Abstract: A system for coding video data comprised of one or more frames codes a portion of the video data using a frame-prediction coding technique, and generates residual images based on the video data and the coded video data. The system then codes the residual images using a fine-granular scalability coding technique, and outputs the coded video data and at least one of the coded residual images to a receiver.

Abstract: To obtain real-time responses with interactive multimedia servers, the server provides at least two different audio/visual data streams. A first data stream has fewer bits per frame and provides a video image much more quickly than a second data stream with a higher number of bits and hence higher quality video image. The first data stream becomes available to a client much faster and may be more quickly displayed on demand while the second data stream is sent to improve the quality as soon as the playback buffer can handle it. In one embodiment, an entire video signal is layered, with a base layer providing the first signal and further enhancement layers comprising the second. The base layer may be actual image frames or just the audio portion of a video stream. The first and second streams are gradually combined in a manner such that the playback buffer does not overflow or underflow.

Abstract: A method and an apparatus improving the coding efficiency by representing encoded data in a compact form by means of a pattern matching technique. A waveform vector similar to a partial signal waveform of an image signal in a predetermined group of waveform vectors is searched for. When a compression encoding is performed for information to identify the waveform vector searched for, similarity information, and a position in an image signal of the partial signal waveform in accordance with a predetermined encoding rule, the position in the image signal of the partial signal waveform is encoded through replacement with position information in a predetermined partial domain of the image signal. As a result, since the position in the image of the partial signal waveform that is the most similar to the waveform vector is encoded through replacement with the position information in the predetermined partial domain of the image signal, it is possible to represent the position more compactly.

Abstract: The invention provides a video object segmentation process for parting video objects from a video or image based on Motion Picture Experts Group (MPEG) compression standard. The process uses MPEG-7 descriptors and watershed segmentation. A database stores MPEG-7 descriptors of video objects for comparison of image regions obtained from watershed segmentation and region combination. The region that is most similar to the descriptors of data in the database is the video object to be found.

Abstract: A method for variable bit rate encoding is composed of a step of obtaining first encoded data by encoding a video signal in a predetermined bit rate, a step of recording the first encoded data, a step of observing encoded information of the recorded first encoded data, a step of decoding the recorded first encoded data at a predetermined time interval, a step of obtaining second encoded data by encoding the decoded first encoded data in variable bit rate at the predetermined time interval on the basis of either one of a combination of the encoded information and an average variable bit rate to be targeted and another combination of the encoded information and information related to a target code rate, and a step of recording the second encoded data encoded in the variable bit rate. The method for variable bit rate encoding records the first and second encoded data in a recording medium while buffering the first and second encoded data respectively in the steps of recording the first and second encoded data.

Abstract: A multi-dimensionally layered encoding and decoding system having reduced the bandwidth requirements for a channel that carries an image stream encoded by the system. A source image stream is partitioned multi-dimensionally into a lower resolution layer and higher resolution layer image stream. The lower resolution image stream is encoded and decoded in accordance with certain accepted standards such as MPEG-2, MPEG-4 and JPEG. In the encoding of the lower layer image stream, a number of indicator signals are derived that indicate where a compression loss and resolution loss occurs. Additionally, the lower layer image stream is non-linearly processed to create an improved image stream and non-linear indicator for use in the upper-layer encoder. The upper-layer encoder uses the non-linear processed image stream and a decoded, reconstructed upper-layer encoded stream to derive the motion vectors and prediction frames in a motion compensation process.

Abstract: Systems and methods are provided for for encoding units of digital information such as pictures, whereby all the data is first analyzed by running a compression pass over all the data, using the in the encoder embedded rate control mechanism. Picture attributes, such as quantization scale setting and bits produced will be extracted from the resulting bitstream, and analyzing this, indiviudal unit (picture) quantization scale and bit allocation settings are prepared for a next pass for either a constant- or variable bit rate, whereby buffer boundaries are observed. In a second compression pass through the same data, a constant- or variable bit rate compressed bitstream is produced, but this time bypassing the embedded rate control mechanism, and using the prepared picture bit allocation and quantization scale settings instead. Additionally, a mechanism will supervise the total bit production accuracy.

Abstract: A video encoding scheme employs progressive fine-granularity layered coding to encode video data frames into multiple layers, including a base layer of comparatively low quality video and multiple enhancement layers of increasingly higher quality video. Some of the enhancement layers in a current frame are predicted from at least one lower quality layer in a reference frame, whereby the lower quality layer is not necessarily the base layer.

Abstract: A method and apparatus for minimizing prediction drift at low bitrates in a fine granular scalable video coding scheme that utilizes motion compensation in an enhancement layer. The method and apparatus measures motion activity within at least a portion a video; determines whether the measured motion activity is below a predetermined threshold value; codes the portion of the video with the fine granular scalable video coding scheme that utilizes motion compensation in the enhancement layer if the measured motion activity is below the predetermined threshold value; and codes the portion of the video with a fine granular scalable video coding that does not utilize motion compensation in the enhancement layer if the measured motion activity is above the predetermined threshold value.

Abstract: In an image processing apparatus and method, a plurality of objects are separated from input moving image data. The separated first object is encoded by a first encoding method. The separated second object is encoded by a second encoding method. The encoding process for the second object is controlled in accordance with encoded data of the first object.

Abstract: An image data coding apparatus includes: a memory interface which controls reading/writing of data from/to an external memory; an MPEG2 processing unit for performing a compression-coding process using a first compression ratio; and a coder/decoder which is provided between the MPEG2 processing unit and the memory interface, which performs a compression-coding process using a second compression ratio lower than the first compression ratio on data outputted from an image data coding unit to the external memory, and which performs a decoding process on data outputted from the external memory to the image data coding unit.

Abstract: It is an object to encode an image signal or a shape signal more efficiently than the prior art. As a means to accomplish the object, the change pixel detector 2 receives the input signal 1 as an input signal and detects the pixel which changes the two-valued pixel value. Further, the change pixel predictor 4 also reads out the reference image stored in the memory 3, and predicts the change pixel of the particular input signal. The difference value calculator 5 subtracts the output of the change pixel predictor 4 from the output of the change pixel detector 2. The difference value rounder 7 compares the tolerance value e and the prediction error D, and outputs x which requires the minimum bit number for being encoded in the value D−e≦x≦D+e. The output of the difference value rounder 7 is encoded by the decoder 8 to become the encoded signal 9.

Abstract: A group of video plane (GOV) layers in which the encoding start time is absolute time with an accuracy of one second is provided as a coded bit stream. A GOV layer can be inserted not only at the head of the coded bit stream but at an arbitrary position in the coded bit stream. The display time of each video object plane (VOP) included in the GOV layer is represented by modulo_time_base which represents absolute time in one second units with the encoding start time set as the standard, and VOP_time_increment, which represents in millisecond units, the time that has elapsed since the time point represented by the modulo_time_base.

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: A scalability type selection method and structure for hybrid SNR-temporal scalability that employs a decision mechanism capable of selecting between SNR and temporal scalability based upon desired criteria is disclosed. This method and structure utilizes models of the desired criteria such as the extent of motion between two encoded frames, the temporal distance between two encoded frames, the gain in visual quality achieved by using SNR scalability over temporal scalability, and the bandwidth available to the scaleable layer in deciding which form of scalability to use. Furthermore, the method and structure allows for control over the extent to which a certain type of scalability is used. By the selection of parameters used in the models, a certain type of scalability can be emphasized while another type of scalability can be given less preference. This invention not only allows the type of scalability to be selected but also to the degree to which the scalability will be used.

Abstract: The invention relates to a method and system for modulating an MPEG-4 FGS compressed video stream for variable-bandwidth transmission. A source of a video stream is provided, and a display having means for generating a control input signal for controlling one or more of video compression, error correction code generation, or symbol constellation mapping. The source video stream is compressed using MPEG-4 FGS compression to generate a compressed output video stream. The video compression is optionally performed based upon the control input signal from the display. Error correction code for the compressed video stream may be added, and its generation and addition may be optionally controlled based upon the control input signal from the display. The resulting video symbols may then be mapped to constellations, with this mapping also optionally controlled based upon the control input signal. The resulting compressed output video stream is then transmitted to the display.

Abstract: A picture signal processing system is disclosed, that comprises a decoder for generating the number of encoded bits and/or an average quantizing scale as representative value(s) of encoding parameters of an input encoded picture signal, decoding the input encoded picture signal, generating the decoded picture signal, and outputting the encoding parameters along with the generated decoded picture signal, and an encoder for encoding the decoded picture signal with the encoding parameters.

Abstract: The invention relates to a video coding method based on an adaptive frame/field encoding mode. In order to avoid an impairment of the image quality and of the compression efficiency when a video sequence comprises a lot of motion or on the contrary quasi-motionless images, an improved real time double pass encoding scheme is proposed: during the first pass, no video stream is generated, but statistical results are computed and then provided to the second pass in order to optimize during said second pass the bit rate allocation and the buffer management. This improved double pass encoding method leads to an increase of the compression efficiency of about 10%.

Abstract: An apparatus for pattern matching encoding includes a pattern extracting unit for extracting patterns in input binary or multi-level image data, an accumulating/match-checking unit for accumulating each extracted pattern and executing a match-check thereof with patterns that have been accumulated, a line segment checking unit for checking each pixel in the match pattern or the extracted pattern as to which line segment in directions the pixel is positioned on, and an encoding unit for encoding the extracted pattern by selecting a template having an optimum form according to the result of the line segment checking. The codes in pattern matching encoding are reduced, and the efficiency of code transmission and code accumulation is improved.

Abstract: A method for transcoding a compressed video partitions the compressed video into hierarchical levels, and extracts features from each of the hierarchical levels. One of a number of conversion modes of a transcoder is selected dependent on the features extracted from the hierarchical levels. The compressed video is then transcoded according to the selected conversion mode.

Abstract: Video compression coding with partitioning of data into motion vector data and texture data with reversible Golomb-Rice type codes for the data. Resynchronization markers separate the data types, and the reversible coding permits decoding in both forward and backward directions to minimize data discarded due to errors.

Abstract: A video compression method of estimating a motion vector representative of a difference between a reference frame and a current frame is described. Typically, both the reference frame and the current frame include background and foreground data. In the method a block of the current frame is selected for analysis, and a determination is made whether the block selected is a foreground block or a background block. If the block is a foreground block, then it is compared with predetermined search points in the reference frame. On the other hand, if the block is a background block, it is compared with predetermined search points in only a portion of the reference frame.

Abstract: If a signal is repeatedly encoded and decoded, coding noise generally accumulates as it passes through the various coding systems. The present system provides means for preventing this, by providing means for identifying, at the second coding system, which coding system was previously used. The second coding can then use the same system as the previous coding. This use of matching coding systems results in very little extra coding noise being introduced by the second coding. The input signal is coded by two different encoders 11 and 12, their outputs are decoded and compared with the input signal at 20 and 21, the differences accumulated at 22 and 23. The smaller of the differences is used by selector 13 to select the encoder which matches the previous coding of the signal. The principles can be extended to MPEG Layer II Audio Coding and similar block coding systems.

Abstract: An image coding apparatus inputs pixel data of a part image of high resolution. An upper layer coding portion (101), a second shape data generating portion (102), and a second shape data coding portion (103) perform coding of shape data and pixel data in the upper layer. A down sampling portion (104) generates pixel data of low resolution. A lower layer coding portion (105), a first shape data generating portion (106), and a first shape data coding portion (107) code shape data and pixel data in the lower layer.

Abstract: Fractional parts of quantized video coefficients are used as enhancement layers when encoding a video steam. This use of the fractional parts allows the reuse of decoding components.

Abstract: Optical flow is calculated for each sub-block on the basis of two images, the sub-blocks are then partitioned into a region having low confidence and a region having high confidence depending on the reliability of the optical flow, and the optical flow in the region having low confidence is filled by dilation processing using the optical flow in its surrounding regions.

Abstract: In a method for coding a moving picture image, in which the moving picture image is coded into a digital moving picture stream when the moving picture image is transmitted via a network, the moving picture image is coded in such a manner that a data unit including a synchronous signal corresponds or conforms to a data transmission unit on the network, or, the moving picture image is coded in such a manner that a synchronous signal is included in a position near a head of respective data transmission units on the network. Therefore, in the digital moving picture stream generated according to the invention, the header of the synchronous layer is included in every maximum length of the IP packet in the variable length packet switching method and in every size of the time slots in the variable bit rate TDM.

Abstract: A system for coding video data comprised of one or more frames codes a portion of the video data using a frame-prediction coding technique, and generates residual images based on the video data and the coded video data. The system then codes the residual images using a fine-granular scalability coding technique, and outputs the coded video data and at least one of the coded residual images to a receiver.

Abstract: A bit-plane processor reads out a code block, which serves as a unit for arithmetic coding, from an SRAM. After converting the code block to the form of a bit-plane, the bit-plane processor supplies bit data to a pass processor. The pass processor includes an s pass processor, an r pass processor and a c pass processor. Each of s pass, r pass and c pass processings are executed in parallel in a state such that start time thereof is shifted by a predetermined unit time by operation of two delay units.

Abstract: When a background interpolation-judging section 107 judges that parts areas of a lower layer and an upper layer move significantly, and a visual effect can be obtained by the background interpolation, a controller 103 controls a switch 104 based on the area information of the parts area of the lower layer to perform the background interpolation. A weighted average section 106 takes an average by weighting to the upper layer and the lower layer by using the interpolated background to generate an interpolated image. By using this interpolated image, the prediction-encoding/decoding of the upper layer is performed. On the contrary, when the background interpolation-judging section 107 judges that parts areas do not move so significantly, and a visual effect cannot be obtained by the background interpolation, a background is synthesized by using the output of the interpolated image-forming section 105 to generate an interpolated image.

Abstract: A system and a method for encoding, transmitting, decoding and storing a high-resolution video sequence using a low-resolution base layer and a higher-resolution enhancement layer. The base layer contains low-resolution video information and is compressed in a manner such that it can be decoded independently of the enhancement layer. The base layer may be encoded in an existing standard video format (such as MPEG-2). The enhancement layer, which contains high-resolution information, provides a variable amount of enhancement to the base layer. The compressed video sequence is transmitted in two layers and uses a minimum amount of bit rate by using information transmitted in the base layer in the decoding of both the base layer and the enhancement layer. In an enhanced decoder, both the base layer and the enhancement layer use this information that has been transmitted in the base layer.

Abstract: A motion picture coding and decoding apparatus synthesizes a lower layer frame at a certain time by using first component area information of a lower layer preceding in the time and second component area information of a lower layer succeeding in the time. For an area where the first and second component areas overlapped, or for an area which is neither the first nor the second component area on the lower layer frame, lower layer frames preceding and succeeding in time are subjected to weighted average for synthetisization. For the area corresponding to the first component area only, the lower layer frame succeeding in time is used, and for the area corresponding to the second component area only on the synthesized lower layer frame, the lower layer frame preceding in time is used, for synthesizing the lower layer.

Abstract: A system for coding video data comprised of one or more frames codes a portion of the video data using a frame-prediction coding technique, and generates residual images based on the video data and the coded video data. The system then codes the residual images using a fine-granular scalability coding technique, and outputs the coded video data and at least one of the coded residual images to a receiver.

Abstract: When vocoder-bypass communication is performed between a first mobile station on a voice transmitting side and a second mobile station on a receiving side, the first mobile station transmits voice data the compression rate of which has been reduced periodically. As a result, a vacant space is reserved periodically in a traffic frame transmitted from a base station controller on the receiving side to the second mobile station on the receiving side. When it becomes necessary to transmit signaling data, a signaling multiplexer of the base station controller transmits the signaling data upon multiplexing it into the vacant space of the traffic frame.

Abstract: A compressed bitstream is scaled down to a reduced rate bitstream by first demultiplexing a compressed input bitstream to extract video objects as elementary input bitstreams having a first bit rate. A transcoder converts each elementary input bitstream to an elementary output bitstream having a second bit rate. The first bit rate is less than the second bit rate. A transcoding control unit, coupled to the transcoder, supplies control information for the transcoder. A multiplexer composes the elementary output bitstreams into a compressed output bitstream having the second bit rate.

Abstract: A moving picture coding/decoding method and apparatus having a spatially scalable architecture and a signal-to-noise ratio (SNR) scalable architecture together is provided.

Abstract: In an apparatus for transcoding a compressed video, a generator simulates constraints of a network and constraints of a user device. A classifier is coupled to receive an input compressed video and the constraints. The classifier generates content information from features of the input compressed video. A manager produces a plurality of conversions modes dependent the constraints and content information, and a transcoder produces output compressed videos, one for each of the plurality conversion modes.

Abstract: The present invention provides methods and systems to determine the frequency weighting matrix that will provide the best image quality during MPEG4 FGS enhancement layer encoding, and to change this determination on a scene characteristics change basis, thereby optimizing the resulting output picture quality, especially in bandwidth-deprived applications.

Abstract: The invention relates to scalable video encoders, and, more precisely, to an encoder comprising a base layer and at least an enhancement layer circuit, said circuits being capable of generating enhancement layer video data associated with compressed base layer video data and suitable for transmission to a video decoder. In said encoder, the implemented encoding method, based on a hierarchical triangular mesh representation to which a matching pursuit error coding step is specifically adapted, comprises a base layer encoding step and enhancement layer encoding steps.

Abstract: A motion picture coding and decoding apparatus synthesizes a lower layer frame at a certain time by using first component area information of a lower layer preceding in the time and second component area information of a lower layer succeeding in the time. For an area where the first and second component areas overlapped, or for an area which is neither the first nor the second component area on the lower layer frame, lower layer frames preceding and succeeding in time are subjected to weighted average for synthetisization. For the area corresponding to the first component area only, the lower layer frame succeeding in time is used, and for the area corresponding to the second component area only on the synthesized lower layer frame, the lower layer frame preceding in time is used, for synthesizing the lower layer.

Abstract: The invention relates to a video coding method based on an adaptive frame/field encoding mode. In order to avoid an impairment of the image quality and of the compression efficiency when a video sequence comprises a lot of motion or on the contrary quasi-motionless images, an improved real time double pass encoding scheme is proposed: during the first pass, no video stream is generated, but statistical results are computed and then provided to the second pass in order to optimize during said second pass the bit rate allocation and the buffer management. This improved double pass encoding method leads to an increase of the compression efficiency of about 10%.

Abstract: In the transmission of moving images in accordance with an MPEG, H.261, or H.263 standard, a region that satisfies a predetermined criterion of the image that is to be transmitted is coded with a higher image quality than the rest of the image. The region satisfies the criterion when it has a predetermined color, preferably a color similar to human skin. The higher image quality of the region that satisfies the criterion is guaranteed by a lower quantization value, a higher topical resolution, or a higher repetition rate.

Abstract: A video signal coding apparatus comprises a divider 102 that divides an input digital video signal into an effective area and an additional area, an effective-area blocking device 103 for dividing the effective area into effective blocks, an effective-area encoder 104 that hight-efficiency-codes the effective blocks to create effective compressed blocks, an additional-area encoder 105 that hight-efficiency-codes the additional area to create additional compressed data, an additional-area blocking device 106 for dividing the additional compressed data into additional compressed blocks each a luminance signal for a plurality of pixels and at least one color difference signal for pixels arranged at the same position as the plurality of pixels, and a substitution device 107 that substitutes the additional compressed blocks for data in the same effective compressed blocks at predetermined positions.

Abstract: The present invention is directed to a technique for flexibly and efficiently coding of video data. The technique involves coding of a portion of the video data called base layer frames and coding of residual images generated from the video data and the prediction signal. The prediction for each video frame is generated using multiple decoded base layer frames and may use motion compensation. The residual images are called enhancement layer frames and are then coded. Based on this technique, since a wider locality of base layer frames are utilized, better prediction can be obtained. Since the resulting residual data in enhancement layer frames is small, they can be efficiently coded. For coding of enhancement layer frames, fine granular scalability techniques (such as DCT transform coding or wavelet coding) are employed. The decoding process is reverse of encoding process. Therefore, flexible, yet efficient coding and decoding of video is accomplished.

Abstract: The invention relates to a method for encoding a video sequence subdivided into groups of frames. This method comprises an on-line procedure in which a three-dimensional wavelet decomposition is performed involving a biorthogonal filter bank in a lifting scheme using optimal weighting constants. These constants are determined thanks to an additional off-line procedure in which a similar decomposition is performed but without any weighting constants.

Abstract: The MPEG-4 video standard includes a predictive coding scheme. When a scene-cut occurs in the sequence processed by said coding scheme, the first video object plane (VOP) which follows it is coded as an I-VOP, instead of predicting it from the previous VOP, completely different. In case of temporal scalability, when the scene-cut occurs between two VOPs of the enhancement layer, specific rules for selecting the temporal reference(s) during the prediction operations in said enhancement layer are defined.

Abstract: A CODEC system for spatially scalable video data includes a decimate unit for performing DCT-based down-sampling with respect to macro block data of input video data to produce decimated block data representing low frequency part of the macro block data, a first encoder for encoding the decimated block data to produce base layer DCT data having DCT coefficients representing the low frequency part, a first decoder for decoding the base layer DCT data from the first encoder to produce base layer block data, an interpolate unit for performing DCT-based interpolation with respect to the base layer block data from the first decoder to produce interpolated base layer block data, a second encoder for encoding enhancement layer block data obtained from the macro block data and the interpolated base layer block data to produce enhancement layer DCT data wherein the enhancement layer block data representing high frequency part of the macro block data, and a second decoder for decoding the enhancement layer DCT data fro

Abstract: The invention relates to a method of decoding a video bitstream including base layer and enhancement layer coded video signals, said method comprising the steps of decoding the base layer and enhancement layer coded video signals to produce decoded base layer frames and decoded enhancement layer frames, and displaying the decoded base layer frames either alone or with the decoded enhancement layer frames. According to the invention, each poor quality frame of the base layer to be displayed is replaced by an frame obtained either by means of an interpolation between the two frames of the enhancement layer preceding and following said poor quality frame of the base layer or by only one of these two frames, for example the temporally closest one.

Abstract: The invention, provided for an implementation, in a video encoder with base layer coding means and enhancement layer coding means, relates to a method of coding the video objects (VOs) of a sequence according to the following steps : segmentation of the sequence, and coding operation of the texture and shape of said VOs. According to a preferred embodiment, the texture coding operation itself comprises motion compensated prediction operations, during which the temporal references of the enhancement layer VO planes (VOPs) of type P or B are selected only on a temporal distance criterion, without any consideration of the layer they belong to.

Abstract: The motion data preparation system provides a motion data preparation system which can acquire stable motion data by detecting color markers without being affected by the surrounding brightness, and which is enabled to execute high-speed, accurate processing by reducing the amount of information on color image data. Color representations of about 16770 thousands of colors for a 24-bit input image are integrated and divided for each color camera, and outputted as 256 kinds of color group signals by look-up table memory circuits 125, 126. Thus, the amount of information is consolidated to about 1/60000, allowing a simple, fast calculation to be realized. Further, the color representation is, separated into luminance (Y) and chroma, for example, red color difference (R-Y) and blue color difference (B-Y), and the chromatic component is corrected by luminance. As a result, errors due to effects of variations in illumination conditions and the like can be reduced.