Abstract: A frame in a video sequence is compressed by generating a compressed estimate of the frame; adjusting the estimate by a factor &agr;, where 0<&agr;<1; and computing a residual error between the frame and the adjusted estimate. The residual error may be coded in a robust and scalable manner.

Abstract: A transmission method for video image data using an embedded bit stream in a hierarchical table-lookup vector quantizer comprises the steps encoding an image using hierarchical vector quantization and an embedding process to obtain an embedded bit stream for lossless transmission. The bit stream is selectively truncated and decoded to obtain a reconstructed image.

Abstract: Transform coefficients of sample blocks of a macroblock of a video picture are encoded by adaptively encoding in combination, the number of non-zero coefficients before the trailing one coefficients and the number of trailing one coefficients. The transform coefficients may be further encoded by adaptively encoding one or more of the signs of the trailing one coefficients, the level measures of the non-zero coefficients, the total number of zero coefficients interposed in the non-zero coefficients, and the respective run lengths of the zero coefficients. Adaptive encoding of the number and trailing one coefficients may be performed in view of one or more neighboring sample blocks, whereas adaptive encoding of level measures may be performed in view of quantization parameters of a macroblock and previously encoded level measures. Decoding may be performed in an inverse manner.

Abstract: A color solid-state image-pickup camera system is provided with a color solid-state image-pickup unit for acquiring image information by picking up an image of a subject, a vector quantization section, a first code-book storage section that stores code-book vectors for compressing image information, a vector decoding section and a second storage section that stores a plurality of kinds of code-book vectors for decompressing the image information. The vector quantization section outputs information for identifying code-book vectors that correspond to the respective blocks of the image information that has been acquired to the vector decoding section. Based upon the information, the vector decoding section selects code-book vectors that represent the luminance signal and color-difference signals, and reconstructs the respective blocks.

Abstract: A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, the method comprises the steps of: receiving the digital image as blocks of pixels; analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; compressing the block of saturated text and/or line art, if any, according to a first predetermined compression method; compressing the pictorial imagery, if any, according to a second predetermined compression method; compressing the other types of imagery, if any, according to other predetermined compression methods; and providing means of conveying the image categories to a decoder.

Abstract: An image distribution system has a source that encodes digital images and transmits them over an error-prone channel to a destination. The source has an image coder that processes the digital images using vector transformation followed by vector quantization. This produces groups of vectors and quantized values that are representative of the images. The image coder orders the vectors in the codebooks and assigns vector indexes to the vectors such that a bit error occurring at a less significant bit in a vector index results in less distortion than a bit error occurring at a more significant bit. Depending upon the format and the capabilities of the source and destination, the image coder may allocate different numbers of bits to different groups of vectors according to a bit allocation map for this allocation process. The source also has a UEP (Unequal Error Protection) coder that layers the vector indexes according to their significance.

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

Abstract: A method of compressing an image frame composed of an array of pixels in the form of digital signals comprises a two stage codebook search. In the first stage the pixelated image frame and the pixelated codebook patches are transformed to frequency domain coefficients and a pattern comparison is made between the coefficients of the image patch and the codebook patches to identify a short list of possible match codebook patches by discarding incorrectly matching patterns. In the second stage the image frame is compared with the short list of codebook patches by any desired method, e.g. by pixel comparisons, to select the best matching codebook patch.

Abstract: The block reducing unit 201 reads one block out of each block group. The pixel reducing unit 202 reads pixels on one-out-of-four basis. The block reading unit 203 sequentially reads out images. The orthogonal transformation unit 205 performs orthogonal transformation. The quantization unit 206 performs a quatization. The encode amount predicting unit 207 calculates predicted encode amounts. The quantization width calculating unit 208 determines an optimum quantization width. The quantization table generating unit 209 generates an optimum quantization table. The block-assignment encode amount setting unit 210 calculates an encode amount to be assigned to each block.

Abstract: A method of determining a quantization parameter for video compression. A block characteristic for blocks in a video frame is quantized and then used to obtain a candidate quantization parameter. With the candidate quantization parameter, a number of bits for the blocks in the video frame is summed, producing a candidate bit rate. If the candidate bit rate is greater than a predetermined bit rate threshold, the candidate quantization parameter is set as the quantization parameter.

Abstract: In video compression processing, such as MPEG-2 compression processing, the quantization (Q) matrix used to quantize discrete cosine transform (DCT) coefficients is updated from frame to frame based on a parameterized Q matrix adaptation algorithm. According to the algorithm, the Q matrix for the current frame is generated based on DCT coefficient data from the previously encoded frame of the same type (e.g., I, P, or B) as the current frame. In particular, the Q matrix is generated using a function based on shape parameters (e.g., the slope of the diagonal of the Q matrix and/or the convexity of the diagonal of the Q matrix), where the diagonal slope for the Q matrix of the current frame is generated based on the diagonal slope of a DCT map for the previously encoded frame. Before using the generated Q matrix to quantize the DCT coefficients for the current frame, the Q matrix is preferably adjusted for changes in the target mean from the previously encoded frame to the current frame.

Abstract: The present invention relates to a method of viewing and processing hyper-spectral image data compressed using a VQ algorithm. According to the invention the data is compressed using a codebook of codevectors including binary spectral vectors, which allows processing of the compressed data and viewing of data within a datacube without expanding the compressed data into the complete datacube. In order to view an image derived from a datacube, for each pixel within the image a location within the datacube is selected, an index value from the index map at that location is retrieved, and a spectral value from a spectral vector within the codebook is retrieved for said pixel, the spectral vector identified by the retrieved index. A single spectral vector is easily viewed by displaying a spectral vector from the codebook.

Abstract: A hyperspectral image encoder (10) for compressing hyperspectral imagery includes a differential pulse code modulation (DPCM) loop (26) to perform data decorrelation in the spectral domain and a discrete wavelet transform (DWT) processing means (28) to perform decorrelation in the spatial domain. The DPCM loop (26) determines an error image between a present image at the input of the encoder (10) and a predicted image. The DWT processing means (28) then divides the error image into a plurality of frequency subbands and quantizes information within the subbands in accordance with a plurality of predetermined quantization states to provide a coded output signal. In one embodiment, an interband predictor (24) is provided to predict an image, for use in calculating the error image, using the coded output signal.

Abstract: The invention concerns a method comprising a step which consists in a quantizing step relative to a pixel or group of pixels in accordance with a desired rate. The invention is characterized in that it comprises an additional step which consists in modifying the quantizing step on the basis of an information of a subjective nature concerning said pixel or group of pixels. The invention is applicable to compression of video images.

Abstract: In a pixel decoding method and apparatus, pixel dephasing caused for the field DCT mode and the frame DCT mode is to be eliminated to curtail the processing volume without detracting from the properties inherent in a picture produced on interlaced scanning. To this end, if the DCT mode is the field mode, a decimating DCT device for field mode 14 performs 4×4 decimating IDCT. If the DCT mode is the frame mode, the decimating DCT device for frame mode 15 performs IDCT on the totality of coefficients of the DCT block, separates the coefficients into two pixel blocks associated with the interlaced scanning and performs DCT separately for the separated two pixel blocks. The low frequency components of these two pixel blocks are IDCT and the two pixel are synthesized.

Abstract: In a system where two types of data are to be compressed using hierarchical vector quantization (HVQ), it would be typical for there to be two compression tables, one optimized for each type of data. A boundary between the two types may occur within a block to be compressed. In this case, a third table, optimized for a block having both types of data, is used.

Abstract: Data is transmitted using multiple description vector quantization by first quantizing the source vector at a lattice vector quantizer. After quantization, a labeling function is applied to the quantized source vector, creating a plurality of data streams. Each data stream is encoded and transmitted over a separate channel. Furthermore, the encoded data is decoded by first retrieving a representation of a sublattice point from a set of sublattice points from the data stream and then, determining a single data code word being associated with the retrieved representation of the sublattice point.

Abstract: There is disclosed an apparatus for controlling the transmission of enhancement layer video data for use in a video encoder containing a base layer encoder and an enhancement layer encoder. The base layer encoder receives input video frames and generates compressed base layer video frames suitable for transmission at a base layer bit rate to a streaming video receiver. The enhancement layer encoder compares the input video frames and a processed version of the compressed base layer video frames and generates enhancement layer video data suitable for transmission at a modifiable enhancement layer bit rate to the streaming video receiver. The apparatus comprises a base layer parameter monitor for receiving at least one base layer parameter and, in response thereto, modifying an allocation of the enhancement layer video data among corresponding ones of the compressed base layer video frames.

Abstract: Methods for coding the current frame of a video data bit stream are provided. Methods include, for example, creating and maintaining a global codebook of historic values for the macroblocks of previous frames; searching entries in the global codebook to find the best estimation of the current frame and calculate a measure of the difference between values for the two macroblocks; comparing the effectiveness of the estimation macroblock provided by the global codebook entry to the estimation provided by a motion compensation scheme; choosing the best estimation method and coding the current frame; and updating the global codebook based on the new coded macroblock.

Abstract: Using hierarchical vector quantization (HVQ) to accomplish rotation in addition to compression and decompression. During the compression step the image is divided into segments and each segment is reduced to a codeword. These codewords are transposed so that the segments will be in rotated order when printed. Then the codewords are decompressed to form segments in which the pixels are in rotated order.

Abstract: An apparatus for image coding using tree-structured vector quantization based on a wavelet transform and a method therefor are provided. The apparatus for image coding using a tree-structured vector quantization based on wavelet transform has a wavelet transform unit, a vector construct unit, an error vector unit, a scan unit, a first quantization unit and a second quantization unit. The wavelet transform unit wavelet transforms an input image signal. The vector construct unit constructs vectors, each having a tree structure in a different direction, using the wavelet transformed result. The error vector generation unit generates a plurality of error vectors by setting one of the vectors as a basic vector and performing a calculation on each of the vectors remaining with respect to the basic vector. The scan unit scans the coefficients of each of the basic vector and error vectors in a different direction.

Abstract: After decoding of an MPLFG bitstream to the form of a video signal, an information stream signal in the form of all or part of the MPEG bitstream, is transmitted alongside the video signal, embedded in the least significant bit. Recording may simply involve extraction of the embedded MPEG bitstream or, if only part of the bitstream has been embedded, an essentially “dumb” coding operation guided by the information stream signal.

Abstract: In a system where two types of data are to be compressed using hierarchical vector quantization (HVQ), it would be typical for there to be two compression tables, one optimized for each type of data. A boundary between the two types may occur within a block to be compressed. In this case, a third table, optimized for a block having both types of data, is used.

Abstract: A method of lattice-quantizing an eight-long data point to minimize storage requirements by acquiring the data point, multiplying each coordinate of the data point by {square root over (2)} to form an inflated data point, rounding each coordinate of the rounded and inflated data point to the nearest integer, modulo-two reducing each coordinate of the rounded and inflated data point to form an initial codeword, multiplying a parity-check matrix of an eight-bit Extended Hamming Code by the result of the last step to form a syndrome, correcting any single-bit errors and double-bit errors, if any, in the initial codeword and the rounded and inflated data point, transforming the coordinate system of the initial codeword to an extended quadratic residue form, creating a signal packet, and transmitting the signal packet to a receiver.

Abstract: A system and method for adaptively controlling the encoded data rate in a data compression system. The system and method sets up alternative encoded bit streams for each segment of data and selects the alternative that would produce the bit rate closest to a predetermined target bit rate for transmission. Each segment of video input is quantized based on a set quantization settings to produce a plurality of quantized segments. Each quantized segment is then variable rate encoded to produce an alternative encoded bit stream. The data rate that would be required to transmit each alternative encoded bit stream is determined and compared with a predetermined target bit rate, which is set according to the transmission rate buffer status. The selected encoded bit stream is provided to the transmission rate buffer in preparation for transmission. Having processed one segment of data, the system and method then updates its parameters for processing the next segment of data.

Abstract: In a vector quantization of a digitized image, image regions (QB) to be quantized are selected smaller than, for example, image blocks (BB) of an image (B). In the reconstruction, image points (NBP) that are not located in an image region (QB) to be quantized are interpolated and/or extrapolated.

Abstract: A transmission method for video image data using an embedded bit stream in a hierarchical table-lookup vector quantizer comprises the steps encoding an image using hierarchical vector quantization and an embedding process to obtain an embedded bit stream for lossless transmission. The bit stream is selectively truncated and decoded to obtain a reconstructed image.

Abstract: The memory requirement of MPEG decoders and SQTV/IQTV systems may be reduced by recompressing the MPEG decoded data stream before storing pixels in an external RAM. An efficient compression method for recompressing video picture data based on the tree-search vector quantization (TSVQ) is made more effective by optimizing the way the quantizer is chosen for quantizing the differences among adjacent pel vectors. This method is based on premultiplying a read-only table using quantized complexity measures relative to the centroids of the tree-like scheme used in the TSVQ processing. A plurality of precalculated tables of quantization of the prediction error of a physical parameter of blocks of digital data are produced. For each one of the regions in which a block is divided, the calculated and quantized complexity measure provides an address that selects the most appropriate precalculated table for quantizing the prediction error.

Abstract: An integrated circuit for processing a speech signal in accordance with a CELP standard includes a plurality of processing elements coupled to a data bus in parallel. Each processing element includes a multiplier and an accumulator. The integrated circuit further includes an auxiliary processing element, which is also coupled to the data bus and has a division unit and a comparator. The plurality of processing elements and the auxiliary processing element are also coupled in a pipeline formation.

Abstract: A method and an apparatus for predictively coding shape information of a video signal. An error between the current shape information and the previous shape information is obtained through the comparison therebetween. If the obtained error is greater than or equal to a predetermined reference value, the current shape information is coded. However, in the case where the obtained error is smaller than the predetermined reference value, the current shape information is reconstructed using the previous shape information. Therefore, a time-axis redundancy of the shape information is removed to prevent the transmission of unnecessary information, resulting in an increase in compression coding efficiency.

Abstract: A decoder is used in an end-to-end scalable video delivery system operable over heterogeneous networks. The decoder may software-based and computationally low complexity, or may be implemented inexpensively in ROM hardware. The system utilizes a scalable video compression algorithm based on a Laplacian pyramid decomposition to generate an embedded information stream. At the receiving end, the decoder extracts from the embedded stream different streams at different spatial and temporal resolutions. Decoding a 160×120 pixel image involves only decompressing a base layer 160×120 pixel image. Decoding a 320×240 pixel image involves decompressing and up-sampling (e.g., interpolating) the base layer to yield a 320×240 pixel image to which is added error data in a first enhancement layer following its decompression.

Abstract: A method and apparatus for selecting a quantization table containing quantization coefficients for encoding image data. A set of quantization tables is examined to determine a quantization table which meets a predetermined selection criteria. If such a quantization table is not the first table examined, other tables in the vicinity of a neighborhood of tables are examined utilizing linear searching techniques. If a quantization table which meets the selection criteria is not determined in the vicinity of the neighborhood of tables, quantization tables outside the vicinity of the neighborhood of tables are examined utilizing binary searching techniques.

Abstract: Pixel blocks of an input image are type classified based on an analysis of pixel values for each respective pixel block. A discrete cosine transform (DCT) is performed on the pixel values of each pixel block, and a quantization modification process thresholds and/or quantizes the resulting DCT coefficients based on the type classification of the respective pixel block. Once the coefficients are modified in this way and encoded, the resulting data can be decoded and dequantized in compliance with the standard JPEG sequential mode data syntax in order to construct a perceptually faithful representation of the image, without passing any additional information to the decoder concerning the quantization modification.

Abstract: A semiconductor chip integrating various functional blocks of a video codec for use in a system for real time record and playback of motion video through a computer interface such as a PC-compatible parallel port is disclosed. An innovative combination of the hardware implementing data compression and decompression based on a vector quantization algorithm with video input/output port and computer interface integrated on a single semiconductor chip provides for a cost-effective solution to processing of continuous-steam video and audio data in real time.

Abstract: A video compression system comprises a control computer 52; a plurality of encoders 54, 56, 58; a plurality of encoder buffers 60, 62, 64; a multiplexor 66; a data channel 70; a demultiplexor 80; a decoder buffer 82; a decoder 84; and display 86. The control computer controls the encoders and the multiplexor 66 to avoid overflows and underflows of data provided to the decoder buffer 82.