Patent application number | Description | Published |
20080240242 | Method and system for motion vector predictions - A video coding system is capable of encoding and/or decoding a video frame based on at least two different types of motion vector predictions. In one type, the motion vector predictor of a current block in the video frame is calculated using only the motion vector of a neighboring block which is directly above the current block. In another type, the motion vector predictor is calculated using the motion vector of a neighboring block which is located on the left side of the current block. In the former type, adjacent blocks located in the same row can be decoded independently of each other. In the latter type, adjacent blocks located in the same column can be decoded independently. The system may also be capable of conventional coding. An indication is used for indicating to the decoder side which type of motion vector predictor is used in the encoding. | 10-02-2008 |
20080253459 | HIGH ACCURACY MOTION VECTORS FOR VIDEO CODING WITH LOW ENCODER AND DECODER COMPLEXITY - Two-stage interpolation can be provided for frame prediction samples with quarter-pixel and finer accuracy. All samples of quarter-pixel and finer accuracy can use either half or full/integer-pixels in a bi-linear interpolation to allow for the use of higher accuracy motion vectors, such as one-eighth-pixel accuracy motion vectors. The motion vectors can be restricted in a manner such that they are not allowed to point to every possible sub-pixel sample on a sub-pixel grid, but rather a subset of those sub-pixel samples. In addition, the same full/integer and half-pixel samples that can be used to obtain a quarter-pixel sample can also be used to obtain a one-eighth-pixel sample that the quarter-pixel sample is connected to. Hence, for every quarter-pixel sample, a motion vector could point to two additional positions/locations with one-eighth-pixel accuracy, where the two additional positions/locations can be calculated using the same half or integer-pixel samples which were used to obtain the quarter-pixel sample. Therefore, an arbitrary motion vector accuracy can be achieved without the need to perform additional interpolation stages or increase the complexity of a decoder configured to decode motion vector data. | 10-16-2008 |
20080260270 | SPATIALLY ENHANCED TRANSFORM CODING - A system and method for improving prediction error coding performance of various video compression algorithms. Various embodiments combine the energy compaction features of transform coding with localization properties of spatial coding. In various embodiments, the effects of pixel “outliers” are removed from the transform and are coded separately as a spatially coded pixel prediction, thereby improving the coding gain of the transform. | 10-23-2008 |
20090016626 | JOINT CODING OF MULTIPLE TRANSFORM BLOCKS WITH REDUCED NUMBER OF COEFFICIENTS - A system and method for video/image encoding and decoding, where transform coefficients associated with a plurality of blocks are reorganized and coded together. Various embodiments perform transform and quantization and generate transform coefficients, where the coefficients of the transform blocks are reorganized and interleaved. Additionally, an encoding process involves coding only a subset of the transform coefficients belonging to the transform blocks resulting in one or more transform blocks less than the original number of transform blocks, and putting this into a bitstream. A decoding process involves decoding the one or more resulting transform blocks including the subset of transform coefficients from the bistream, the transform coefficients being put in an array and decoded. The decoder de-interleaves the decoded transform coefficients and any remaining coefficients of the one or more transform blocks are filled in according to a plurality of different methods. After the one or more transform blocks are fully decoded, inverse transform and inverse quantization are performed and residual data is generated. | 01-15-2009 |
20090052535 | SYSTEM AND METHOD FOR PROVIDING IMPROVED INTRA-PREDICTION IN VIDEO CODING - A system and method for improving the efficiency of decoding intra-coded blocks in video decoding, even in the event that neighboring pixels of the block are unavailable. According to various embodiments, in addition to information that is used to describe how a prediction is formed using a specified process, other “side” information is also transmitted for use in the decoding process. For example, after the intra-prediction direction of a block is decoded, it is determined whether the intra-prediction requires pixels that are unavailable for the block. If such pixels are needed, than side information may be parsed from the bitstream in a predetermined manner. The prediction signal may then be reconstructed for the block using various pieces of information. | 02-26-2009 |
20090097545 | Fixed-Point Implementation of an Adaptive Image Filter with High Coding Efficiency - In accordance with an embodiment of the present invention, a method comprising: representing coefficients of an adaptive image filter in binary words wherein the coefficients are restricted and the binary words have a maximum number of bits defined at least in part by a precision index; computing at least one of a convolution sum and multiple partial convolution sums of the adaptive image filter wherein the at least one of a convolution sum and multiple partial convolution sums having a constrained value range and having a binary representation with a fixed maximum number of bits; and generating the output of the adaptive image filter based at least in part on the at least one of a convolution sum and multiple partial convolution sums, is disclosed. | 04-16-2009 |
20090097547 | Fixed-Point Implementation of an Adaptive Image Filter with High Coding Efficiency - In accordance with an embodiment of the present invention, a method comprising: representing coefficients of an adaptive image filter in binary words wherein the coefficients are restricted and the binary words have a maximum number of bits defined at least in part by a precision index; computing at least one of a convolution sum and multiple partial convolution sums of the adaptive image filter wherein the at least one of a convolution sum and multiple partial convolution sums having a constrained value range and having a binary representation with a fixed maximum number of bits; and generating the output of the adaptive image filter based at least in part on the at least one of a convolution sum and multiple partial convolution sums, is disclosed. | 04-16-2009 |
20090304084 | COMBINED MOTION VECTOR AND REFERENCE INDEX PREDICTION FOR VIDEO CODING - A system and method for improving the coding efficiency of motion vector information in video coding. According to various embodiments, a list of motion vector predictor candidates is arranged according to predefined rules. Each motion vector also has a reference index associated with it. One of the motion vector candidates is then selected as a predictor based on predefined rules, or the selection is explicitly signaled in the bitstream. The reference index associated with the selected motion vector is used as a reference index for the current block. The reference index is predicted along with the motion vector. Such embodiments can improve the compression efficiency of modern video codecs. | 12-10-2009 |
20100150226 | SWITCHING BETWEEN DCT COEFFICIENT CODING MODES - A system and method is provided for improving efficiency when entropy coding a block of quantized transform coefficients in video coding. Quantized coefficients are coded in two separate coding modes, namely, a run mode to a level mode coding mode. “Rules” for switching between these two modes are provided, and various embodiments are realized by allowing an entropy coder to adaptively decide when to switch between the two coding modes based on context information, the rules and/or by explicitly signaling the position of switching (e.g., whether or not it should switch coding modes). | 06-17-2010 |
20100246692 | FLEXIBLE INTERPOLATION FILTER STRUCTURES FOR VIDEO CODING - Systems and methods of signaling different filter structures for each pixel or sub-pixel position in motion compensation prediction video coding are provided. An encoder signals to a decoder one filter structure among a plurality of pre-defined candidates that is used for a respective pixel or sub-pixel position. In accordance with one embodiment, filter structures signaled to the decoder from the encoder “switch” between directional filter and radial filter structures during interpolation at the sub-pixel level. In accordance with another embodiment, filter structures that are signaled may switch between a directional filter structure and a separable filter structure at the sub-pixel level. Thus, not only can an encoder switch between different filter structures during interpolation, but a filter structure pair is provided that the encoder can utilize to interpolate a wide range of signals without increasing tap-length. | 09-30-2010 |
20100296587 | VIDEO CODING WITH PIXEL-ALIGNED DIRECTIONAL ADAPTIVE INTERPOLATION FILTERS - A system and method for implementing an adaptive interpolation filter structure that achieves high coding efficiency with significantly less complexity than more conventional systems. In various embodiments, a set-of integer pixels are defined that are used in the interpolation process to obtain each sub-pixel sample at different locations. Samples at each sub-pixel positions are generated with independent pixel-aligned one-dimensional (1D) adaptive interpolation filters. The filter coefficients are be transmitted to a decoder or stored into a bit stream. At the decoder end, the received filtered coefficients may be used in an interpolation process to create a motion-compensated prediction. | 11-25-2010 |
20110170609 | Apparatus, a method and a computer program for video processing - There is disclosed apparatuses, methods and computer program products for coding and decoding and specifically but not only for coding and decoding of image and video signals. It is determined whether two adjacent blocks of pixels of an image have a flat nature. The result of the determining is used to select a filter among at least a first filter and a second filter for filtering a block boundary between two adjacent blocks of pixels. The second filter is selected when said determining indicates that there are two adjacent blocks of pixels having a flat nature. At least a first reference value and a second reference value are selected for the second filter and used in filtering the block boundary. | 07-14-2011 |
20120121013 | Apparatus, A Method and a Computer Program for Video Coding - There is disclosed an apparatus, a method and a computer program for video coding. The apparatus comprises a selector configured for selecting an encoding method from a set of encoding methods comprising at least a first encoding method and a second encoding method for encoding a block of pixels of an image. The selector is further configured for selecting at least one control point among the pixels of said block of pixels; and selecting a first reference point different from said control point. The apparatus further comprises a determinator configured for determining values of the other pixels of said selected block of pixels on the basis of the value of said control point and the value of said at least one reference point. | 05-17-2012 |
20120128074 | VIDEO CODING USING SPATIALLY VARYING TRANSFORM - Transform coding is not restricted inside normal block boundary but is adjusted to the characteristics of the prediction error. Thereby it is possible to achieve a coding efficiency improvement by selecting and coding the best portion of the prediction error in terms of rate distortion tradeoff. | 05-24-2012 |
20120189057 | Motion Prediction in Video Coding - There is disclosed apparatuses, methods and computer programs for utilizing motion prediction in video coding. Coding type of a block of pixels of a video representation encoded in a bitstream is read, where values of said pixels having a first precision. If the type of the block is a block predicted by using two or more reference blocks, a first reference pixel location in a first reference block is determined and a second reference pixel location in a second reference block is determined. The first reference pixel location is used to obtain a first prediction having a second precision, which is higher than the first precision. The second reference pixel location is used to obtain a second prediction, also having the second precision. The first prediction and the second prediction are combined to obtain a combined prediction having the first precision. | 07-26-2012 |
20120243606 | METHODS, APPARATUSES AND COMPUTER PROGRAMS FOR VIDEO CODING - There is disclosed apparatuses, methods and computer programs for video coding. One or more subsets of a set of operations is determined; an operation among the operations within said subset of operations is selected; and an indication on the subset and on the selected operation is provided at the encoding. The decoding comprises determining one or more subsets of a set of operations; receiving a subset indication indicative of a selected subset among said one or more subsets and for receiving an operation indication indicative of an operation selected among operations within said selected subset; and selecting an operation on the basis of said operation indication. | 09-27-2012 |
20120250763 | METHOD AND APPARATUS FOR PROVIDING COMPLEXITY BALANCED ENTROPY CODING - A method, apparatus and computer program product are provided to enable the provision of efficient processing in the area of video coding and decoding by employing complexity balanced entropy coding in order to provide a high level of capability with respect to video coding and decoding in a cost effective manner. A method includes categorizing a plurality of syntax elements of video content into first and second categories based on a frequency of occurrence of the syntax elements in the video content. The method also entropy codes symbols that correspond to the first category of syntax elements and that have been subjected to a context update. Further, the method entropy codes symbols that correspond to the second category of syntax elements and that have bypassed context updating. A corresponding apparatus and computer program product are also provided. | 10-04-2012 |
20120294357 | Methods, Apparatuses and Computer Programs for Video Coding - There is disclosed apparatuses, methods and computer programs for video coding. The filtering process to be applied to intra predicted sample values is selected and adapted based on the characteristics of the sample prediction process. According to some embodiments an angularity information and pixel values for filtering by a filter are received. The angularity information is used to adapt the filter. The adapting may comprise selecting a filter algorithm and/or filter coefficients. The selected pixels are then filtered by the adapted filter. | 11-22-2012 |
20130094776 | METHOD FOR CODING AND AN APPARATUS - The disclosure relates to encoding and decoding image information. The encoding comprises receiving a block of pixels; determining a set of potential reference samples for the block of pixels; selecting a subset of the set of potential reference samples to be used as reference samples for the block of pixels; and using the selected reference samples to determine a DC prediction value for the block of pixels. A prediction error is determined for a pixel in the block of pixels on the basis of the DC prediction value. The decoding comprises receiving an encoded block of pixels; determining reference samples for the encoded block of pixels; and using the determined reference samples to define a DC prediction value for the block of pixels. A prediction error is received for a pixel of the encoded block of pixels. The pixel value is reconstructed on the basis of the DC prediction value. | 04-18-2013 |
20130114723 | METHOD FOR CODING AND AN APPARATUS - The invention relates to a method for encoding, a method for decoding, an apparatus, computer program products, an encoder and a decoder for video information. The motion vector for a block in a video image is predicted from a set of motion vector prediction candidates determined based on previously-coded motion vectors. A motion vector prediction candidate is included in the set based on the location of the block associated with the first spatial motion vector prediction candidate and in comparison with motion vector prediction candidates already in the set. | 05-09-2013 |
20130202052 | METHOD FOR CODING AND AN APPARATUS - There is disclosed a method comprising receiving a set of coefficients; and determining whether a sign of a coefficient in the set of coefficients can be embedded in a bitstream. If the determining indicates that the sign of the coefficient in the set of coefficients can be embedded in the bitstream, an indication of the embedded sign is inserted into the bitstream. There is also disclosed a method comprising receiving a set of decoded coefficients; and determining whether a bitstream contains an indication of an embedded sign of a coefficient. If the determining indicates that the bitstream contains the indication of an embedded sign of a coefficient, the sign is determined on the basis of the decoded coefficients; and the sign of the coefficient is modified on the basis of the determined sign. | 08-08-2013 |
20140003504 | Apparatus, a Method and a Computer Program for Video Coding and Decoding | 01-02-2014 |
20140003505 | METHOD AND APPARATUS FOR VIDEO CODING | 01-02-2014 |
20140085415 | METHOD AND APPARATUS FOR VIDEO CODING - There are disclosed various methods, apparatuses and computer program products for video encoding and decoding. In some embodiments the method for encoding comprises obtaining samples of a video signal for encoding a first layer representation of the video signal and a second layer representation of the video signal. An encoded first layer representation of the video signal is used as a prediction reference in the encoding of the second layer representation of the video signal. It is evaluated whether to use filtering in the encoding of the second layer representation. If the evaluation indicates to use filtering in the encoding of the second layer representation, the method further comprises filtering the encoded first layer representation; and using the filtered encoded first layer representation as the prediction reference in the encoding of the second layer representation of the video signal. | 03-27-2014 |
20140092977 | Apparatus, a Method and a Computer Program for Video Coding and Decoding - In some embodiments, there is provided an apparatus, a computer readable storage medium stored with code thereon for use by an apparatus, and a video decoder, for decoding a video bitstream, to derive a motion compensated prediction for an enhancement layer block based on a motion compensation process on the co-located base layer block using the same or similar motion vector of enhancement layer blocks and base layer reference pictures. In other embodiments, there is provided a method, an apparatus, a computer readable storage medium stored with code thereon for use by an apparatus, and a video encoder, for encoding a video bitstream, to derive a motion compensated prediction for an enhancement layer block based on a motion compensation process on the co-located base layer block using the same or similar motion vector of enhancement layer blocks and base layer reference pictures. | 04-03-2014 |
20140133567 | APPARATUS, A METHOD AND A COMPUTER PROGRAM FOR VIDEO CODING AND DECODING - There is disclosed a method, apparatus and computer program product in which a set of valid motion vector values for encoding and decoding may depend on the reference picture used. A current block of a frame is selected for encoding, and a reference block for the current block is selected. On the basis of the selected reference block a reference type is determined. On the basis of the reference type and the reference block a motion vector for the current block is determined. Motion vector information is encoded and decoded on the basis of the determined motion vector. | 05-15-2014 |
20140218473 | METHOD AND APPARATUS FOR VIDEO CODING AND DECODING - There are disclosed various methods, apparatuses and computer program products for video encoding and decoding. In some embodiments diagonal inter-layer prediction is enabled by providing an indication of a reference picture. In some embodiments the indication is provided as a combination of a temporal picture identifier and a layer identifier of the reference picture in another layer than the picture to be predicted. In an encoding method a first picture of a first layer representing a first time instant is encoded; a second picture representing a second time instant on a second layer is predicted by using the first picture as a reference picture; and | 08-07-2014 |
20140219346 | METHOD AND APPARATUS FOR VIDEO CODING AND DECODING - Various methods, apparatuses and computer program products for video encoding and decoding. In some embodiments a first picture having a first resolution on a first layer is encoded without inter-layer prediction; a second picture having a second resolution on a second layer is encoded without inter-layer prediction; a third picture having the second resolution on the second layer is encoded without inter-layer prediction and without temporally referencing to pictures prior to the second picture. Further, a corresponding indication is encoded. In some embodiments one or more indications are received to determine if a switching point, referring to a picture coded using inter-layer prediction, from the first layer to the second layer exists, and if so, pictures in the first layer prior to the switching point; pictures associated with the switching point; and pictures in the second layer after the switching point may be decoded. | 08-07-2014 |
20140254681 | APPARATUS, A METHOD AND A COMPUTER PROGRAM FOR VIDEO CODING AND DECODING - There are disclosed various methods, apparatuses and computer program products for video coding. In some embodiments motion parameters are obtained for a block of first layer samples and a first layer reference picture for the block of first layer samples is identified. A second layer reference picture corresponding to the first layer reference picture is identified, intermediate reference picture samples are derived by using sample values of the first layer reference picture and information based on sample values of the second layer reference picture, and inter-layer reference picture samples are derived by using intermediate reference picture samples and first layer samples. In some embodiments motion compensated sample values are derived from the second layer reference picture on the basis of the motion parameters; and an inter-layer reference block is derived by using residual sample values of first layer samples and motion compensated sample values from the second layer reference picture. | 09-11-2014 |
20140314148 | APPARATUS, A METHOD AND A COMPUTER PROGRAM FOR VIDEO CODING AND DECODING - A method and related apparatus for decoding an image sequence from a bitstream, wherein an identifier indicating if all output pictures are decodable with a predefined set of reference pictures is decoded; an indication of required reference pictures for a given output picture is decoded; the indicated at least one reference picture for the given output picture is decoded; and the at least one output picture is decoded. | 10-23-2014 |
20140321560 | METHOD AND TECHNICAL EQUIPMENT FOR VIDEO ENCODING AND DECODING - An encoding and decoding method and technical equipment for the same. The method comprises encoding a picture at various resolutions; determining the position information of samples of each resolution; using the said determined position information during upsampling process of low resolution picture to a higher resolution; and signalling the determined position information of the samples. | 10-30-2014 |