Abstract: A method of deblocking an input signal is disclosed. The method generally includes the steps of (A) calculating a plurality of transform coefficients corresponding to each of a plurality of blocks in the input signal at baseband, (B) calculating a plurality of quantization parameters based on the transform coefficients, at least one of the quantization parameters corresponding to each respective one of the blocks and (C) generating an output signal by deblocking the input signal based on the quantization parameters.

Abstract: An amount-of-compressed-data control method applicable to image data compression processing for compressing an amount of data is disclosed. The method includes the steps of: performing quantization by: dividing one digital image into multiple blocks each having n×n pixels; performing orthogonal transform on each block; and dividing n×n conversion coefficients resulting from the conversion by each threshold value of a quantization matrix including n×n threshold values each resulting from the multiplication of a predetermined coefficient S (where S is a positive real number); and variable-length encoding the quantized data.

Abstract: A method, system, and apparatus are directed towards computing minimum mean squared error (MMSE) predictive-transform (PT) source coding integrated with subband compression to further improve the performance of low bit rate MMSE PT source coders. A desirable byproduct of the advanced scheme is that the incorporation of joint optimum prediction and transformation from subband to subband is ideally suited to its integration with JPEG2000 to yield even higher compression levels while producing an outstanding objective as well as subjective visual performance.

Abstract: An image information decoding method for decoding compressed image information which has been coded via a process including dividing an input image signal into blocks, performing an orthogonal transform on the blocks on a block-by-block basis, and quantizing resultant orthogonal transform coefficients. The decoding process includes performing dequantization such that a quantization parameter is weighted by an addition operation, and the dequantization is performed on each chroma components of the quantized coefficients using said weighted quantization parameter, and performing an inverse orthogonal transform.

Abstract: The present invention relates to an image processing method and apparatus for processing compressed image generated by segmenting image data into a plurality of MCUs and using a compression method in which a frequency transformation is applied to each MCU. In a case that the compressed image is decoded, each MCU is classified according to the frequency coefficients therein, and color separated data is generated for each MCU based on the decoded data resulting from the decoding and the results of the MCU classification.

Abstract: In a method of compressing image data which include a plurality of pixel values which are associated with a respective pixel, the pixel values are coded for at least some pixels in accordance with the following steps: determining an estimated pixel value of the respective pixel in dependence on the pixel value of at least one predetermined other pixel while using an estimation rule; and forming a difference value of the respective pixel which corresponds to a predefined relation between the pixel value and the estimated pixel value of the respective pixel and quantization of the difference value in accordance with a difference value quantization rule. The quantized difference values of the pixels are compressed in accordance with a compression rule.

Abstract: An image information decoding method for decoding compressed image information in an image decoding apparatus, which has been coded via a process including dividing an input image signal into blocks, performing an orthogonal transform on the blocks on a block-by-block basis, and quantizing resultant orthogonal transform coefficients. The decoding process includes performing, in a dequantization unit in the image decoding apparatus, dequantization such that a quantization parameter is weighted by an addition operation that adds the weight by addition, and the dequantization is performed on each chroma and luma component of the quantized coefficients using quantization step sizes, said luma component being weighted by the quantization parameter; and performing, in a transform unit in the image decoding apparatus, an inverse orthogonal transform.

Abstract: The invention relates to a method of locally adjusting a quantization step for each region of an image with respect to a setpoint quantization step. The method comprises the steps of: assigning, to said region of interest, a first quantization step, lower than or equal to said setpoint quantization step; determining a second quantization step higher than or equal to said setpoint quantization step and lower than or equal to a third quantization step such that the number of bits required by the region of interest is lower than the number of bits saved on the potential masking region; and assigning, when such a second quantization step exists, said second quantization step to said potential masking region, otherwise assigning said third quantization step to said potential masking region.

Abstract: Generating an error from an error metric quantifying differences between reference objects representing characters and representations of the reference objects. One embodiment includes a method which includes accessing a reference object representing a character. One or more reference object characteristics are quantified. The reference object characteristics are related to character structural and color information of at least a portion of the reference object to generate a reference object metric. A representation object of the reference object is accessed. One or more representation object characteristics are quantified to create a representation object metric. The representation object characteristics are related to character structural and color information of a portion of the representation object of the reference object corresponding to the portion of the reference object. An error is calculated based on a difference between the reference object metric and the representation object metric.

Abstract: The invention relates to a method of locally adjusting a quantization step for each region of an image in a sequence of n images. The method comprises the following steps; calculating, for each image of the sequence, a first difference of bits saved on the potential masking region when quantizing it with a first quantization step and a second difference of bits required by the region of interest when quantizing it with a second quantization step; and in each image of the sequence, assigning to the potential masking region the first quantization step and if the sum of the n first differences of bits is higher than the sum of the n second differences of bits assigning said second quantization step to said region of interest and otherwise assigning a third quantization step such that the sum of said n first differences of bits is distributed between the regions of interest according to a reconstruction quality criterion.

Abstract: In an image encoder, a first quantization section which is selected when normal image quality is required performs quantization by dividing a wavelet transformation coefficient by a quantization step size and by thereafter rounding down a fraction thereof. On the other side, a second quantization section which is selected when high image quality is required performs quantization by dividing a wavelet transformation coefficient by a quantization step size, by adding 0.5 to the addition result, and by thereafter rounding down a fraction thereof. Therefore, the width of a dead zone where coefficients are quantized to a value of 0 is narrower than that in the first quantization section, and higher image quality is obtained accordingly.

Abstract: A video encoder identifies one or more AC coefficients of each of plural blocks in the picture. The encoder identifies a threshold quantization step size such that the identified AC coefficient(s) of each of the plural blocks are nonzero after quantization according to the threshold quantization step size. The threshold quantization step size is such that quantization according to the next higher quantization step size would result in at least one of the identified AC coefficient(s) of at least one of the plural blocks being zero. For example, identifying the threshold quantization step size comprises identifying n top AC coefficients in each of four blocks of a macroblock, determining the smallest AC coefficient among the identified n top AC coefficients of the four blocks, and iteratively evaluating the smallest AC coefficient with respect to candidate quantization step sizes until the threshold quantization step size is identified.

Abstract: An apparatus capable of dividing an m-value image into a plurality of divided images and performing quantization into an n-value image (2?n<m) for each divided image includes a first quantization unit for quantizing a first region in the divided image similarly to a region to be joined, and a second quantization unit for sequentially quantizing a second region in the divided image including the first region. If the second quantization unit quantizes the first region, parameters for the quantization processing is corrected using a quantization result in the first quantization unit such that the quantization result approaches the quantization result in the first quantization unit.

Abstract: A motion image decoding apparatus for generating a prediction signal in blocks is provided with a low-resolution block decoder for generating a low-resolution block with a smaller number of pixels than that of a prediction block by decoding encoded data. The motion image decoding apparatus is further provided with an enhanced block generator for enhancing a low-resolution block generated by a decoded low-resolution block to a block with the same number of pixels as that of the prediction block using a decoded image. Furthermore, the motion image decoding apparatus is provided with a block divider for generating plural small blocks by dividing an enhanced block based on a predetermined division rule and a small block predictor for generating a predicted small block of a small block using a decoded image and the plural small blocks.

Abstract: An image reading device includes a reference member, a reading unit, a first reference value setting unit, a detecting unit, a second reference value setting unit, a determining unit, and a pixel value setting unit. The reading unit obtains image data and reference data. The first reference value setting unit sets a first reference value based on the reference data. The detecting unit detects a usage state of the reading unit. The second reference value setting unit sets a second reference value in accordance with the usage state. If the determining unit determines that the first reference value is in a predetermined condition, the pixel value setting unit sets a pixel value based on the image data and the first reference value; otherwise, the pixel value setting unit sets the pixel value based on the image data and the second reference value.

Abstract: Video encoding methods and video encoders that provide improved performance while reducing power consumption. In one aspect, a video encoding method comprises the steps of outputting a parameter for a slice of a current frame, wherein the slice comprises a plurality of macroblocks, and the parameter comprises an address of a first macroblock of the slice, an address of a search area on a previous frame, a search area corresponding to a current macroblock, and a number of macroblocks comprising the slice; processing the slice by consecutively encoding and decoding each macroblock of the slice in response to the parameter; and outputting an interrupt signal for the current frame, when encoding and decoding for each macroblock of the all slices is consecutively performed so that encoding for the current frame is completed.

Abstract: In uniform superposition of two predictions toward a weighted superposition, such as in coding B frames, weighting is based on reliability of a reference picture used for determination of the prediction. Since there is a relationship between the reliability and the respective quantization parameter, coupling to the quantization parameter that is also known in the receiver also can be effected advantageously.

Abstract: A one-pass picture-layer rate control (RC) method and system for controlling a video encoder: The bit allocation and determination of quantization parameter (QP) in this rate control method and system are based on a Rate-Quantization (R-Q) scale model. The R-Q model is a linear one, wherein the number of bits per picture is in reverse ratio of quantization scale for that picture. A conversion of exponential-based QP to linear-scaled QP is taken in the calculation of complexity model and determination of QP. The conversion is integer-based and is consistent with the quantization array defined in the H.264 standard.

Abstract: An information processing apparatus for encoding image data includes: a rearranging unit for rearranging coefficient data divided for each frequency band in order of executing synthesis processing for synthesizing the coefficient data of multiple sub-bands divided into frequency bands to generate image data for each line block including image data equivalent to the number of lines necessary for generating coefficient data equivalent to one line of the sub-band of the lowest frequency components; a control unit for calculating a new quantization step size at the time of encoding the image data for each coding unit using the ratio between the generated code amount at the time of encoding with a known quantization step size and a target code amount at the time of encoding the image data; and an encoding unit for encoding the coefficient data for each coding unit to generate encoded data using the calculated quantization step size.

Abstract: An embodiment of a method for encoding a source image comprising multiple data units, performed by an image encoding unit, comprises the following steps. A quantized DC coefficient and multiple AC coefficients of a data unit are generated. A value at the (0,0) element of the first data unit is determined according to the quantized DC coefficient. A variable length coding (VLC) stream of the data unit is generated by encoding the determined value and the AC coefficients. An encoded bitstream comprising a restart mark followed by the VLC stream of the data unit is generated. An offset pointing to the beginning of the restart mark of the encoded bitstream is stored in a random access table. A compression image comprising the encoded bitstream and the random access table is generated.

Abstract: A method to determine real time image complexity in video streaming, IPTV and broadcast applications using a statistical model representing channel bandwidth variation and image complexity that considers scene content changes. Available channel bandwidth is distributed unevenly among multiple video streams in proportion to bandwidth variation and image complexity of the broadcast video stream. The distribution of available channel bandwidth is determined based upon an image complexity factor of each video stream as determined from probability matrices considering bandwidth variations and image complexity.

Abstract: A sequence of n coefficients is compressed by determining a cost-determined sequence of n coefficient indices represented by a cost-determined sequence of (run, index derivative) pairs under a given quantization table and run-index derivative coding distribution, wherein each sequence of (run, index derivative) pairs defines a corresponding sequence of coefficient indices such that (i) each index in the corresponding sequence of coefficient indices is a digital number, (ii) the corresponding sequence of coefficient indices includes a plurality of values including a special value, and (iii) each (run, index derivative) pair defines a run value representing a number of consecutive indices of the special value, and an index-based value derived from a value of the index following the number of consecutive indices of the special value.

Abstract: A process for secured distribution of fixed numerical images according to a nominal format resulting from numerical encoding in wavelets, represented by a original stream including a packet relating to organization of a binary sequence that contains at least a block that regroups numerically encoded simple elements according to a mode specified inside the stream and utilized by decoders that are capable of reconstructing or decoding it to be able to correctly display the image including modifying at least one of the simple elements according to at least a substitution operation including extracting the simple element, followed by its replacement by lure data, modifying a principal stream to conform to a nominal format including modified blocks and packets, and by a path that is separate from the principal stream of complementary numerical information and allowing reconstruction of the original stream from calculations, on destination equipment, as a function of the principal stream and the complementary infor

Abstract: A method and system generates and compares fingerprints for videos in a video library. The video fingerprints provide a compact representation of the spatial and sequential characteristics of the video that can be used to quickly and efficiently identify video content. Because the fingerprints are based on spatial and sequential characteristics rather than exact bit sequences, visual content of videos can be effectively compared even when there are small differences between the videos in compression factors, source resolutions, start and stop times, frame rates, and so on. Comparison of video fingerprints can be used, for example, to search for and remove copyright protected videos from a video library. Further, duplicate videos can be detected and discarded in order to preserve storage space.

Abstract: A data compressing method comprises first step in which a data is orthogonally transformed so that an orthogonal transform data is generated. A processing step executed subsequent to the first step is divided into a processing step for an alternate-current component of the orthogonal transform data and a processing step for a direct-current component of the orthogonal transform data. The processing step for the direct-current component includes a second step in which an inverse transform equivalent to a decoding process of the orthogonal transform data is executed on the orthogonal transform data.

Abstract: Bitmap compression for fast searches and updates is provided. Compressing a bitmap includes receiving a bitmap to compress, and reading the bitmap to determine a value of a bit location for all bits in the bitmap. In one embodiment, a compressed bitmap is created by encoding a variable number of bytes to represent a distance between adjacent 1s in the uncompressed bitmap. In another embodiment, a compressed bitmap is created by representing a distance between adjacent 1s in the uncompressed bitmap using a plurality of bits, and encoding a marker word to indicate the number of bits used to represent the distance.

Abstract: Coding processing performed by an image coding device (100) includes: processing (S133) of performing coding by leaving surplus bit(s), when the digit number B of binary data of the difference value between (a) a value of a to-be-coded pixel and (b) a prediction value is smaller than the predetermined bit number M; and processing (S133) of performing coding by using the surplus bit(s), when the digit number B is greater than M and there are the surplus bit(s). Pieces of coded data each having a predetermined coding amount are generated, by performing processing for each of consecutive T pixels so as to perform the coding processing for each of U pixels among the consecutive T pixels (S136).

Abstract: An image coding method for run-length coding (RLC), including quantizing a coefficient string representing a plurality of pixel values to generate a first quantization coefficient string, determining a cutoff quantization coefficient in the first quantization coefficient string, discarding a part of quantization coefficients of the first quantization coefficient string according to the cutoff quantization coefficient, and forming remaining quantization coefficients of the first quantization coefficient string as a second quantization coefficient string, and performing image coding to the second quantization coefficient string with the RLC.

Abstract: An image compression method is used for processing a plurality of pixels of an image. The image compression method includes the steps of receiving N pixels; analyzing the N pixels and generating a content type corresponding to the N pixels; obtaining a quantization parameter and a coding parameter corresponding to the N pixels according to the content type and a currently available buffer space value; obtaining N quantized differences corresponding to the N pixels through a prediction and quantization way according to values of the N pixels and the quantization parameter; and encoding the N quantized differences according to the N quantized differences and the coding parameter.

Abstract: A method and system are introduced that provide dynamic quantizer structures which are configurable during run time. A quantizer configuration and data are stored in a binary format. The dynamic quantizer data is represented as a bitstream, and the bitstream in turn is used as additional input during initialization (or re-initialization/re-configuration) of a speech coder. A configuration header fully specifies the structure and configuration of the dynamic quantizer for each quantized parameter, and the dynamic quantizer data and configurations are fully and dynamically allocated into the speech coder memory. This enables easy re-configuration of a codec associated with the quantizer structures for different scenarios. The use of dynamic quantizer structures in turn enhances compression efficiency of an input signal. The dynamic quantizer structures can also be applied to other compression applications that allow lossy compression.

Abstract: An image data compression device for rapidly compressing the file to a desired capacity is provided. The image data compression device comprising a compression target capacity value storage device for storing compression target capacity value defined in advance; a compression processing information storage device for storing information in the compression processing; a primary compression device for performing a prescribed compression processing on the image data to generate primary compressed image data, and storing the primary compression information representing a compression property during the compression processing in the compression processing information storage device; and a secondary compression device for compressing the primary compressed image data based on the primary compression information stored in the compression processing information storage device and the compression target capacity value stored in the compression target capacity storage device.

Abstract: A method of reducing computations utilizing a threshold to increase efficiency and speed of a video encoder is described. Computations of transform and scaling processes of a video encoder are able to be streamlined by utilizing one or more thresholds stored within one or more lookup tables. A selected threshold is compared with a value before scaling. If the value before scaling is less than the threshold, it is known that the coefficient will be zero and thus no further computations are required. Furthermore, the coefficient is set to zero. If the value before scaling is greater than the threshold, then further calculations are performed. The method is able to be extended to eliminate computations in forward transform as well. By skipping computations when the coefficient is zero, the method eliminates wasted computation power and time.

Abstract: A computer-implemented method for image adaptation includes accepting a digitally-represented input image and a target size requirement. The input image is modified by optimally determining at least one of a resolution of the input image and a quality of the input image, the quality defining an amount of information allocated to represent each pixel value of the input image, so as to produce a compressed output image meeting the target size requirement.

Abstract: An image compression method with random access capability. The method includes intracoding of digital images. The image is partitioned into small blocks and each block is coded independently of other blocks in the image. The encoder generates a fixed and predetermined number of bits for each block. The decoding of each image block is able to be done independently of any other image block.

Abstract: A method for encoding an image of a video stream divided into macroblocks comprising determining a maximum of variance of luma blocks in a macroblock, determining if the maximum of variance exceeds a predetermined threshold, determining if the motion vectors of the macroblock are in correlation with a reference macroblock, determining if the macroblock is not an edge macroblock and setting a first quantization level for the macroblock if it meets these conditions and setting a second quantization level for the macroblock if it does not meet these conditions, where the second quantization level is greater than the first quantization level.

Abstract: An image processing apparatus includes: an intermediate code generating unit that, when a data string that matches an input data string of image data is found from data string of the image data input in the past, outputs a length and a position of the found data string and, when a data string that matches with the input data string is not found, outputs the input data string as escape data; and an encoding unit that performs encoding with the length of the found data string, the position of the found data string, and the escape data. When a plurality of the escape data are successively output from the intermediate code generating unit, the encoding unit encodes the plurality of escape data collectively by adding, to the plurality of the escape data, information representing a count value obtained by counting a number of the plurality of the escape data.

Abstract: A method, system, and computer-readable storage medium for characterizing and representing images. A plurality of feature descriptors for a plurality of images are received, where each feature descriptor encodes a respective feature in an image, and where each feature descriptor is transformed into a plurality of sub-descriptors in accordance with a specified transformation scheme. The feature descriptors correspond to an image feature descriptor space for the plurality of images, and the sub-descriptors correspond to a plurality of subspaces of the image feature descriptor space, where the plurality of subspaces span the image feature descriptor space. Each subspace of the plurality of subspaces is quantized using cluster analysis applied to the sub-descriptors, thereby determining a respective one or more feature primitives for each subspace, where the feature primitives are useable to characterize image features.

Abstract: A method and apparatus, particularly suited to SIMD instruction sets, to filter streaming video information encoded under a predictive encoding algorithm specified under video encoding standards, such as MPEG 4 or H.264/AVC. The filtering operation de-blocks or removes unwanted borders in the perceived video. During the filtering process, a series of filtering mask is generated based on temporal and spatial statistics of predictive encoded video information, which is then recursively applied to the video in order to gate filtered or unfiltered video to an output channel according to coefficients of the masks. The filtering mask effectively yields a decision or rule-based map that transforms the video on a pixel-by-pixel basis thereby avoiding complex and processor-intensive decision tree logic customarily required to process individual pixels of successive macroblocks that may have different filtering requirements.

Abstract: An image processing system is adapted to compress a captured image having a plurality of regions of interest (ROIs). The image compression device includes an image dividing unit, a resolution distribution unit and an encoder. The image dividing unit divides the captured image into a number of blocks according to a predetermined size. The resolution distribution unit distributes a display resolution to each ROI of the captured image according to predetermined display information which includes a position and a resolution level of each ROI. The resolution distribution unit further obtains the blocks covered by each ROI according to the position of each ROI. The encoder separately encodes each block in the captured image according to the resolution level of each block using predetermined rules to obtain compression strings of each block, and generates compression image based on the compression strings and the predetermined display information.

Abstract: This disclosure describes deblock filtering techniques in which an in-loop deblock filter of a first codec is used as a post deblock filter of a second codec. A number of techniques are also described to facilitate input parameter adjustments and allow for the effective use of the filter with both codecs. The techniques can simplify the architecture of a device that includes multiple codecs operating according to different coding standards. Specifically, the different codecs can use the same deblocking filter regardless of whether the coding standard calls for in-loop filtering or whether post filtering is used. For example, a filter designed as an in-loop deblocking filter for a codec that complies with the ITU-T H.264 coding standard can be used as a post deblocking filter for MPEG-4 video.

Abstract: A color image residue transform and/or inverse transform method and apparatus, and a color image encoding and/or decoding method and apparatus using the same are provided. The residue transform method includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and transforming the residue by using a relation between residues of color image components. The residue inverse transform method includes: generating a residue for each component by performing residue inverse transform of the residue transformed original image; and restoring the original image by adding a predicted image to the residue of each component. Also, the color image lossless encoding method using the residue transform includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and performing encoding by transforming the residue by using the relation between residues of predetermined components.

Abstract: A scaleable macro block rate control method particularly well-suited for MPEG video. There is provided a method to easily derive a quantization parameter (QP) value using information such as bit usage, previous QP values and SAD values from the past encoded and future frames. The method utilizes quantization estimation techniques based on statistical relationships between different intensity measures, such as distortion intensity, absolute difference intensity and mean of absolute difference intensity. The method is well-suited to applications utilizing MPEG video such as MPEG-1, MPEG-2, MPEG-4, JVT/H.264 standards and so forth.

Abstract: A method of losslessly compressing and encoding signals representing image information is claimed. A lossy compressed data file and a residual compressed data file are generated. When the lossy compressed data file and the residual compressed data file are combined, a lossless data file that is substantially identical to the original data file is created.

Abstract: An image capturing apparatus for capturing an image with solid state imaging devices may include a compressing section, a memory, a decompressing section, and a signal processing section. The compressing section may compress digitalized data of an image captured with the solid state imaging devices. The memory may temporarily store the compressed image data that is compressed by the compressing section. The decompressing section may decompress the compressed image data that is read out from the memory. The signal processing section may perform an image quality correction operation on the image data decompressed by the decompressing section. The compressed image data may contain a maximum value and a minimum value of pixel data in a block, information regarding positions of the maximum value and the minimum value in the block, and quantized data.

Abstract: Embodiments of the invention compress ultrasound RF data after the receiver beamformer. An efficient compression algorithm is disclosed that incorporates the use of the Discrete Cosine Transform (DCT) and the Discrete Wavelet Packet (DWP) transform, followed by quantization of the wavelet coefficients. The algorithm first processes ultrasound scanlines from the receiver beamformer using a DCT transform. In a low-power configuration, a Hadamard transform may be used instead of the DCT. The output of the DCT processing is DCT coefficients at different frequencies. An optimized wavelet packet transform is then used for each coefficient line. The wavelet filter kernels and the wavelet packet trees can be jointly optimization using a two-step optimization algorithm.

Abstract: A computer system (810) receives a desired upper bound ?Smax for a relative quantization step ?S??S??/?S?? to be used when quantizing any color in some range of colors. Here S? and S? are adjacent colors in the set of colors to be made available for the quantized image, and ?·? is a norm in a 70%-orthonormal linear color coordinate system, the norm being the square root of the sum of squares of the tristimulus values. The computer system determines (510) suitable quantization steps for the brightness coordinate (B) and the chromatic coordinates (e,ƒ) in anon-linear color coordinate system, and quantizes (520) the brightness and chromatic coordinates accordingly.

Abstract: A decoding apparatus includes a random number generating section and a decoding section. The random number generating section generates random numbers according to distribution of original data corresponding to respective quantization indexes. The decoding section generates decoded data on a basis of the random numbers generated by the random number generating section.

Abstract: An image by using a solid-state imaging sensor, the imaging apparatus including: a compression section configured to compress image data by dividing the image data into blocks each composed of same color component pixels adjacent to each other as a unit of compression; a memory used for temporarily storing compressed image data; a decompression section configured to decompress the compressed image data read out from the memory; and a signal processing section configured to carry out an image-quality correction process on decompressed image data, wherein each of the blocks is split in advance into two quantization-subject areas, block types are distinguished from each other by the position of the inter-area boundary between the two quantization-subject areas, and the compression section has a dynamic-range computation sub-section, a block-type select sub-section, and a quantization processing sub-section are provided.

Abstract: A method and apparatus are provided for generating a halftoned image from an image compressed by a domain transformation yielding coefficients for resulting domain components and by a coding operation by which these coefficients are coded. The method includes performing a decoding operation by which decoded coefficients (yp) are obtained and performing a thresholding operation by which a bitmap is obtained, wherein only certain decoded coefficients (yp) verifying a selection criterion are selected and taken into account in the thresholding operation.

Abstract: A decoding apparatus includes a classification section, a distribution-information generation section and an inverse-quantization-value generation section. The classification section classifies quantization indices contained in input code data into a plurality of groups. The distribution-information generation section generates distribution information of the quantization indices for each group, based on the quantization indices classified by the classification section. The inverse-quantization-value generation section generates inverse quantization values, which correspond to the respective quantization indices, based on the distribution information generated by the distribution-information generation section.