms are applied to the forward transform coefficients of each set. Inverse transforms of the sets of nonlinearly transformed forward transform coefficients are computed to generate respective intermediate images. Respective measures of local spatial intensity variability are computed for pixels of each of the intermediate images. An output image is computed with pixel values computed based at least in part on the computed measures of local spatial intensity variability.

Abstract: A system and method that optimizes a de-blocking filter process using local buffers. The local buffers may be off of the memory unit in which image data may be stored. The data associated with the image may be loaded into the local buffers. The data may be then fed into a filter, where the de-blocking filter process is executed, and the filtered data may be loaded back into the local buffers. The filtered data may then be written back to its original location in the memory.

Abstract: The present invention relates to an image processing technique, and in particular to a method for restoring a compressed image by using a hybrid motion compensation discrete cosine transform (hybrid MC/DCT) mechanism, including: a step of defining a smoothing functional having a smoothing degree of an image and reliability for an original image by pixels having an identical property in image block units; and a step of computing a restored image by performing a gradient operation on the smoothing functional in regard to the original image, thereby preventing the blocking artifacts and the ringing effects in regard to the pixels having an identical property in image blocks. In one embodiment, the method includes obtaining a pixel value in a current block and at least one adjacent pixel value. A type of the current block is one of an intra-coded type and inter-coded type. A smoothing value of the current block is determined based on the obtained pixel value in the current block and the adjacent pixel value.

Abstract: A video encoding method and apparatus is shown wherein image information is represented as a plurality of pixels, the pixels are organized into blocks, pixels transposition is performed on image information at the boundaries of the blocks, the blocks are transform coded and quantized. Pixel transposition involves transposition of alternate pixels at the boundaries of blocks with pixels of neighboring blocks found in a pre-determined direction. The pre-determined direction may be fixed by a system or may be applied on an image by image basis. In the event that the pre-determined direction is not established by a system, a pixel transposition circuit includes a transposition keyword in the output bit stream which is used by a decoded to determine the direction of pixel transposition.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a pixel of an image is filtered according to a filtering methodology. The filtering methodology includes selecting a filtering mask based on a position of a pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a filtering mask is selected based on a position of a pixel to be filtered. The filtering mask includes the pixel to be filtered and at least one candidate pixel.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In an embodiment, the filtering unit is configured to select a filtering mask based on a position of a pixel to be filtered. The filtering mask includes the pixel to be filtered and at least one candidate pixel.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In one embodiment of the present invention, a pixel of an image is filtered according to a filtering methodology.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a pixel of an image is filtered according to a filtering methodology. The filtering methodology includes selecting at least four pixels of successive pixels according to a position of a pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In one embodiment, the filtering unit is configured to select at least four pixels of successive pixels according to a position of a pixel to be filtered. The selected at least four pixels include the pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In an embodiment, the filtering unit is configured to select at least four pixels of successive pixels according to a position of a pixel to be filtered. The four pixels include the pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the apparatus, a pixel of an image is filtered by a filtering unit. The filtering unit is configured to select at least four pixels of successive pixels according to a position of a pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a pixel of an image is filtered according to a filtering methodology. The filtering methodology includes selecting at least four pixels of successive pixels according to a position of a pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In one embodiment, a pixel of an image is filtered according to a filtering methodology.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a pixel of an image is filtered according to a filtering methodology.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. The filtering unit is configured to select at least one candidate pixel to be associated with an averaging operation, and compare a difference between the pixel to be filtered and the candidate pixel with a threshold.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In one embodiment, the apparatus includes a filtering unit configured to filter a pixel of an image.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In an embodiment of the present invention, a pixel of an image is filtered according to a filtering methodology.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In an embodiment, the filtering unit is configured to select at least four pixels of successive pixels according to a position of a pixel to be filtered.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In an embodiment, the filtering unit is configured to select a filtering mask based on a position of a pixel to be filtered. The filtering mask includes the pixel to be filtered and at least one candidate pixel.

Abstract: A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect. In the method, a pixel of an image is filtered according to a filtering methodology. The filtering methodology includes selecting at least four pixels of successive pixels according to a position of a pixel to be filtered.