Abstract: In a sinusoidal audio encoder a number of sinusoids are estimated per audio segment. A sinusoid is represented by frequency, amplitude and phase. The invention uses a track dependent quantization of phase. A track is encoded with a suitable initial (e.g. frequency dependent) quantization grid that is chosen among a set of possible initial grids that may vary from fine to coarse. If, in a series of time segments the frequency variation in a particular track is smaller than a predetermined value, the track is quantized using a finer quantization grid. The invention gives a significant improvement in decoded signal quality, especially for low bit-rate quantizers.

Abstract: A method and system including an improved generalized reference decoder that operates according to any number of sets of rate and buffer parameters for a given bit stream. Each set characterizes a leaky bucket model and contains three parameters representing the transmission bit rate, buffer size, and initial decoder buffer fullness. An encoder provides at least two sets of these parameters, whereby the decoder selects one or interpolates between them to operate at any desired peak bit rate, buffer size or delay. The generalized reference decoder may select the smallest buffer size and corresponding delay that decodes the bit stream without buffer underflow or overflow, or alternatively may select and operate at the minimum required peak transmission rate, or something between both. In practice, the buffer size, delay and/or the peak transmission rate can be reduced by significant factors, and/or the signal-to-noise ratio (SNR) can be increased.

Abstract: An image coding apparatus includes a variable length coding section, an arithmetic coding section and a common buffer memory. The variable length coding section inputs image data and outputs a binarized code sequence applied with variable length coding. The arithmetic coding section applies arithmetic coding to the binarized code sequence outputted from the variable length coding section. The common buffer memory transmits and receives data between the variable length coding section and the arithmetic coding section.

Abstract: The invention provides systems and methods for providing compressed video data from multiple bit streams. The systems and methods apply a two-stage strategy. In the first stage, a conditioning step is performed on a bit stream comprising compressed video data which outputs a conditioned bit stream that is able to receive digital insertions without subsequent decompression of the compressed video data or removal from network packets. The conditioning includes recoding an incoming bit stream such that compressed video data in the bit stream immediately before and after a splice point does not have temporal reliance across the splice point. In the second stage, e.g., at a downstream network device, splicing of compressed video data from a second bit stream into the conditioned bit stream is performed. The splicing takes advantage of the changes made to the conditioned bit stream and may occur at the network packet level.

Abstract: A method and system of lossless adaptive Golomb/Rice (G/R) encoding of integer data using a novel backward-adaptive technique having novel adaptation rules. The adaptive G/R encoder and decoder (codec) and method uses adaptation rules that adjust the G/R parameter after each codeword is generated. These adaptation rules include defining an adaptation value and adjusting the G/R parameter based on the adaptation value. If the adaptation value equals zero, then the G/R parameter is decreased by an integer constant. If the adaptation value equals one, then the G/R parameter is left unchanged. If the adaptation value is greater than one, then the G/R parameter is increased by the adaptation value. In addition, the adaptive G/R encoder and method include fractional adaptation, which defines a scaled G/R parameter in terms of the G/R parameter and updates and adapts the scaled G/R parameter to slow down the rate of adaptation.

Abstract: A method comprises determining a plurality of time intervals Tp and Tn within a variable bit rate (VBR) representation of an image sequence. The time intervals Tp are those in which a number of blocks of information per unit time is greater than a baseline value. The time intervals Tn are those in which a number of blocks of information per unit time is less than the baseline value. A second representation of the image sequence is created in which some blocks of information Bp are removed from the time intervals Tp and interlaced with blocks of information Bn in the time intervals Tn to reduce a variation in a number of blocks of information per unit time between the time intervals Tp and Tn.

Abstract: The present embodiments disclose methods and apparatus for transcoding video data. A method for transcoding video data may include: performing variable length decoding on an input bit stream; determining a bit stream part that can be transmitted transparently and a bit stream part that cannot be transmitted transparently according to an original compression protocol, a target compression protocol, and relevant bit stream parameters; decompressing the bit stream part that cannot be transmitted transparently according to the original compression protocol and compressing the decompressed bit stream according to the target compression protocol; combining the bit stream part that can be transmitted transparently and the compressed bit stream part that cannot be transmitted transparently; and performing variable length coding on the combined bit stream to generate an output bit stream. This greatly decreases the calculation workload of the transcoder, speeds up transcoding, and ensures real-time image transmission.

Abstract: A system and process for compressing and decompressing multiple video streams depicting substantially the same dynamic scene from different viewpoints. Each frame in each contemporaneous set of video frames of the multiple streams is represented by at least a two layers—a main layer and a boundary layer. Compression of the main layers involves first designating one or more of these layers in each set of contemporaneous frames as keyframes. For each set of contemporaneous frames in time sequence order, the main layer of each keyframe is compressed using an inter-frame compression technique. In addition, the main layer of each non-keyframe within the frame set under consideration is compressed using a spatial prediction compression technique. Finally, the boundary layers of each frame in the current frame set are each compressed using an intra-frame compression technique. Decompression is generally the reverse of the compression process.

Abstract: This disclosure describes techniques for generating a layered encoded bitstream structure that exploits correlation in header information among video blocks of a coded unit of video data. A video encoder configured to operate in accordance with the techniques of this disclosure separates header information of the video blocks of a slice (or other coded unit) from the residual information of the video blocks of the slice. The video encoder run-length encodes the header information of the video blocks to better exploit the correlation of the header information among the blocks of the slice. After encoding the header information of the blocks of the slice, the video encoder encodes the residual information for each of the blocks of the slice. The video encoder transmits the encoded header information as a first sequence of bits and transmits the encoded residual information as second sequence of bits.

Abstract: A system is described that comprises a method and apparatus for further compressing an already compressed data stream, using a mathematical exclusive-OR computation. The method comprises: receiving a data stream that has been compressed using a first compression protocol; decompressing the data stream using the first compression protocol; reducing temporal redundancy in the data stream using an exclusive-OR comparison protocol; and recompressing the data stream using the first compression protocol. The apparatus comprises: a decompression unit to receive and decompress a compressed data stream to produce decompressed data; an exclusive-OR comparison unit, coupled to the decompression unit, to perform a mathematical exclusive-OR operation on the decompressed data to produce resultant data; and a recompression unit to compress the resultant data to produce a further compressed data stream.

Abstract: Provided is a video encoding rate controlling method based on the length of a Transport Stream (TS) packet in a video coding apparatus, the method including the steps of: a) setting up an initial target bit quantity for a picture to be coded; b) calculating a length of a payload used to packetize a coded picture into TS packets; c) adjusting the target bit quantity based on the length of the payload; and d) controlling a rate based on the adjusted target bit quantity in the step c).

Abstract: A system and method for processing of video content containing redundant pixels using the picture recombination technique, with one of the main application in video transcoding process. The picture recombination process employs a quality ranking criterion to adaptively select the best region from the co-located regions of redundant pictures as the region for output. An approximation for quality ranking between a decoded picture region and an original picture region has been developed to guide the selection for recombination because the original picture is not available to the transcoder. The quality ranking formula is further modified as a simple linear function depending on the quantization scale, the bit count, and complexity measure of the region.

Abstract: A method and system for enabling trick plays during a variable bit rate (VBR) playback of a media file transmitted to a user media device as a constant bit rate (CBR) flow includes determining a plurality of access points within the media file. The media file is configured to be played back from each of the plurality of access points. A minimum buffer value is calculated for each of the plurality of access points. The minimum buffer value identifies a minimum amount of the media file to transmit to the user media device before beginning playback of the media file from each of the plurality of access points to substantially ensure that the media file is configured to be played back from each of the plurality of access points continuously and uninterruptedly at a variable bit rate.

Abstract: A method and apparatus for variable accuracy inter-picture timing specification for digital video encoding is disclosed. Specifically, the present invention discloses a system that allows the relative timing of nearby video pictures to be encoded in a very efficient manner. In one embodiment, the display time difference between a current video picture and a nearby video picture is determined. The display time difference is then encoded into a digital representation of the video picture. In a preferred embodiment, the nearby video picture is the most recently transmitted stored picture. For coding efficiency, the display time difference may be encoded using a variable length coding system or arithmetic coding. In an alternate embodiment, the display time difference is encoded as a power of two to reduce the number of bits transmitted.

Abstract: A method and apparatus for variable accuracy inter-picture timing specification for digital video encoding is disclosed. Specifically, the present invention discloses a system that allows the relative timing of nearby video pictures to be encoded in a very efficient manner. In one embodiment, the display time difference between a current video picture and a nearby video picture is determined. The display time difference is then encoded into a digital representation of the video picture. In a preferred embodiment, the nearby video picture is the most recently transmitted stored picture. For coding efficiency, the display time difference may be encoded using a variable length coding system or arithmetic coding. In an alternate embodiment, the display time difference is encoded as a power of two to reduce the number of bits transmitted.

Abstract: Methods and apparatuses for blending two images using vector table look up operations. In one aspect of the invention, a method to blend two images includes: loading a vector of keys into a vector register; converting the vector of keys into a first vector of blending factors for the first image and a second vector of blending factors for the second image using a plurality of look up tables; and computing an image attribute for the blended image using the blending factors.

Abstract: Provided are video encoding and decoding methods and apparatuses for encoding a video by variably selecting one from two or more difference color formats. Accordingly, by using at least one of channel state information and a result of encoding a video in a predetermined encoding unit encoded in advance, whether or not to convert a video in a current encoding unit of an input RGB (red, green, blue) color format into a YCbCr color format is adaptively determined to perform encoding. Therefore, a video with uniform quality corresponding to a channel environment having a variable bit-rate can be provided.

Abstract: An entropy coding module is provided for use in a video encoder that encodes a video input signal based on a plurality of macroblocks derived from the video input signal. The entropy coding module includes an entropy coder that generates entropy encoded data from discrete transformed coefficients for the plurality of macroblocks. A neighbor management module stores neighbor data for at least one macroblock of the plurality of macroblocks for retrieval by the entropy encoder, when operating on at least one neighboring macroblock of the plurality of macroblocks.

Abstract: A VSB communication system or transmitter for processing supplemental data packets with MPEG-II data packets includes a VSB supplemental data processor and a VSB transmission system. The VSB supplemental data processor includes a Reed-Solomon coder for coding the supplemental data to be transmitted, a null sequence inserter for inserting a null sequence to an interleaved supplemental data for generating a predefined sequence, a header inserter for inserting an MPEG header to the supplemental data having the null sequence inserted therein, a multiplexer for multiplexing an MPEG data coded with the supplemental data having the MPEG header added thereto in a preset multiplexing ratio and units. The output of the multiplexer is provided to an 8T-VSB transmission system for modulating a data field from the multiplexer and transmitting the modulated data field to a VSB reception system.

Abstract: A method comprises determining a plurality of time intervals Tp and Tn within a variable bit rate (VBR) representation of an image sequence. The time intervals Tp are those in which a number of blocks of information per unit time is greater than a baseline value. The time intervals Tn are those in which a number of blocks of information per unit time is less than the baseline value. A second representation of the image sequence is created in which some blocks of information Bp are removed from the time intervals Tp and interlaced with blocks of information Bn in the time intervals Tn to reduce a variation in a number of blocks of information per unit time between the time intervals Tp and Tn.

Abstract: A flag indicating whether a decoding process is completed or continued is disposed in each of entries of a decoding process table. A decoded value and a significant bit length are recorded in the entry of a decoding process completion. Information for identifying the decoding process table which is used in a subsequent process, and a bit length that is clipped from a code word which is used when referring to a subsequent table are recorded in the entry of the decoding process continuation. When the decoding process starts, the information for identifying the table to be used and the bit length that is referred to from the code word when referring to the table are designated together with the code word. The decoding process table reference is repeated as the occasion demands. With the above configuration, there is provided a variable length code decoding device.

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

Abstract: Methods, medium, and machines which compress, encode, enhance, transmit, decompress and display digital video images in real time. Real time compression is achieved by sub-sampling each frame of a video signal, matching the illumination intensity value representing each pixel with a line number, incrementing a repeat counter, and encoding a repeat data structure with the repeat counter and line number data structure with the line number forming a compressed stream of data. Real time transmission of video images is achieved due to high levels of effective compression. Real time decompression is achieve by decoding and decompressing the encoded data to display high quality images. High levels of effective compression also reduce the storage space requirement for recorded video.

Abstract: An entropy encoder includes an apparatus for producing a data stream which comprises two reference points, of code words of variable lengths, the apparatus comprising a first device for writing at least a part of a code word into the data stream in a first direction of writing, starting from a first reference point, and a second device for writing at least a part of a code word into the data stream in a second direction of writing, which is opposite to the first direction of writing, starting from the other reference point. In particular, when a raster having a plurality of segments is used to write the code words of variable lengths into the data stream, the number of the code words which can be written starting at raster points is doubled, in the best case, such that the data stream of code words of variable lengths is robust toward a propagation of sequence errors.

Abstract: A VSB communication system or transmitter for processing supplemental data packets with MPEG-II data packets includes a VSB supplemental data processor and a VSB transmission system. The VSB supplemental data processor includes a Reed-Solomon coder for coding the supplemental data to be transmitted, a null sequence inserter for inserting a null sequence to an interleaved supplemental data for generating a predefined sequence, a header inserter for inserting an MPEG header to the supplemental data having the null sequence inserted therein, a multiplexer for multiplexing an MPEG data coded with the supplemental data having the MPEG header added thereto in a preset multiplexing ratio and units. The output of the multiplexer is provided to an 8T-VSB transmission system for modulating a data field from the multiplexer and transmitting the modulated data field to a VSB reception system.

Abstract: This disclosure describes scalable video coding techniques. In particular, the techniques may be used to encode refinements of a video block for enhancement layer bit streams in a single coding pass, thereby reducing coding complexity, coding delay and memory requirements. In some instances, the techniques encode each nonzero coefficient of a coefficient vector of the enhancement layer without knowledge of any subsequent coefficients. Coding the enhancement layer in a single pass may eliminate the need to perform a first pass to analyze the coefficient vector and a second pass for coding the coefficient vector based on the analysis.

Abstract: A method for processing a variable length code comprising: determining a first address; decoding opcodes from the at least one table starting at a first address; in response to each of the opcodes: receiving a portion of a sequence of bits, the sequence of bits comprising a first variable length code; receiving S from the second table at the current address; flushing S bits in the sequence of bits; receiving T corresponding to one of the stages; determining a value of a set of T bits in the sequence of bits; receiving D from the second table at the current address; and computing the next address, the next address being the sum of the current address, D, and the value of the set of T bits; and retrieving the next opcode, the next opcode being retrieved from the next address; and determining the decoded syntax element.

Abstract: A method comprises determining a plurality of time intervals Tp and Tn within a variable bit rate (VBR) representation of an image sequence. The time intervals Tp are those in which a number of blocks of information per unit time is greater than a baseline value. The time intervals Tn are those in which a number of blocks of information per unit time is less than the baseline value. A second representation of the image sequence is created in which some blocks of information Bp are removed from the time intervals Tp and interlaced with blocks of information Bn in the time intervals Tn to reduce a variation in a number of blocks of information per unit time between the time intervals Tp and Tn.

Abstract: A data compression method improves Lempel-Ziv (“LZ”) compression by encoding the offsets produced during LZ compression as variable-bit-length (“VBL”) encoded integers, and outputting the VBL integers as part of the compressed data. Other integers produced during LZ compression, as well as integers produced by other data compression algorithms, can also be encoded using a VBL scheme.

Abstract: A moving image distribution system of the present invention is a moving image distribution system for distributing one or more streams through a transmission path 104 and a transmission path 105 to a terminal 103, and has a converter configured to posting a predetermined capability information to the terminal 103 side, and receiving at least one stream from a delivery server 801 having streams stored therein, or receiving a plurality of streams from a plurality of delivery servers 801, and converting a syntax of the streams so as to adapt it to the capability information, and the sending them through the transmission path 105 to the terminal 103.

Abstract: A transport stream (TS) generating apparatus, a transmitting apparatus, a receiving apparatus, a digital broadcast system having the above, and a method thereof are provided. The digital broadcast system includes a transport stream (TS) generating apparatus which generates a multi transport stream (TS) by multiplexing a normal stream and a turbo stream having a variable coding rate, a transmitting apparatus which re-constructs the multi TS by processing the turbo stream, and transmits the re-constructed multi TS, and a receiving apparatus which receives the re-constructed multi TS, and decodes the normal stream and the turbo stream respectively, to recover normal data and turbo data. Accordingly, a multi TS, which includes normal stream and a turbo stream of various coding rates, can be transmitted and received efficiently.

Abstract: A flexible length decoder including a plurality of data filter units and a control unit is provided. The data filter units perform a comparing operation on a data stream according its corresponding pattern and output a comparing result. The control unit controls the configurations of the data filter units. If the space of any one of the data filter units for storing the pattern is not enough to record the required pattern, the control unit combines two or more data filter units into an equivalent data filter unit, such that the equivalent data filter unit stores the pattern and performs the comparing operation.

Abstract: A method, a component, a system, and a computer program for changing an encoding mode of an encoded data stream from a first encoding mode to a second encoding mode are disclosed. The encoded data stream at the first encoding mode is represented by first encoding parameters. For the encoding mode change the steps of selecting (20) a first set of the first encoding parameters to be used unchanged at the second encoding mode, selecting (30) a second set of the first encoding parameters, changing (40) the second set according to an algorithm being adapted to change the second set to match to the second encoding mode when combined with the first set, and combining (50) the first set and the changed second set for representing the encoded data stream by second encoding parameters at the second encoding mode are performed.

Abstract: A method and apparatus for encoding high dynamic range video by means of video compression is shown.

Abstract: A method of operation within an integrated circuit device having a plurality of processing lanes. A first sub-stream of data, having a variable length, is generated in a first one of the processing lanes. A second sub-stream of data, also having a variable length, is generated in a second one of the processing lanes. The first and second sub-streams are then output to form a single bitstream.

Abstract: A hybrid block matching prediction and transform based n dimensional signal sequence encoder, including an encoder motion estimator, having a cost function. A first embodiment includes an entropy-based cost function. A second embodiment includes a fast block matching search (motion estimation) method to learn the results from neighboring blocks and perform a large range search with only a small number of points to visit. A third embodiment includes a method to dynamically adjust the cost function parameters and other selected coding control parameters based on encoder outputs to optimize the quality and performance of the encoder. A fourth embodiment includes a method to enable exploring and rapid processing of fractional grid points for n dimensional block matching search (motion estimation). A fifth embodiment includes a hybrid block matching prediction and transform-based n dimensional signal sequence decoder.

Abstract: A low-complexity method for prevention of H.264 start code emulation by bit-handling routines with additional functionality. The low-complexity is achieved by employing a start code pre-determination scheme, which saves bitstream handling complexity by about 50% and 30% on the encoder and decoder sides, respectively. The start code emulation prevention has been embedded into the low-level bitstream handling routines. By doing so it avoids the use of the second bitstream buffer, maintains the decoder ability of using a circular bitstream buffer, and satisfies the BURST-aligned SDRAM access requirement.

Abstract: Techniques and tools for escape mode code resizing are described. For example, a video decoder receives encoded information (e.g., runs, levels) for transform coefficients of blocks. For at least some of the encoded information, the decoder decodes in an escape mode for which codes have sizes signaled on a sub-frame basis (e.g., on a per-interlaced field basis in a video frame, or on a per-slice basis in a video frame). A video encoder performs corresponding encoding and signaling.

Abstract: An image coding apparatus includes a variable length coding section, an arithmetic coding section and a common buffer memory. The variable length coding section inputs image data and outputs a binarized code sequence applied with variable length coding. The arithmetic coding section applies arithmetic coding to the binarized code sequence outputted from the variable length coding section. The common buffer memory transmits and receives data between the variable length coding section and the arithmetic coding section.

Abstract: An exemplary embodiment of the invention relates to a method of using pattern vectors for image coding and decoding. The method comprises converting a block of image data into a set of transform coefficients, quantizing the transform coefficients such that a number of the coefficients become zero, constructing a single entity or bit vector indicating which coefficients are non-zero, coding the single entity or bit vector as an integer using an adaptive, semi-adaptive or non-adaptive arithmetic coder, coding the values of the coefficients in any fixed order, using an adaptive, semi-adaptive or non-adaptive arithmetic coder, or some other coder, and coding all coefficients except the zero coefficients. The system and method of decoding data relate to the corresponding hardware and process steps performed by the decoder when decoding a bitstream coded as described herein.

Abstract: The techniques and mechanisms described herein are directed to a system for stylizing video, such as interactively transforming video to a cartoon-like style. Briefly stated, the techniques include determining a set of volumetric objects within a video, each volumetric object being a segment. Mean shift video segmentation may be used for this step. With that segmentation information, the technique further includes indicating on a limited number of keyframes of the video how segments should be merged into a semantic region. Finally, a contiguous volume is created by interpolating between keyframes by a mean shift constrained interpolation technique to propagate the semantic regions between keyframes.

Abstract: A variable bit rate (VBR) representation of an image sequence is segmented based on a plurality of time intervals. For each of at least two of the time intervals, the method comprises: determining which of the packets, denoted by Pp, in the VBR representation within the presently-considered time interval has a number of blocks of information per unit time greater than a baseline value; determining which of the packets, denoted by Pn, in the VBR representation within the presently-considered time interval has a number of blocks of information per unit time less than the baseline value; and creating a second representation of the image sequence in which some blocks of information Bp are removed from at least one Pp packet and interlaced with blocks of information in at least one Pn packet to produce reformatted packets.

Abstract: An image processing apparatus performs variable-length compression on the image data of each block included in one page, and adds a bit to the resultant code data of each block to make it have a constant data length. The apparatus stores the data length of the added bit. On the other hand, the apparatus stores a variable-length code from which the added bit is erased in a storage. If it is determined that respective bits are added to all blocks to make them have the constant data length, the apparatus adds respective bits of different data lengths to variable-length codes read from the storage, thereby converting the data lengths of the blocks into a shorter constant data length than the constant data length.

Abstract: Presented herein are system(s), method(s), and apparatus for decoding exponential Golomb codes. In one embodiment, there is presented a system for decoding codes having lengths (L) and information bits. The system comprises a circuit and a multiplexer. The circuit provides the information bits of the codes. The multiplexer provides values for the codes, the values for the codes being a function of 2trunc(L/2).

Abstract: A variable length coding method is provided for coding coefficients in each block which are obtained by performing frequency transformation on picture data of a moving picture per block having a predetermined size, and includes: a coefficient scanning step of scanning the coefficients in the block in a predetermined order; and a coding step of coding the coefficients scanned in the coefficient scanning step into variable length codes in a predetermined order by switching a plurality of tables to be used for coding. Here, a direction of switching between the tables may be one-directional. Also, the coding may be non-arithmetic coding.

Abstract: A method for selectively reducing quantization levels is adapted for use in a transcoder including a variable length decoding unit. The variable length decoding unit decodes a plurality of input variable length codes into a plurality of decoded pairs, wherein each decoded pair is a run-level pair. The method includes the following steps: (a) obtaining a plurality of absolute levels arranged in an order of scan positions according to the runs and levels of the decoded pairs; (b) determining whether a saved bit number correspondingly found by reducing each absolute level exceeds a bit number threshold value such that, if yes, the respective absolute level belongs to a target set; and (c) reducing each absolute level that belongs to the target set.

Abstract: A variable length coding method is provided for coding coefficients in each block which are obtained by performing frequency transformation on picture data of a moving picture per block having a predetermined size, and includes: a coefficient scanning step of scanning the coefficients in the block in a predetermined order; and a coding step of coding the coefficients scanned in the coefficient scanning step into variable length codes in a predetermined order by switching a plurality of tables to be used for coding. Here, a direction of switching between the tables may be one-directional. Also, the coding may be non-arithmetic coding.

Abstract: A variable length coding method is provided for coding coefficients in each block which are obtained by performing frequency transformation on picture data of a moving picture per block having a predetermined size, and includes: a coefficient scanning step of scanning the coefficients in the block in a predetermined order; and a coding step of coding the coefficients scanned in the coefficient scanning step into variable length codes in a predetermined order by switching a plurality of tables to be used for coding. Here, a direction of switching between the tables may be one-directional. Also, the coding may be non-arithmetic coding.

Abstract: The digital video encoder or video decoder with referencing frame image compression and decompression mechanism allows a smaller on-chip referencing frame storage device and efficient off-chip referencing frame random access. In using the off-chip frame buffer, a predetermined amount of line buffer temporarily saves the compressed pixels and reconstructs the needed macro-block pixels according to the motion vector for motion compensation in video decoder and reconstructs the searching range pixels for motion estimation in video encoder.