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.

Abstract: The present invention can realize an image processing device and an image processing method that enable a simplified circuit configuration. An image encoding device (200) encodes an input image (91) in an ordinary process that is the same as main encoding on the basis of a predictive quantization parameter (QPd), while encoding the input image (91) in a simple manner (simplified process) on the basis of the predictive quantization parameter (QPd) and quantization parameters (QP) approximate to the predictive quantization parameter (QPd). The image encoding device (200) calculates a code quantity ratio R_reduction between a high-precision generated code quantity obtained through an ordinary process based on the predictive quantization parameter (QPd) and a generated code quantity obtained through a simplified process based on the predictive quantization parameter (QPd).

Abstract: Provided is a table generation method of decoding a variable-length code. The table generation method includes receiving a variable-length code table and a search width N, generating a K-ary tree from the variable-length code table and the search width N, and generating an N-bit code table from the K-ary tree.

Abstract: An apparatus and method for encoding and decoding image data. The image data encoding apparatus includes: a transformer transforming pixel values of an image in a time domain into pixel values in a frequency domain; a quantization coefficient determiner determining a quantization coefficient proportional to a number of bits per pixel of the image; a quantization unit quantizing the pixel values transformed by the transformer based on the quantization coefficient determined by the quantization coefficient determiner; and an entropy encoder generating a bitstream of the quantized pixel values.

Abstract: The invention relates to a device for double pass encoding of a video data stream comprising: a first type encoding means performing the first encoding pass, a second type encoding means performing the second encoding pass. According to the invention, the second type encoding means are different from the first type encoding means and the second type encoding means use encoding information originating from the first encoding pass. Application to MPEG-2 and H.264 encoding.

Abstract: A method (100), an apparatus, and a computer program product for automatically producing a compact representation of a colour document are disclosed. In the method, a digital image of a colour-document page is segmented (110) into connected components in one-pass, block raster order. The digital image of the page is partitioned into foreground and background images using layout analysis (120) based on compact, connected-component statistics of the whole page. At least one portion of the background image where at least one portion of the foreground image obscures the background image is inpainting (520) in one-pass block raster order. The foreground and background images are combined (130) to form a compact document. A method, an apparatus, and a computer program product for segmenting a digital image comprising a plurality of pixels are also disclosed.

Abstract: The present invention enables a circuit configuration to be simplified. An image encoding device (100) receives an input image (91) that is line-scanned in units of MBs as scan blocks, each constituted by a plurality of 4×4 blocks, while being scanned in units of 4×4 blocks as encoding blocks, each constituted by a plurality of pixels. The image encoding device (100) selects a VLC (variable length) table corresponding to a table selection index nC, which is an average value of the numbers nB and nA of nonzero coefficients as encoding values on which variable-length encoding is performed in upper-adjoining and left-adjoining 4×4 blocks of a 4×4 block as an encoding target in quantization coefficients as encoding target data based on the input image (91).

Abstract: An encoded code stream is searched for a frame generally coincident with a specific frame without having to decoding the frame to its original image. The present invention provides an image search device that searches an object encoded code stream formed by compression coding of a plurality of frames for a frame generally coincident with a specific one, which includes a decoder for making entropy decoding of the object encoded code stream to generate quantization coefficients of each frame, a matching unit for making matching between the quantization coefficients of the specific frame and those of each frame which are generated by the decoder and correspond in sample position to those of the specific frame, and a judging unit for judging, based on the result of matching, whether the frame is generally coincident with the specific one.

Abstract: A method, system and computer program product that involves receiving and initializing a digital image. Quantization is preformed on the digital image using at least two multiplication operations. Finally, a compressed version of the digital image is presented for viewing and/or storage or transport.

Abstract: According to one embodiment, a moving picture coding device which performs a motion-compensated prediction for moving picture data in macroblocks, applies discrete cosine transform and quantization to a prediction error obtained by the motion-compensation prediction to obtain a quantization coefficient, and applies variable-length-coding to the quantization coefficient together with a motion vector to be obtained by the motion-compensation prediction, when controlling each coding mode of target macroblocks for the variable-length-coding in response to a picture type, the coding device determines whether the quantization coefficient is not smaller than a threshold if the picture type is a B, performs motion detection processing only by frame prediction if the quantization coefficient is not smaller than the threshold, performs the motion detection processing after conventional frame/field prediction determination if the quantization coefficient is smaller than the threshold, and skips coding processing of the

Abstract: This invention relates to a coding method for motion-image data and others effective in a special interactive environment for transmitting motion-image data with information concentrated on only a partial region of a display image as in a two-way interactive system implementing real-time two-way interaction. The coding method involves dividing an image frame forming motion-image data into a plurality of rectangular regions, and grouping each of these rectangular regions into a preset ROI and a non-ROI. These rectangular regions are sequentially compressed so that a code length of a rectangular region grouped into the ROI is larger than a code length of a rectangular region grouped into the non-ROI, thereby generating coded data of each image frame.

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: 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: An image distribution apparatus divides image data of a single frame into a plurality of blocks, orthogonally transforms the blocks and calculates transformation coefficients, quantizes the calculated transformation coefficients, codes the quantized transformation coefficients, and distributes the coded image data. The image distribution apparatus acquires the quantized transformation coefficients, stores the acquired transformation coefficients in a storage unit, calculates differences between the transformation coefficients of a first frame and the transformation coefficients of a second frame stored in the storage unit in a unit of block, counts blocks whose difference values calculated above are equal to or greater than a predetermined value as changing blocks of the first frame, and determines that the first frame has changed when the counted number of blocks is equal to or greater than a predetermined value.

Abstract: Methods and systems for spatial data encoding and decoding are described. A tile may be designated within a source frame. The tile may be divided into at least one bit area. A particular message bit value of a message may be accessed. A statistical property calculation may be performed on a pixel variable value of available pixels within the tile. A pixel variable value of pixels in the particular bit area of a target frame may be shifted to encode a particular message bit. A particular pixel variable value of a particular pixel of the plurality of pixels may be shifted by a shift value. The shift value may be in accordance with the statistical property calculation, the particular message bit value, and a particular modulation pattern value of the plurality of modulation pattern values for the particular pixel within the particular bit area.

Abstract: Embodiments of the invention are directed toward reversible/invertible and lossless, image data hiding that can imperceptibly hide data into digital images and can reconstruct the original image without any distortion after the hidden data have been extracted in various digital image formats including, but not limited to Joint Photographic Experts Group (JPEG). In particular, embodiments of the invention provide a lossless data hiding technique for JPEG images based on histogram pairs. that embeds data into the JPEG quantized 8×8 block DCT coefficients and achieves good performance in terms of peak signal-to-noise ratio (PSNR) versus payload through manipulating histogram pairs with optimum threshold and optimum region of the JPEG DCT coefficients. Furthermore, the invented technology is expected to be able to apply to the I-frame of Motion Picture Experts Group (MPEG) video for various applications including annotation, authentication, and forensics.

Abstract: Coding quantized transform coefficients as occur in image compression combines a position identifying method to identify the relative position of clusters of consecutive non-zero-valued coefficients, an amplitude event identifying method to identify amplitude events in the clusters of non-zero-valued coefficients, and a coding method to code the position events, amplitude events, and signs of the amplitudes in the clusters. The method is particularly applicable to a series of quantized transform coefficients where clusters are likely-to-occur.

Abstract: A method of coding an original image, including: partitioning (S110) the original image into blocks; determining (S120) a coding condition for a current one of the blocks; and coding (S130) the current block according to the determined coding condition, wherein the determining (S120) of the coding condition for the current block includes calculating (S210) a first spatial-activity value indicating complexity of at least a part of regions of the current block; comparing (S220) the first spatial-activity value with a first predetermined threshold value; determining (S230), as the coding condition for the current block, a first coding condition for small partitioning size, when the first spatial-activity value is smaller than the first predetermined threshold value; and determining (S240), as the coding condition for the current block, a second coding condition for large partitioning size, when the first spatial-activity value is equal to or larger than the first predetermined threshold value.

Abstract: What is disclosed is a system and method for encoding and decoding chrominance values of a digital images. In one example embodiment, a digitized image comprising a plurality of pixels is received. A degree of chrominance precision is determined for a selected pixel based upon the luminance level associated with the selected pixel. Each of the chrominance values for the selected pixel are quantized based upon the chrominance precision. The quantized chrominance values for the selected pixel are then output. In such a manner, pixels associated with high or low luminance levels have chrominance values that are encoded with less precision than pixels associated with intermediate luminance levels. Varying the degree of precision of chrominance encoding corresponds directly to observed human-eye sensitivity where determining an exact color or hue of very bright or dark patches can be difficult relative to patches having an intermediate brightness. Various embodiments have been disclosed.

Abstract: A bit rate control circuit for image compression includes a compression unit, a R-value calculation unit, a linear quantization factor (LQF) calculation unit. The compression unit is used to performs a first quantization process on an image based on a default LQF (LQFini) to obtain an initial bits per pixel (bbpini) with an initial number of zero coefficients (Rini). The R-value calculation unit calculates out a target R value (Rtarget) based on the initial bits per pixel (bbpini), the initial number zero coefficients (Rini), and a target bpp (bbptarget). The LQF calculation unit calculates a target LQF (LQFtarget) based on the target R value Rtarget. The LQFtarget can be used to perform a second compression on the image to obtain a compressed image corresponding to the target bpp (bpptarget).

Abstract: A method for coefficient bitdepth limitation in an encoder and/or bitstream generation apparatus including the steps of (A) generating one or more residual block coefficients in response to a video signal and one or more coding parameters and (B) manipulating the one or more coding parameters such that the one or more residual block coefficients are prevented from having values greater than a bitdepth of the video signal plus a predefined number of bits.

Abstract: A data compression system and a data compression method using the same are provided. The data compression method includes acquiring original data from a memory and performs image processing and quantization on the original data to transform the original data into a quantization matrix. The data compression method then transforms the quantization matrix into a digital sequence based on a coding table and compares the data volume of the digital sequence and a target volume to generate a volume difference. The data compression method transforms the digital sequence into an inverse quantization matrix based on the volume difference and then transforms the inverse quantization matrix into a modified digital sequence based on the volume difference. The data compression method repeats the processes until the data volume of the digital sequence is substantially equal to a target volume or within an acceptable range of the target volume.

Abstract: An apparatus including a transformation circuit and a scaling/quantization circuit. The transformation circuit may be configured to generate one or more transform coefficients in response to a video stream and one or more first control signals. The transformation circuit may be further configured to limit transform coefficients for residual 4×4 blocks to a 16-bit value when the video stream comprises 8-bit video data. The scaling/quantization circuit may be configured to generate one or more quantization coefficients in response to the one or more transform coefficients and one or more second control signals.

Abstract: An image processing apparatus, a printing apparatus and an image processing method are provided which can perform quantization processing on image data at high speed based on an error diffusion method while at the same time avoiding degradations in a quality of printed images. When the error value represented by the error data is equal to or less than the reference value, at least a part of the data portion that can represent an error value in excess of the reference value is eliminated to compress the error data.

Abstract: A method and apparatus for a novel statistical model based on Benford's law for the probability distributions of the first digits of the block-DCT and quantized JPEG coefficients. A parametric logarithmic law, the generalized Benford's law, is formulated. Furthermore, some potential applications of this model in image forensics, which include the detection of JPEG compression for images in bitmap format, the estimation of JPEG compression Q-factor for JPEG compressed bitmap image, and the detection of double compressed JPEG image. Experimental results demonstrate the effectiveness of the statistical model used in embodiments of the invention.

Abstract: An image encoding method and an image decoding method, the image encoding method including: degrading a quality of a first image which is obtained through a sensor of an imaging device to generate a second image having a target resolution; generating additional information which represents a transform relationship between the first and second images; and transmitting the additional information and the second image.

Abstract: An image processing method includes a step of converting halftoned pixels of an image to be printed represented at a first lower tonal resolution into pixels represented at a second higher tonal resolution. Image processing is used on the pixels having a higher tonal resolution to reduce image quality artifacts when the pixels are printed at the first lower tonal resolution. In a preferred embodiment, the image processing includes error diffusion of a sigma delta modulation.

Abstract: Disclosed are a moving-picture compression encoding apparatus comprising a motion-compensated predicting unit that includes a first cost calculator for generating cost values based upon difference information indicative of differences between prediction signals generated by a prediction signal generator and a moving-picture signal input to the moving-picture compression encoding apparatus; a preliminary selector for preliminarily selecting a plurality of blocks based upon the cost values and outputting the blocks to a second cost calculator; the second cost calculator for generating new cost values by applying a frequency conversion to the difference information regarding the block sizes that have been output from the preliminary selector; and a block size selector for selecting an optimum block size based upon the cost values resulting from the frequency conversion.

Abstract: A conversion control unit divides a transform coefficient into code blocks. A storing device has a storage capacity corresponding to data size of the code blocks. To the conversion control unit, rotation/inversion control information including information of the rotation angle and the inverting direction is input. The conversion control unit generates a control signal on the basis of the rotation/inversion control information and sub-band information of the transform coefficient. An address generating unit generates a write address on the basis of a control signal. By accessing the storing device in predetermined order on the basis of the write address at the time of writing the code block to the storing device, an image rotating/inverting process is performed.

Abstract: An imaging device, is provided, comprising: a plurality of compression circuits configured to receive K initial imaging signals and to generate second through Kth modified imaging signals, and a plurality of delay values; and a bit multiplexer configured to generate a compressed bit stream based on a first imaging signal, second through Kth modified imaging signals, and the delay values, each compression circuit including: a delay computer configured to determine a delay value by comparing two adjacent initial imaging signals, a delay circuit configured to delay a first of the two adjacent imaging signals by the delay value to generate a delayed imaging signal; a subtractor configured to subtract the delayed signal from a second of the two adjacent imaging signals to generate a reduced imaging signal; and a quantizer configured to generate a quantized imaging signal corresponding to the second of the two adjacent imaging signals.

Abstract: According to an embodiment of the invention, there is provided an image decoder for decoding encoded image data in an image block unit, including: a storage device configured to store a DC component of a past image block coefficient as a prediction value; a predict circuit configured to predict a DC component of a current image block coefficient using the prediction value; an inversely quantizing circuit configured to inversely quantize an image block coefficient outputted from the predict circuit; and a saturation processing circuit to execute a saturation processing of an image block coefficient outputted from the inversely quantizing circuit. A DC component of the image block coefficient outputted from the inversely quantizing circuit and a DC component of the image block coefficient after execution of the saturation processing are respectively inputted to the storage device.

Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.

Abstract: A video encoding method includes selecting one combination, for each block of an input video signal, from a plurality of combinations. Each combination includes a predictive parameter and at least one reference picture number determined in advance for the reference picture. A prediction picture signal is generated in accordance with the reference picture number and predictive parameter of the selected combination. A predictive error signal is generated representing an error between the input video signal and the prediction picture signal. Encoding the predictive error signal, information of the motion vector, and index information indicating the selected combination is included.

Abstract: Provided is an apparatus, medium, and method for processing neighbor information in a video decoder that can minimize the number of memory accesses. The apparatus includes a neighbor information providing unit and a storage unit. If at least one spatially neighboring block of a current block exists in memory, the neighbor information providing unit can access information of all neighbor blocks from the memory and provides the accessed information as neighbor information. The storage unit stores the neighbor information provided by the neighbor information providing unit and outputs the stored neighbor information to the plurality of modules.

Abstract: An image coding apparatus is provided which satisfies various levels of demands on image distribution, both from image providers and from users. The image coding apparatus includes a coding block which codes predetermined image data. A separation unit separates the coded image data into basic data for reproducing contents of the coded image data as a visible image, and complementary data for complementing the basic data, so that the two pieces of data are distributed on different occasions. An adding unit adds information for independent copyright control to at least either one of the basic data and the complementary data.

Abstract: A method and apparatus for reducing motion blur in digital images. An imager captures a reference frame and a plurality of target frames. Feature blocks preferably containing strong two-dimensional features are identified in the reference frame. Corresponding features are identified in the target frames and motion vectors representing the movement of features are calculated. Based at least in part on the motion vectors, corresponding pixels in the reference and target frames are identified and combined to form an output image. Efficient methods for identifying corresponding features in apparatuses with small buffer memories by serially processing frame strips are also disclosed.

Abstract: A server device compares an image before changing with an image after changing and specifies a difference image that is an image part different between the two images. The server device determines patterns of boxes (rectangles) enclosing the difference image. In image transmission from the server device, the box becomes a macro block being a unit of image compression. The server device specifies from among the patterns of the enclosing box group, an optimal box group that is a pattern of the enclosing box group requiring the shortest response time. The server device sets each of the boxes that make up the specified optimal box group as a unit of macro block, and performs compression coding of the difference image in the set units. The server device transmits partial image information including the compression-coded difference image and the coordinates of the difference image to the client device.

Abstract: An image processing system that can reduce the amount of operations for compression processing includes a characteristic region detecting section that detects a characteristic region from an image and a compressing section that compresses the image by compressing each prescribed partial region. The compressing section compresses an image of a partial region included in a characteristic region by using pixel values of pixels, the number of which is larger than the number of pixels used for compressing an image of a partial region included in a region other than the characteristic region.

Abstract: A method for context-modeling coding information of a video signal for compressing or decompressing the coding information is provided. An initial value of a function for probability coding of coding information of a video signal of an enhanced layer is determined based on coding information of a video signal of a base layer.

Abstract: A method for sending compressed data representing at least part of a digital image includes the following steps: encoding (220) source data representing said part to obtain first compressed data having a given size; based at least on said size, including (210) said first compressed data either in a first slice comprising second compressed data representing other parts of the digital image or in an empty second slice; sending the slice comprising said first compressed data. A corresponding device is also described.

Abstract: A method of compressing a digital image defined by a plurality of pixel values in each of one or more channels includes adjusting each pixel value in each of the one or more channels by an average pixel value for that channel. The method further includes splitting each adjusted channel into one or more image blocks, and converting each image block into a frequency block that is a frequency-domain representation of that image block.

Abstract: An apparatus for 3D mesh compression based on quantization, includes a data analyzing unit (510) for decomposing data of an input 3D mesh model into vertices information (511) property information (512) representing property of the 3D mesh model, and connectivity information (515) between vertices constituting the 3D mesh model: and a mesh model quantizing unit (520) for producing quantized vertices and property information of the 3D mesh model by using the vertices, property and connectivity information (511, 512, 513). Further, the apparatus for 3D mesh compression based on quantization includes a decision bit encoding unit (535) for calculating a decision bit by using the quantized connectivity information and then encoding the quantized vertex information, property information and connectivity information (511, 512, 513) by using the decision bit.

Abstract: The versatile method of spatial and SNR scalable picture compression comprises: high resolution encoding (202a) an input picture (vi) yielding high resolution encoded data (coHR,LQ), being the base data; deriving a first down-scaled representative picture (p1) on the basis of the high resolution encoded data (coHR,LQ); deriving a second down-scaled representative picture (p2) on the basis of the input picture (vi); and lower resolution encoding (214) lower resolution quality enhancement data (coMR,MQ), usable for improving the visual quality of a picture reconstructable from the high resolution encoded data (coHR,LQ), on the basis of comparing the first down-scaled representative picture (p1) with the second down-scaled representative picture. This enables good bit-rate distribution for multi-resolution, multi-quality users.

Abstract: An image forming apparatus and method capable of decompressing and compressing image data. More specifically, the apparatus and method include decompressing first compressed image data, processing the decompressed image data, selecting from among a plurality of quantization tables a quantization table providing a compression ratio lower than a compression ratio of the first compressed image data, and compressing the processed image data.

Abstract: An image processing apparatus for processing multilevel image data including values of respective color components includes an adding unit configured to add quantization errors to the respective values of the color components of a target pixel, an output determination unit configured to perform quantization to determine output values of the respective color components of the target pixel based on a combination of the values of the respective color components to which the quantization errors are added, and an error calculation unit configured to calculate quantization errors of the respective color components of the target pixel based on the output values of the respective color components and the values of the respective color components to which the quantization errors are added.

Abstract: An image processing apparatus, a printing apparatus and an image processing method are provided which can perform quantization processing on image data at high speed based on an error diffusion method while at the same time avoiding degradations in a quality of printed images. When an error value represented by error data is a particular value, the error data is converted into compressed error data with a data volume less than that of the original error data.

Abstract: A system and method for effectively performing an adaptive encoding procedure includes a texture analyzer that initially determines texture characteristics for blocks of input image data. An image transformer converts the blocks of image data into sets of coefficients that represent the various blocks. A block categorizer utilizes the texture characteristics to associate texture categories with the sets of coefficients from the various blocks. Deadzone tables are provided for storing deadzone values that define deadzone regions for performing appropriate quantization procedures. A quantizer may then access the deadzone values from the deadzone tables to adaptively convert the coefficients into quantized coefficients according to their corresponding texture characteristics.

Abstract: A video encoding apparatus includes selecting one combination, for each block of an input video signal, from a plurality of combinations. Each combination includes a predictive parameter and at least one reference picture number determined in advance for the reference picture. A prediction picture signal is generated in accordance with the reference picture number and predictive parameter of the selected combination. A predictive error signal is generated representing an error between the input video signal and the prediction picture signal. Encoding the predictive error signal, information of the motion vector, and index information indicating the selected combination is included.

Abstract: A video encoding method includes selecting one combination, for each block of an input video signal, from a plurality of combinations. Each combination includes a predictive parameter and at least one reference picture number determined in advance for the reference picture. A prediction picture signal is generated in accordance with the reference picture number and predictive parameter of the selected combination. A predictive error signal is generated representing an error between the input video signal and the prediction picture signal. Encoding the predictive error signal, information of the motion vector, and index information indicating the selected combination is included.

Abstract: A video encoding apparatus includes selecting one combination, for each block of an input video signal, from a plurality of combinations. Each combination includes a predictive parameter and at least one reference picture number determined in advance for the reference picture. A prediction picture signal is generated in accordance with the reference picture number and predictive parameter of the selected combination. A predictive error signal is generated representing an error between the input video signal and the prediction picture signal. Encoding the predictive error signal, information of the motion vector, and index information indicating the selected combination is included.