Abstract: Plural sum of absolute difference devices are used to calculate distortions between specified parts of specified images in a video stream. The video can be from a video camera, or other device.

Abstract: A technique for transcoding an input compressed video bitstream to an output compressed video bitstream at a different bit rate, includes: receiving an input compressed video bitstream at a first bit rate; specifying a new target bit rate for an output compressed video bitstream; partially decoding the input bitstream to produce dequantized data; requantizing the dequantized data using a different quantization level (QP) to produce requantized data; and re-encoding the requantized data to produce the output compressed video bitstream. An appropriate initial quantization level (QP) is determined for requantizing, the bit rate of the output compressed video bitstream is monitored; and the quantization level is adjusted to make the bit rate of the output compressed video bitstream closely match the target bit rate. Invariant header data is copied directly to the output compressed video bitstream.

Abstract: An apparatus and method of intraframe encoding of digital frequency-domain data. The data comprises a plurality of slices each having a plurality of blocks. Each block has a DC component and a plurality of AC components. A first DC component value of each slice is encoded. Each subsequent DC component value of each slice is represented as the difference between it and the DC component value preceeding it. For lossless encoding, the initial DC component value of each slice and the differences are encoding using Golomb-Rice.

Abstract: A method decodes a video encoded as a compressed bitstream including frames constructed as blocks. The bitstream is variable length decoded and inverse quantized to determine motion vectors and DCT coefficients of the blocks of the bitstream. The DCT coefficients are then inverse discrete cosine transformed. A low-resolution block is generated for each reconstructed block, and the reconstructed blocks are motion compensated with the low-resolution blocks to decode the video.

Abstract: An open loop system and method of transcoding a stream of compressed video data to a required lower bit rate. The invention includes the steps of: examining motion vectors for each of a set of macroblocks in the stream; determining an importance of each of the set of macroblocks based the motion vectors; and selectively modifying DCT blocks in the set of macroblocks to reduce the bit rate, wherein the modification to each DCT block is based on the determined importance of the macroblock. High coefficient dropping or re-quantization may be utilized.

Abstract: The data transfer is repeatedly performed through a path constituted of an image holding RAM→a Huffman decoding circuit→an inverse quantization circuit→a quantization circuit→a Huffman encoding circuit until a code amount of compression image data generated by the Huffman encoding circuit becomes equal to or smaller than a maximum value determined according to an image quality, and thus a quantization threshold value and a Huffman code are determined. Every time the process is repeated, the quantization threshold value stored in a table of a first RAM and a Huffman code stored in a table of a second RAM corresponding to the quantization circuit and the Huffman encoding circuit, respectively, are newly set to a slightly higher value. As a quantization threshold value to be set in a table of a third RAM corresponding to the inverse quantization circuit, a quantization threshold value set in the first RAM at the previous quantization is used.

Abstract: An digital image input, possibly being either pre-compressed or decompressed, is enhanced; its edges are preserved while any compression artifacts, like blocking and ringing, are simultaneously reduced. The enhancement method enhances images with luminance and chrominance functions, incompletely defined or undefined, on a set of pixels so that the missing information is extrapolated while the image is simultaneously enhanced. The method consists of up to three integrated sub-processes: the image sharpening flow; the de-quantization filtering; and the means of control of the local rate of flow. The image sharpening flow is an iterative nonlinear filtering schema intertwining a local median filter and a suitably chosen linear filter. A local geometric control mechanism allows selective application and adaptation of an algorithm allowing selective removal of local artifacts.

Abstract: A method and system of reducing the computation load of an MPEG decoder by changing the encoding algorithms in a video-processing system are provided. During an encoding mode, a stream of data blocks is received and at least one motion vector and one motion compensation prediction value for each macro-block are generated. The prediction value is transformed into a set of DCT coefficients. Prior to the quantizing step, the set of DCT coefficients are modified according to predetermined criteria. To this end, the total energy level of the DCT coefficients excluding the lowest 2×2 DCT coefficients is computed, and last column and last row of the DCT coefficients is discarded alternatively until the total energy level of the DCT coefficients reaches a predetermined energy level. Therafter, the discarded column or row is assigned to a predetermined value.

Abstract: A method is described for quickly and efficiently transcoding digital video (DV) data to digital versatile disk (DVD) data. The method uses the baseline method for DV to DVD transcoding (i.e., full DV decoding, and DVD encoding), but eliminates the DCT and IDCT functions from the baseline method for I (Intraframe) coded frames; and further combines the inverse quantization (IQ) and inverse discrete cosine transformation (IDCT) functions of DV decoding, and the quantization (Q) and discrete cosine transformation (DCT) functions of DVD encoding into a single quantization function for I/P (Intraframe/Predictive) coded frames and P/P (Predictive/Predictive) coded frames.

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 discrete cosine transform (DCT) domain representation. Next, non-zero coefficients of the DCT 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 DCT 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: An MPEG encoded interlaced high definition video stream is decoded and down converted to lower resolution by an MPEG decoder with a reduced amount of reference picture memory. Received frame and field DCT coded blocks are down converted to reconstructed pixel field blocks by first converting the received frame DCT coded blocks to converted field DCT coded blocks. A vertical IDCT and a horizontal IDCT are then performed on the received field DCT coded blocks and on the converted field DCT coded blocks in order to produce residual and pixel field blocks as appropriate. The vertical IDCT is an N point vertical IDCT, and the horizontal IDCT is an M point horizontal IDCT, where N corresponds to the original block size, and where N>M. The residual and pixel field blocks are spatially filtered and down sampled vertically. IDCT, filtering, and down sampling operations are efficiently combined into single linear operators.

Abstract: An image coding system converting apparatus is arranged by employing input means 102 for sequentially reading an input bit stream, a decoder unit 103 for decoding inputted data, a data buffer 104 for saving either non-compression image data or image data being decoded in a half way, an added information buffer 105 for saving either added information related to image data or added information related to a coding system, an encoder unit 106 for encoding the image data read out from the data buffer 104 with reference to the added information read out from the added information buffer 105, and output means 107 for outputting the image data encoded by the encoder unit 106.

Abstract: Provided is a transcoder for coded video the encoding mode of that is changed according to the coded data, itself, that has been compressed by transcoding, or information prepared by decoding only a part thereof. A coded data extractor partially decodes DV coded data (a) that has been input, and sends DCT coefficients (b) to an approximate image generator and to a decoder, and outputs quantization parameters (c) to a first motion vector detector. The approximate image generator generates an approximate image according to a part of the DCT coefficients (b). A first motion vector detector roughly detects motion vector candidates (e). A second motion vector detector, using the motion vector candidates (e) as an initial position, hierarchically detects a motion vector (f).

Abstract: A method and apparatus for transcoding a digital video signal is described. A first set of bits encoded in a first encoding format are received. The first set of bits are decoded to discrete cosine transform (DCT) coefficients. The DCT coefficients are transformed into an intermediate exchange format. The transformed DCT coefficients are encoded using a second encoding format.

Abstract: A method of transmitting an image over a compressed video transport, as part of an image stream, comprising determining at least one quality for at least a part of an image based on a rate of change of said part; and transmitting said image part at said quality using said transport. Optionally, the image is static. Optionally, an improvement of the image is transmitted after a time.

Abstract: A method and system for reducing the resolution of media data. Input data at a first resolution are received from a source. The input data are compressed. The input data can be downsampled to generate compressed downsampled data at a reduced resolution. The compressed downsampled data can be used to generate a frame at the reduced resolution. When the frame is needed as a reference for another frame, the compressed downsampled data can be decoded to generate decompressed downsampled data at the reduced resolution. The decompressed downsampled data can be upsampled to generate decompressed data at a resolution corresponding to the first resolution. Thus, a larger amount of data can be processed while the data are compressed. As such, data processing operations such as transcoding can be accomplished quickly and effectively while saving computing resources.

Abstract: A method for performing a reordering operation on a matrix of input data values, the method comprising: loading the data values into a computer store by forming a plurality of data strings, each data string comprising a plurality of data sub-strings and each data sub-string representing at least one of the data values, and storing each data string in a register of the computer store in which its sub-strings are not individually addressable; and performing a series of data reordering steps operating on one or more of said data strings to reorder said data values; the reordering operation being a scan-wise reordering operation.

Abstract: A technique is provided for programmably and adaptively temporally filtering pixel values of frames of a sequence of video frames. The technique includes determining a pixel value difference between a pixel of a current frame and a corresponding pixel of a temporally previous frame; and adaptively filtering the pixel of the current frame using a selected filter coefficient. The filter coefficient is selected employing the pixel value difference. For example, multiple thresholds could be employed to differentiate between multiple filter coefficients, with the pixel value difference being employed to determine which filter coefficient is selected for the adaptive filtering. The thresholds and the filter coefficients can also be programmable. Further, the temporal filter can be integrated with a repeat field detection unit of a motion video encoder in order to conserve memory bandwidth.

Abstract: A motion vector between a current block and a reference block of a reference frame is determined by calculating the exact linear cross-correlation between the current block and the potential reference blocks of the reference picture. The current block is orthogonally transformed using DCT/DST transforms of a first type without prior zero padding of the current block to generate a current quadruple of transform coefficient blocks. The current quadruple is processed together with a reference quadruple of transform coefficient blocks generated from four of the search region blocks to generate a quadruple of processed transform coefficient blocks. The quadruple of processed transform coefficient blocks is inversely transformed using inverse DCT/DST transforms of a second type to generate a block of exact cross-correlations between the current block and the search region. The motion vector is determined from the block of exact cross-correlations.

Abstract: A pipeline video decoder and decompression system handles a plurality of separately encoded bit streams arranged as a single serial bit stream of digital bits and having separately encoded pairs of control codes and corresponding data carried in the serial bit stream. The pipeline system employs a plurality of interconnected stages to decode and decompress the single bit stream, including a start code detector. When in a search mode, the start code detector searches for a specific start code corresponding to one of multiple compression standards. The start code detector responding to the single serial bit stream generates control tokens and data tokens. A respective one of the tokens includes a plurality of data words. Each data word has an extension bit which indicates a presence of additional words therein. The data words are thereby unlimited in number.

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: 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 provides a method of and system for determining whether a local area of a compressed video stream represented by a plurality of DCT encoded blocks subject to decoding and filtering/scaling is a stationary area or an interlaced moving area. Further, given such information, the invention relates to dynamically switching between frame- or field-based operations in a smart way, thus optimizing the output picture quality. Also, a DCT-domain-filtering scheme for field-based filtering/scaling of frame-DCT data is provided herein.

Abstract: The MPEG4 is expanded to permit the use of the 4:2:2 format and the 4:4:4 format. To this end, there is provided an encoder adapted for encoding a picture in terms of a macro-block made up of a block of luminance Y and a block of chrominance Cr, Cb. The encoder includes a VOP encoding unit 3 for encoding the picture as reading of a flag (cbpc) specifying the state of encoding of the chrominance block and a flag (cbpcb, cbpcr) specifying the state of encoding of the chrominance block associated with the types of the chrominance Cb, Cr is adaptively changed responsive to a flag (chroma_type) representing the chrominance format of the picture and to the flag (cbpc) specifying the state of encoding of the chrominance block.

Abstract: Provided are a method, system and program for fractionally shifting input data subject to a first transform process without first applying an inverse transformation by using a second transform process. The second transform process applies a transformed matrix to the transformed data. At least one transformed matrix is provided in non-volatile storage, wherein each transformed matrix is generated by applying the first transform process to a fractional shift matrix operator. The input data that was transformed using the first transform process is received and the at least one transformed matrix is applied to the transformed input data to generate transformed data that represents fractionally shifted transformed output data.

Abstract: The pixel values of a current macroblock are summed, and the pixel values of a reference macroblock are summed. The initial minimum sum of absolute differences between the current and reference macroblocks is determined. When the minimum sum of absolute differences is greater than the absolute difference between the summed pixel values in the current macroblock and the reference macroblock, the sum of absolute differences between the current macroblock and the reference macroblock is calculated. When the sum of absolute differences is smaller than the minimum sum of absolute differences, the value of the sum of absolute differences is set as the minimum sum of absolute differences. If all blocks of a search area have not been searched, the pixel values of a new reference macroblock are summed. When all blocks of the search area have been searched, the block type is determined and the motion vector is output.

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: In accordance with certain aspects of the present invention, methods and apparatuses are provided according to a seamless bitstream switching scheme. The seamless switching scheme can be used with scalable video bitstreams, and can take advantage of both the high coding efficiency of non-scalable bitstreams and the flexibility of scalable bitstreams. Small bandwidth fluctuations can be accommodated by the scalability of the bitstreams, while large bandwidth fluctuations can be tolerated by switching among scalable bitstreams. The flexible and effective scheme for seamless switching among scalable bitstreams significantly improves the efficiency of scalable video coding over a broad bit rate range.

Abstract: An inverse discrete cosine transform (IDCT) apparatus is disclosed. The inverse discrete cosine transform (IDCT) apparatus can satisfy the bit accuracy of the standard recommendation and enable implementation of the ASIC by a smaller logic circuit, and simplify an interface between another sections of a video decoder. According to the present invention the image recovering performance of the video decoder installed to a digital TV receiver can be enhanced.

Abstract: Systems and methods for transcoding a video stream. An incoming video stream is spatially transcoded to reduce the bit rate of the video stream. The incoming video stream is decoded and the stream parameters are saved for use in generating the output video stream. The decoded video stream is resampled and the images are spatially reduced. Using the stream parameters of the incoming video stream, an outgoing video stream is generated. Some of the stream parameters are unchanged while others are re-computed for the outgoing video stream.

Abstract: The present invention is directed to a method for encoding video data in an embedded fashion in order to achieve fine granular scalable video. The method includes the video data being transformed into a plurality of DCT coefficients. Further, the DCT coefficients are arranged into sub-groups and the DCT coefficients are scanned according to the sub-groups. The DCT coefficients being scanned by the sub-groups enables a higher level of scalability to be achieved.

Abstract: When an nth frame of encoded data is stored in a compressed-data storage area that stores 15 frames of encoded data, a target amount of code of the nth frame is decided so as to become a value that is the result of dividing the residual capacity of an area remaining in the compressed-data storage area by the number of remaining images to be stored in this remaining area. This makes it possible to prevent the target amount of code from becoming very large or very small. Even if there is a change in a photographic scene, therefore, a drastic change in image quality from frame to frame can be prevented.

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: A video coding-decoding (CODEC) method in an error resilient mode, a computer readable medium having a computer program for the video CODEC method, and a video CODEC apparatus. The video CODEC method provides more resilience against channel error such that communications are less affected by error under conditions in which errors are a serious problem such as in a wireless communications channel. In the video CODEC method, a header data part (HDP) bit region, a motion vector data part (MVDP) bit region and a discrete cosine transform data part (DDP) bit regions are partitioned from each macro block of the video data in an error resilient mode, and then the partitioned bit regions are variable-length-coded. Then, the bit regions selected from the variable-length coded bit regions according to a predetermined priority for recovery are reversible-variable-length-coded, and markers are then inserted into the variable-length coded or reversible-variable-length-coded bit regions.

Abstract: A fine-grain scalable (FGS) encoder, decoder, and corresponding methods are disclosed which utilize conditional replacement for selecting between a base layer prediction and an enhancement layer prediction. Processes include: encoding data as a plurality of discrete cosine transform (“DCT”) coefficients for each of a base layer and an enhancement layer, a first conditional replacement (“CR”) portion in signal communication with the encoder for selecting between a base layer prediction and enhancement layer prediction for each DCT coefficient of the enhancement layer to increase coding efficiency, receiving encoded DCT data from encoder, decoding the encoded DCT data to produce reconstructed data responsive to the selected prediction, and a second CR portion in signal communication with the decoder for selecting between the base layer prediction and the enhancement layer prediction for each DCT coefficient of the enhancement layer to reduce prediction drift.

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: An encoder and decoder system for realization of complexity scalability in a layered video-coding framework. The layered video encoder comprises a base layer encoder for receiving a video signal and outputting a base layer stream; and an enhancement layer encoder that includes a plurality of discrete cosine transform (DCT) modules and a selection system for selecting one of the DCT modules. The layered video decoding system comprises a base layer decoder for receiving and decoding a base layer video stream; and an enhancement layer decoder for receiving an enhancement layer video stream and the decoded base layer stream, and generating a decoded enhanced video output, wherein the enhancement layer decoder includes: a plurality of inverse discrete cosine transform (IDCT) modules; and a selection system for selecting one of the IDCT modules.

Abstract: A picture decoding device of the present invention comprises a CPU, receiving as input encoded moving picture information, for subtracting ‘1’ from a slice start code inside slice information extracted from this information, a variable length code decoding circuit provided with a horizontal position generating circuit for subtracting ‘1’ from a macro block address (MBA) when output information formed from macro block position information (VP, HP), motion vectors, picture information etc. is output, using information output from the CPU, and a motion compensation circuit for carrying out decoding processing for the moving picture information, with origin coordinates set to (0,0), using a slice start code and macro block address after subtraction.

Abstract: In coding through adaptive quantization after transforming an image into frequency areas, such as JPEG, quantization step width control information and other information are efficiently coded. An input image is processed in a blocking circuit and a quantizer. A quantization step width is determined by multiplying a matrix of a basic quantization table by an SF value of a scaling factor calculating circuit. Quantized AC components are coded in an AC component coding circuit 51. Quantized DC components are converted into DC differences and further into group numbers and additional bits. SF values are also converted into SF value differences and further into group numbers and additional bits. The DC components and the group numbers of the SF values are converted into two-dimensional Huffman codes. The above described code elements are multiplexed and outputted.

Abstract: A data compressing circuit to compress an amount of data which is stored into an image memory is provided at the front stage of the image memory which is used for a motion compensation prediction. A data decompressing circuit to return the compression data read out from the image memory to the original data is provided at the post stage of the image memory. Since the image data is compressed when reference image data is stored into the image memory which is used for motion compensation prediction, a capacity of the image memory is reduced. In this instance, since the compression of the image data is independently performed on a unit basis of a DCT block layer, it can be matched with a DCT block and successive processes can be performed.

Abstract: The present invention relates to a method and system for extracting coding parameters from uncoded video data. Encoded video data is decoded using an MPEG decoder to produce decompressed video data. A DC computation operation is performed to recover an intra-dc-precision level from the decompressed video data, such that if the intra-dc-precision level is less than a first predetermined threshold, the decompressed video data is classified as an intra-coded picture. If the intra-dc-precision level is equal to the first predetermined threshold, a discrete cosine transform (DCT) is performed to produce a set of DCT coefficients for at least one AC frequency band in the decompressed video data. Then, an average quantizer step size is computed based on the AC data and if the average quantizer step size is greater than a second predetermined threshold, the decompressed video data being processed is classified as an intra-coded picture.

Abstract: A method and system for reducing computation complexity of an MPEG digital video decoder system by scaling down the computation of motion compensation during the decoding process are provided. The video processing system processes incoming MPEG video signals including a plurality of macroblocks with a motion vector associated therewith. A non full-pel vector is converted to a full-pel motion vector on a P frame and a B frame, or on a combination of P and B frames, by rounding an odd number vector to the nearest even number vector. Then, a motion compensated MPEG video picture is performed based on the converted full-pel motion vector. As a result, a. substantial computational overhead associated with interpolation is desirably avoided.

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 two-step motion prediction for MPEG-2 interpolation case-D will yield visual artifacts if not corrected. An improved MPEG-2 decoder includes a logic gate, multiplexer, and adder. When both the horizontal (h0) and vertical (h1) motion vector components require a half pixel interpolation (case-D), the multiplexer forwards the constant minus three to the adder, otherwise a constant zero is used. Such adder modifies the DC coefficient input to the inverse discrete cosine transformer to include a correction term for the predicted pixels calculated by a two-step predictor. A correction value of −0.375 is evenly distributed over all sixty-four resulting spatial coefficients during the inverse discrete cosine transform. This results statistically in a slightly brighter set of correction terms. Such offsets result in a slightly darker prediction that is formed by the two-step predictor. The output frames are statistically correct images.

Abstract: A source coder for video, compression Of H.261 and H.263 is disclosed, including a subtracter, a coding circuit, a predicting circuit, a picture memory with motion compensated variable delay and a filter. The subtracter subtracts an input video frame by a previous predicted frame to obtain a difference. The coding circuit transforms and quantizes the difference to output a coded bit stream. The predicting circuit predicts an error from the coded bit stream. The adder adds the previous predicted frame by the error to output a new predicted frame. The picture memory stores the new compressed frame. The filter is selectively arranged after the picture memory to serve as a loop filter in H.261 mode and arranged before the subtracter to serve as a video-in filter in H.263 mode.

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: A system and method for generating a frequency weighted (FW) matrix for use in a Fine-Granularity-Scalability (FGS) video coding system. The system comprises: a system for plotting the average discrete cosine transform (DCT) residuals versus the zigzag DCT scan line locations for a sample video frame encoded both at a predetermined base layer bit-rate and at approximately three times the predetermined base layer bit-rate; a system for generating the difference plot of DCT residuals versus the zigzag DCT scan line locations for the video frame encoded at both the predetermined base layer bit-rate and at approximately three times the predetermined base layer bit-rate; and a system for matching and normalizing a staircase curve to the average difference plot, wherein the staircase curve values can be further mapped into the weights for the FW matrix.

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: 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 said circuit less expensive and giving it a lower power consumption. For optimized implementation, the filter circuit functions in differential mode.

Abstract: The present invention provides a method of supplementing a digital picture with a shorter delay time and less calculations. The padding method is applied to a picture having a great motion, and results in producing a prediction signal with small errors. The present invention also provides an apparatus using the same method. To be more specific about the method, in a digital picture data including picture information indicating an object, a picture is resolved into a plurality of regions adjoining with each other, and each of the insignificant sample value of a region containing the boundary of the object shape is supplemented (padded) by the values obtained from transforming of the significant pixels near to the insignificant pixels.