Abstract: The invention provides a system and method for JPEG encoding an image that includes variable quantization for each block, depending upon the classification of each block, which is dependent on the classification of pixels in that block.

Abstract: A video-retrieval apparatus includes an input unit that receives a sample video extracted from a predetermined video; an edge-histogram-generation unit that generates an edge histogram according to the type of edges that are included in the discrete cosine transform (DCT) blocks by frames that include a plurality of sub-areas consisting of a plurality of DCT blocks; a key-frame-selection unit that selects a key frame from the sample video based on the edge histogram; and a video-retrieval unit that retrieves a video that matches the sample video by measuring the similarity rate between the selected key frame and the key frame selected from the video in storage.

Abstract: An image information coding apparatus codes an input image signal in a manner optimized on the basis of the visual characteristics. In quantization, an input image signal is divided into blocks, an orthogonal transform is performed on a block-by-block basis, and resultant orthogonal transform coefficients are quantized. A quantizer includes a weighter for, in the quantization, performing weighting on each component of the orthogonal transform coefficients by means of an addition operation on a parameter specifying one of elements of a series of numbers arranged in accordance with a predetermined rule in correspondence with quantization step sizes.

Abstract: Implementing a two-dimensional inverse discrete cosine transform function includes executing two one-dimensional inverse discrete cosine transforming functions. Each of the one-dimensional functions is controlled to operate on a matrix of coefficients in either of two different directions.

Abstract: The present invention provides a method for detecting and classifying block edges from DCT-compressed images, and more particularly, a fast method for classifying the edge direction of each block in the DCT-compressed images. The method includes: extracting DCT coefficients by blocks constituting the compressed image; and applying an arithmetic operation defined for each direction component to the DCT coefficients, and comparing the results of the arithmetic operations to determine the edge direction component. The present invention is directly applied in the DCT domain based on the quantitative analysis on the contribution factor of each DCT coefficient to formation of the directional pattern of the block edge, thereby drastically reducing the computational complexity of arithmetic operations necessary to the detection and classification of block edges.

Abstract: A motion-picture-experts group (MPEG) decoder performs AC prediction to decode first-column or first-row coefficients that are coded as differences from corresponding coefficients in a prior block or an above block. Rather than perform AC prediction between the variable-length decoder (VLD) and the inverse-quantizer (IQ), AC prediction is performed after the IQ. Post-IQ AC prediction allows the VLD and IQ to be constructed as a unified stage, improving decoding speed or efficiency as a single hardware stage can be used for the combined VLD/IQ. Rather than store prior-block quantized DCT coefficients, a coefficient store stores post-IQ DCT coefficients and quantization parameters. A Q-subtractor operates on the IQ output using the current quantization parameter, while another Q-subtractor operates on the stored coefficients and stored quantization parameter. The Q-subtractor subtracts a signed, odd-rounded quantization parameter from a coefficient.

Abstract: Coded, or compressed data of moving pictures is received through a transmission path. The picture type of the compressed data is detected from the received compressed data of moving pictures. If the picture type of the received compressed data of moving pictures is found to be intra picture, predetermined image data is supplied to a monitor so that it can be displayed on the monitor, and also to a memory so that it can be stored in the memory. If the picture type of the detected compressed data is found to be inter picture, the image data resulting from decoding the received compressed data and the image data stored in the memory are added together, and the data resulting from the addition is supplied to the monitor so that it can be displayed on the monitor and also to the memory so that it can be stored in the memory. Therefore, the image to be monitored and to be cautious about can be displayed on the monitor.

Abstract: An images combination processing system has a CCD or an imaging element including CCDs for picking up an image, compression processing portions for applying JPEG compression, etc. to image data in respective areas into which a picked-up image is divided, a buffer for storing temporarily compressed data that were processed by the compression processing portions, a compressed data combining portion for reading the compressed data being processed by respective compression processing portions from the buffer and combining them into one image file, and a storage media. Each compression processing portion has a restart marker inserting portion for inserting restart markers into the compressed data while circulating eight types of restart markers and also inserting a special restart marker into a rearmost portion of the compressed data, and a data length counter for counting a data length of the compressed data to which the restart markers are inserted.

Abstract: A decoding unit (12) decodes an image according to JPEG 2000. A simplifying unit (30) comprises an automatic transformer (32) which compares an elapsed time to a time limit at each stage of decoding the image and switches the decoding process to a simplified process if necessary. For instance, if the playback of a motion picture takes over 1/30 second, the simplified process, in which only low frequency components are decoded, is conducted by the automatic transformer (32).

Abstract: A decoding device includes a variable-length decoding circuit, a first buffer, a second buffer and a DC/AC prediction circuit is disclosed. The variable length decoding circuit decodes a first block and a second block from a compressed media stream. The first and second buffers are electrically coupled with the variable-length decoding circuit to store the first block and the second blocks, respectively. The DC/AC prediction circuit is electrically coupled with the first buffer and the second buffer. The DC/AC prediction circuit may read the first block from the first buffer when the second buffer is storing the second block.

Abstract: A video data storage and transmission system for security surveillance using a combination of data compression techniques which enable the system to operate effectively in limited bandwidth scenarios such as those found in commercial aircraft communication. High quality video is captured in the cabin or cockpit of an aircraft and stored or transmitted with sufficient update rate to enable a ground operator to confidently assess the conditions on board the aircraft in a short time. The quality of the video may be dynamically changed, and the transmission of video from air to ground initiated, at either the on-board transmitter or ground-based receiver.

Abstract: A method of encoding an input video signal for communication over a computer network, the method comprising the steps of: i) dividing each frame into a two-dimensional array of macroblocks; ii) detecting motion between each macroblock of a current frame and the corresponding macroblock of a previous frame, and coding only those macroblocks where motion is detected; iii) replacing all coefficients of non-coded macroblocks with zero coefficients; iv) applying discrete cosine transformation to coded macroblocks; v) reorganizing coefficients into a multi-resolution representation; vi) quantizing the coefficients with a uniform scalar quantizer to produce a significance map; and vii) adaptive arithmetic coding of said signal by encoding the motion information, encoding the significance map, encoding the signs of all significant coefficients, and encoding the magnitudes of significant coefficients, in bit-plane order starting with the most significant bit.

Abstract: A set of one and two-dimensional transforms is constructed subject to certain range limited constraints to provide a computationally efficient transform implementation, such as for use in image and video coding. The constraints can include that the transform has a scaled integer implementation, provides perfect or near perfect reconstruction, has a DCT-like basis, is limited to coefficient within a range for representation in n-bits (e.g., n is 16 bits), has basis functions that are close in norm, and provides sufficient headroom for overflow of the range. A set of transforms is constructed with this procedure having an implementation within a 16-bit integer range for efficient computation using integer matrix multiplication operations.

Abstract: Methods and systems for transcoding a video sequence in a discrete cosine transform (DCT) domain, wherein a transcoder receives a video bit-stream including frames and each of the frames including blocks. The video bit-stream includes an intra-frame and an inter-frame that has been encoded by motion compensation based on the intra-frame or another inter-frame. A DCT-domain motion compensation module in the transcoder re-calculates first DCT coefficients for a target block in the inter-frame. For this re-calculation of the first DCT coefficients, the motion compensation module inputs second DCT coefficients of neighboring blocks in the inter-frame, and calculates partial DCT coefficients, using significant ones of the second DCT coefficients of the neighboring blocks.

Abstract: System and method for processing time-based media such as sequences of images, audio sequences, and the like on a computing device such as a personal computer. A method may comprise receiving a plurality of sample data, processing the sample data based on a type of the sample data, and returning a plurality of processed sample data. The processing may include performing video compression of the sample data if the sample data is video, including identifying difficult to compress frames by determining a color frequency chart for each video frame and comparing the color frequency charts of neighboring video frames. The processing may also include performing either speech to text translation or speech compression when the sample data is voice, performing music compression when the sample data is music, and performing either text to speech translation or performing language translation if the sample data is text.

Abstract: A method of calculating the discrete cosine transform (DCT) of blocks of pixels of a picture includes the steps of defining first subdivision blocks called range blocks, having a fractional and scaleable size N/2i*N/2i, where i is an integer number, with respect to a maximum pre-defined size of N*N pixels of blocks of division of the picture, referred to as domain blocks, shiftable by intervals of N/2i pixels. The method also includes the step of calculating the DCT on 2i range blocks of a subdivision of a domain block of N*N pixels of the picture, in parallel.

Abstract: An inputted digital signal of a first format (DV video signal) is restored to a variable-length code by having its framing cancelled by a de-framing section 11, then decoded by a variable-length decoding (VLD) section 12, inversely quantized by an inverse quantizing (IQ) section 13, and inversely weighted by an inverse weighting (IW) section 14. Then, required resolution conversion in the orthogonal transform domain (frequency domain) is carried out on the inversely weighted video signal by a resolution converting section 16. After that, the video signal having the resolution converted is weighted by a weighting (W) section 18, then quantized by a quantizing (Q) section 19, coded by variable-length coding by a variable-length coding (VLC) section 20, and outputted as a digital signal of a second format (MPEG video signal).

Abstract: A pattern analyzing portion analyzes a pattern of a detected repeat field and determines whether or not the pattern of the repeat field is continuous. An inverse pull-down controlling portion controls a memory to read video data in such a manner that the repeat field detected by a comparator is removed from input video data in a period that the pattern of the repeat field is continuous. The inverse pull-down controlling portion controls the memory to read video data in such a manner that a repeat field detected by the comparator is not removed from the input video data in a period that the pattern of the repeat field is discontinuous. In other words, an inverse 2:3 pull-down process is controlled corresponding to the continuity of a pattern of a repeat field. In addition, it is determined whether an input original material is a progressive-scanned video material or an interlace-scanned video material corresponding to the continuity of the pattern of the repetitive material.

Abstract: An inputted digital signal of a first format (DV video signal) is restored to a variable-length code by having its framing cancelled by a de-framing section 11, then decoded by a variable-length decoding (VLD) section 12, inversely quantized by an inverse quantizing (IQ) section 13, and inversely weighted by an inverse weighting (IW) section 14. Then, required resolution conversion in the orthogonal transform domain (frequency domain) is carried out on the inversely weighted video signal by a resolution converting section 16. After that, the video signal having the resolution converted is weighted by a weighting (W) section 18, then quantized by a quantizing (Q) section 19, coded by variable-length coding by a variable-length coding (VLC) section 20, and outputted as a digital signal of a second format (MPEG video signal).

Abstract: An optimal scanning method for coding/decoding an image signal is provided. In a method of coding an image signal through a discrete cosine transform, at least one is selected among a plurality of reference blocks. A scanning order in which to scan blocks to be coded of the reference blocks is generated and the blocks to be coded are scanned in the order of the generated scanning order. The at least one selected reference block is temporally or spatially adjacent to the block to be coded. When the blocks to be coded are scanned, probabilities that non-zero coefficients occur are obtained from the at least one selected reference block, and the scanning order is determined in descending order starting from the highest probability. Here, the scanning order is generated to be a zigzag scanning order if the probabilities are identical. The optimal scanning method increases signal compression efficiency.

Abstract: Transcoding as from MPEG-2 SDTV to MPEG-4 CIF reuses motion vectors and downsamples in the frequency (DCT) domain with differing treatments of frame-DCT and field-DCT blocks, and alternatively uses de-interlacing IDCT with respect to the row dimension plus deferred column downsampling for reference frame blocks.

Abstract: A moving picture reproducing device includes a compressed data buffer, a display size obtaining unit, a resolution selecting unit, four kinds of resolution decoding units, and a frame data buffer. Compressed moving picture is received by the compressed data buffer and decoded in one of the four kinds of resolution decoding units. The display size obtaining unit obtains a display size of the decoded moving picture when the image is displayed on a display device. The resolution selecting unit selects one resolution decoding unit from the four kinds of resolution decoding units, according to the display size obtained by the display size obtaining unit. When the moving picture is reduced and displayed on the display device, it is not required to decode the moving picture in an original resolution. The moving picture reproducing device decodes the compressed moving picture in a necessary and the minimum resolution.

Abstract: A robust fine granularity scalability video encoding includes a base layer encoder and an enhancement layer encoder in which motion compensated difference images are generated by comparing an original image to predicted images at base layer and enhancement layer with motion compensation. Based on leaky and partial predictions, a high quality reference image is constructed at the enhancement layer to improve temporal prediction. In the construction of the high quality reference image, one parameter ? controls the number of bitplanes of the enhancement layer difference coefficients used and another parameter ? controls the amount of predictive leak. A spatial scalability module allows the processed pictures at the base layer and the enhancement layer to have identical or different spatial resolutions.

Abstract: A single compression engine determines a plurality of discrete cosine transform (DCT) coefficients based on a discrete cosine transform of a plurality of blocks of data. The single compression engine provides first and second DCT-encoded signals. The first DCT-encoded signal uses at most t coefficient bits to represent each of the DCT coefficients. The second DCT-encoded signal uses at most u coefficient bits, where u is less than t, to represent each of the DCT coefficients.

Abstract: A method for reducing the memory requirements for decoding a bit stream is provided. The method initiates with receiving a video bit stream. Then, a frame of the bit stream is decoded into a transform domain representation. Next, non-zero coefficients of the transform domain representation are identified. Then, a hybrid data structure is assembled. The hybrid data structure includes a fixed size array and a variable size overflow vector. Next, the non-zero coefficients of the transform domain representation are inserted into the hybrid data structure. A computer readable media, a printed circuit board and a device configured to decode video data are also provided.

Abstract: The present invention relates to a filter circuit for a set of original data (X0–X7) able to implement in series the steps of discrete transformation (DCT2), correction (ZER) of odd transformed data and inverse discrete transformation (IDCT2). The filter circuit takes advantage of the fact that the paths corresponding to the even and odd transformed data are completely separate with the exception of a first processing stage (ST1) of the discrete transformation and a last processing stage (ST8) of the inverse discrete transformation in order to connect a first half of the data issuing from the first stage to the last processing stage. The implementation of the filter circuit is thus simplified, both making the circuit less expensive and giving it a lower power consumption. For optimized implementation, the filter circuit functions in differential mode.

Abstract: Provided are a video reproduction apparatus and method capable of effectively post-processing a video signal using a motion vector, a post-processed video signal and a difference video signal. The method includes the steps of (a) variable length decoding the compressed video signal to detect quantized discrete cosine transform (DCT) coefficients and a motion vector, when the compressed video signal is input as a bit stream; (b) inversely quantizing the quantized DCT coefficients detected in (a); (c) performing an inverse DCT (IDCT) on the DCT coefficients obtained in (a) to detect a difference video signal; and (d) selectively performing post-processing on the decoded video signal, based on the motion vector detected in (a) and the characteristics of the difference video signal detected in (c).

Abstract: A frame group target bits number calculating unit (31) reads the total number of bits on frame group basis allocatable to residual frames from a storing unit (36), updates subtracting the number of generated bits used to code a preceding frame, and transmits to a next frame target bits number calculating unit (32). The next frame target bits number calculating unit (32) calculates the target number of bits to be allocated to a next frame based on the received total number of bits and the number of residual frames with considering a frame rate value, Rf. An average frame bits number calculating unit (33) calculates the average number of bits allocated to preceding frames. A calculating unit (34) multiplies the calculated average number of bits by a predetermined coefficient, compares the resulting value with above target number of bits, selects the greater number and transmits it to a quantization step calculating unit (35).

Abstract: A discrete cosine transform (DCT) level enhancement to Motion Picture Experts Group (MPEG) video encoding is described that results in a more concise bitstream than MPEG encoding without the enhancement. One degree of freedom provided by the MPEG encoding specifications is whether a frame- or field-based DCT operation will be used. In the field-based DCT operations, luminance sub-blocks are built from even or odd rows of the original image, which correspond to the top and bottom fields in field-based video. This allows the encoder to take advantage of the higher correlation between rows for the same field, especially in field-based video with a high level of motion. In one embodiment, both field- and frame-based DCT operations are performed and the results are quantized. On a macroblock-by-macroblock basis, the option that results in the fewest non-zero coefficients is selected and those coefficients are used for run-time encoding.

Abstract: Provided are a filtering method and apparatus for removing blocking artifacts and/or ringing noise. The filtering apparatus includes (a) performing one-dimensional discrete cosine transform (1D DCT) on video data on a block-by-block basis in a horizontal or vertical direction; (b) performing 1D DCT in the other direction of (a) and quantization on at least one of 1D DCT coefficients for a pixel obtained by performing 1D-DCT on the video data, the pixel being selected according to pixel position; and (c) generating filtering information based on the quantized pixel coefficient obtained from (b). According to the filtering method and apparatus, it is possible to reduce the amount of calculation when obtaining filtering information to remove the blocking artifacts and/or ringing noise.

Abstract: A drift reduction method and apparatus. Drift reduction is effected in an MPEG video transcoder by decoding dropped out pixels to form a drift reference frame. The quantization indices in the current macro-block are changed accordingly in a drift reduction process. The compensated quantized frame is then variable length coded to an MPEG bitstream.

Abstract: Adaptive DCT/IDCT apparatus based on energy and method for controlling the same. The adaptive DCT/IDCT apparatus relates to a coding unit of a MPEG4/H.263 video coder, and performs an image processing operation with a high image quality at a high speed by calculating energy values for respective blocks and a mean energy value of the whole image.

Abstract: A motion picture decoding apparatus according to the invention includes: a coefficient reducing circuit for removing orthogonal transform coefficients for high horizontal frequencies from a certain sized block of orthogonal transform coefficients obtained from an input signal, thereby reducing the number of transform coefficients to half; an inverse orthogonal transformation circuit for performing an inverse orthogonal transform operation by using the transform coefficients reduced by the coefficient reducing circuit, thereby obtaining, on a block-by-block basis, reconstructed image data or time-axis prediction error data horizontally compressed to ½; an adder for generating reconstructed image data horizontally compressed to ½, based on the time-axis prediction error data provided by the inverse orthogonal transformation circuit and on predetermined reference image data; and one or more than one reference image memories for storing reconstructed image data which is included in the reconstructed image data pr

Abstract: An apparatus and method thereof to encode a moving image include a discrete cosine transform (DCT) unit performing a DCT process on input video data, a quantizer, and a motion estimation (ME) unit calculating a motion vector and a SAD per macro block. A DCT computational complexity calculator calculates a computational complexity of the ME unit, estimates a difference between the ME computational complexity and a target ME computational complexity, and updates a target DCT computational complexity based on the estimated difference. A DCT skipping unit sets a threshold value to determine whether to skip performing the DCT process on the input video data, based on the target DCT computational complexity updated by the DCT computational complexity calculator, compares the SAD per macro block, and the quantization parameter with the threshold value, and determines whether to allow the DCT unit to perform the DCT process on the input video data.

Abstract: The present invention is directed to systems and methods for video compression. In one embodiment, a method of encoding a matrix of transform coefficients is performed. The method includes receiving a matrix of transform coefficients, creating a probabilistic model representing dependencies and correlations between coefficient locations and groups of coefficients from said matrix, and utilizing the probabilistic model to create an entropy encoding of the matrix. The probabilistic model my be, by way of example, a Markov model.

Abstract: A predictive video coder performs gradient prediction based on previous blocks of image data. For a new block of image data, the prediction determines a horizontal gradient and a vertical gradient from a block diagonally above the new block (vertically above a previous horizontally adjacent block). Based on these gradients, the encoder predicts image information based on image information of either the horizontally adjacent block or a block vertically adjacent to the new block. The encoder determines a residual that is transmitted in an output bitstream. The decoder performs the identical gradient prediction and predicts image information without need for overhead information. The decoder computes the actual information based on the predicted information and the residual from the bitstream.

Abstract: A decoding apparatus comprises a variable length decoder that decodes zero-run length and nonzero coefficient, an inverse quantizer that inverse-quantizes the nonzero coefficient, a zero-run reconstruction processor that reconstruct zero coefficients, a FIFO memory that store the zero-run length data and nonzero coefficients, an inverse discrete cosine transformer that subjects the coefficients to an inverse discrete cosine transformation, and a motion compensator that subjects the transformed result to a motion compensation.

Abstract: An initial similarity candidate calculator calculates a similarity between first and second images, which are expressed by quantized DCT coefficients, on the basis of at least first and second image feature amounts of the first and second images. A coefficient conversion processor executes a coefficient conversion process for at least one of the first and second image feature amounts. Based on an image feature amount obtained by that process, a similarity calculator calculates a similarity between the first and second images. Then, a final similarity between the first and second images is determined from the calculated similarities.

Abstract: A method of conditioning a signal being communicated between a system to be controlled and a controller may include monitoring an actual output signal and conditioning the actual output signal. The method also includes determining the difference between the actual output signal and the condition signal and causing the actual output signal to be filtered based on the relationship between the difference between the actual output signal and the conditioned signal.

Abstract: An efficient and non-iterative post processing method and system is proposed for mosquito noise reduction in DCT block-based decoded images. The post-processing is based on a simple classification that segments a picture in multiple regions such as Edge, Near Edge, Flat, Near Flat and Texture regions. The proposed technique comprises also an efficient and shape adaptive local power estimation for equivalent additive noise and provides simple noise power weighting for each above cited region. An MMSE or MMSE-like noise reduction with robust and effective shape adaptive windowing is utilized for smoothing mosquito and/or random noise for the whole image, particularly for Edge regions. Finally, the proposed technique comprises also, for chrominance components, efficient shape adaptive local noise power estimation and correction.

Abstract: A system and methodology assesses whether an error correction should be applied to detected blocks based on determined correction application criteria, and, if warranted according to the assessment, applies block-specific error corrections to detected blocks. Global error corrections, such as edge corrections, are also enabled.

Abstract: A robust fine granularity scalability video encoding includes a base layer encoder and an enhancement layer encoder in which motion compensated difference images are generated by comparing an original image to predicted images at base layer and enhancement layer with motion compensation. Based on leaky and partial predictions, a high quality reference image is constructed at the enhancement layer to improve temporal prediction. In the construction of the high quality reference image, one parameter ? controls the number of bitplanes of the enhancement layer difference coefficients used and another parameter ? controls the amount of predictive leak. A spatial scalability module allows the processed pictures at the base layer and the enhancement layer to have identical or different spatial resolutions.

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, 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 slice The parameter preferably comprises an address of the first macroblock of the slice, an address of a search area in a previous frame, the search area corresponding to a current macroblock in a current frame, and a number of macroblocks comprising the slice.

Abstract: An inverse-modified discrete cosine transform and overlap-add method, and hardware structure for MPEG Layer3 audio signal decoding. In order to have the MPEG Layer3 audio signal decoder have more competitive power in the consumer market, the present invention provides a low cost fast algorithm of the inverse-modified discrete cosine transform and overlap-add, so that the quantity of the operation needed in the decoding process can be significantly reduced to enhance the system performance. Afterwards, according to the fast algorithm, the present invention provides a hardware structure that is suitable for the inverse-modified discrete cosine transform and overlap-add in the MPEG Layer3 decoder. Since the hardware structure of the present invention makes the MPEG Layer3 decoder able to be implemented by the application specific integrated circuit (ASIC), the entire system can fulfill the low cost and high performance requirements.

Abstract: A decoder decimates MPEG or other video data by subsampling the output of an inverse discrete cosine transform (IDCT) module. The decimation process is useful for reducing the volume of data that must be processed to display images on a display device, particularly when the volume of video data received at the decoder is greater than the amount needed to take advantage of the resolution of the display device. For example, high definition television data can be decimated for display on a standard television display device or in a picture-in-picture window, thereby reducing the amount of processing resources needed at the decoder and reducing the size of the frame buffers. Subsampling the output of the IDCT module reduces the volume of data and, for relatively static or constant pans, there is not a significant compounded loss of image quality as successive frames are decoded.

Abstract: In the method for managing a variable bit rate so as to provide a streaming service and in the record medium capable of being read through a computer having a record of a program to realize the inventive method, a frame rate controlling system through a removal of a frame and a fidelity controlling system are used to change a bit rate of multimedia video data and thereby provide a multimedia streaming service based on the various bit rates according to a bandwidth change of a communication network, the fidelity controlling system being gotten by differently providing selection ranges for discrete cosine transform (DCT) coefficients in a unit of a block within a frame.

Abstract: A method, apparatus, computer medium, and other embodiments for discrete cosine transform and inverse discrete cosine transform (DCT/IDCT) of image signals are described. A DCT/IDCT module includes a plurality of different cores. One embodiment of a core includes two sets of lookup tables to provide multiplication and add operations for the DCT and IDCT functions. Another embodiment of a core include one set of lookup tables, while another embodiment of a core includes no lookup table. The DCT/IDCT module provides forward DCT and IDCT functionality without the use of additional multipliers.

Abstract: The present invention relates to an apparatus and a method for vector descriptor representation and multimedia data retrieval, which can quantize a plurality of feature values described by a vector descriptor respectively, represent the quantized feature values in the form of bit or orthogonally transform the quantized bector feature values, and rearrange the feature values represented in the form of bit from the highest bit to the lowest bit or rearrange the transformed coefficient from low frequency to high frequency to represent the vector descriptor hierarchically.

Abstract: An image search system for determining a similarity of an image whose feature are represented by either one of image features amounts, a color distribution features or a frequency distribution features, to search for a similar image, including a to-be-searched image features storage unit for referring to data of an image features amount of each image to be searched, an inquiry image features input unit for receiving input of data of an image features amount of an inquiry image, a data processing unit for converting a kind of an image features amount of an image set to be an object whose kind of image features amount is to be changed to make a kind of image features amount of each image to be searched and a kind of image features amount of the inquiry image be coincident with each other, and a similarity calculation unit for comparing the image features amount of the inquiry image and the image features amount of each image to be searched based on the converted image features amount and determining a similarit

Abstract: During Motion Picture Experts Group (MPEG) video encoding a two-dimensional discrete cosine transform (DCT) is performed on data representing an original image. The resulting coefficients are then quantized, which typically results in many zero coefficients. Because of the nature of most video data, most higher-order coefficients are typically zero and the lower-order coefficients (i.e., those grouped towards the upper left of the matrix) are more likely to be non-zero. To reduce the lengths of runs among the lower-order coefficients, the coefficients can be encoded in a zig-zag pattern. In one embodiment, the zig-zag pattern is maintained and one or more masks are generated based on the output of the quantization phase. The one or more masks are used to identify the coefficients within the matrix that are non-zero. This reduces the number of accesses to memory required to encode the non-zero coefficients and runs of zero coefficients.