Abstract: 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.

Abstract: 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.

Abstract: A method of interpolation in video coding in which an image comprising pixels arranged in rows and columns and represented by values having a specified dynamic range, the pixels in the rows residing at unit horizontal locations and the pixels in the columns residing at unit vertical locations, is interpolated to generate values for sub-pixels at fractional horizontal and vertical locations, the method comprising: a) when values for sub-pixels at half unit horizontal and unit vertical locations, and unit horizontal and half unit vertical locations are required, interpolating such values directly using weighted sums of pixels residing at unit horizontal and unit vertical locations; b) when values for sub-pixels at half unit horizontal and half unit vertical locations are required, interpolating such values directly using a weighted sum of values for sub-pixels residing at half unit horizontal and unit vertical locations calculated according to step (a); and c) when values for sub-pixels at quarter unit horizon

Abstract: An approximation of a DCT and a quantization are to be applied subsequently to digital data for compression of this digital data. In order to improve the transform, a predetermined transform matrix is simplified to require less operations when applied to digital data. In addition, elements of the simplified transform matrix constituting irrational numbers are approximated by rational numbers. These measures are compensated by extending a predetermined quantization to include the operations which were removed in the simplification of the predetermined transform matrix. The included operations are further adjusted to compensate for the approximation of elements of the simplified transform matrix by rational numbers. If the simplified transform matrix and the extended quantization are used as basis for implementation, a fast transform with a good resulting quality can be achieved. An approximation of an IDCT employed in decompression of compressed digital data can be simplified correspondingly.

Abstract: 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.

Abstract: An apparatus for providing motion estimation for video encoding includes a selection element and a processing element. The selection element is configured to select a subset including less than all of candidate pixel locations from among a plurality of candidate pixel locations used for motion vector determination based on a relationship between a best candidate pixel location of a first level of accuracy and a best candidate pixel location of a second level of accuracy. The processing element is configured to process an input video sequence to determine a motion vector at the first level of accuracy, to refine the motion vector at the second level of accuracy, and to determine the motion vector at a third level of accuracy using only the subset of candidate pixel locations.

Abstract: A method and system for coding a video sequence based on motion compensated prediction, wherein an interpolation filter is used to generate predicted pixel values for picture blocks in the video sequence. The interpolation filter for use in conjunction with a multi-picture type is shorter or having fewer coefficients than the interpolation filter for use in conjunction with a single-picture type. As such, the complexity of the interpolation filter for the multi-picture type can be reduced. Furthermore, the interpolation filter may be changed based on the characteristics of the block, the size and/or the shape of the block.

Abstract: A method of interpolation in video coding in which an image comprising pixels arranged in rows and columns and represented by values having a specified dynamic range, the pixels in the rows residing at unit horizontal locations and the pixels in the columns residing at unit vertical locations, is interpolated to generate values for sub-pixels at fractional horizontal and vertical locations, the method comprising: a) when values for sub-pixels at half unit horizontal and unit vertical locations, and unit horizontal and half unit vertical locations are required, interpolating such values directly using weighted sums of pixels residing at unit horizontal and unit vertical locations; b) when values for sub-pixels at half unit horizontal and half unit vertical locations are required, interpolating such values directly using a weighted sum of values for sub-pixels residing at half unit horizontal and unit vertical locations calculated according to step (a); and c) when values for sub-pixels at quarter unit horizont

Abstract: Methods, devices, and computer code products for encoding and decoding a video signal involving encoding blocks of the video signal by scan position within a coding cycle in decreasing order to increase the probability that the next symbol will be non-zero. Scalable video decoding techniques can include setting a state variable for a block to a run length if the state variable for the current block is zero otherwise decrementing the state variable if it is not zero. The current coefficient for the block can be set to the terminating value if the state variable is zero otherwise the coefficient can be set to zero if the state variable is not zero.

Abstract: The invention relates to an approximation of a DCT and a quantization which are to be applied subsequently to digital data for compression of this digital data. In order to improve the transform, it is proposed to simplify a predetermined transform matrix to require less operations when applied to digital data. In addition, elements of the simplified transform matrix constituting irrational numbers are approximated by rational numbers. These measures are compensated by extending a predetermined quantization to include the operations which were removed in the simplification of the predetermined transform matrix. The included operations are further adjusted to compensate for the approximation of elements of the simplified transform matrix by rational numbers. If the simplified transform matrix and the extended quantization are used as basis for implementation, a fast transform with a good resulting quality can be achieved.

Abstract: The invention relates to an approximation of a DCT and a quantization which are to be applied subsequently to digital data for compression of this digital data. In order to improve the transform, it is proposed to simplify a predetermined transform matrix to require less operations when applied to digital data. In addition, elements of the simplified transform matrix constituting irrational numbers are approximated by rational numbers. These measures are compensated by extending a predetermined quantization to include the operations which were removed in the simplification of the predetermined transform matrix. The included operations are further adjusted to compensate for the approximation of elements of the simplified transform matrix by rational numbers. If the simplified transform matrix and the extended quantization are used as basis for implementation, a fast transform with a good resulting quality can be achieved.

Abstract: A method of interpolation in video coding in which an image comprising pixels arranged in rows and columns and represented by values having a specified dynamic range, the pixels in the rows residing at unit horizontal locations and the pixels in the columns residing at unit vertical locations, is interpolated to generate values for sub-pixels at fractional horizontal and vertical locations, the method comprising: a) when values for sub-pixels at half unit horizontal and unit vertical locations, and unit horizontal and half unit vertical locations are required, interpolating such values directly using weighted sums of pixels residing at unit horizontal and unit vertical locations; b) when values for sub-pixels at half unit horizontal and half unit vertical locations are required, interpolating such values directly using a weighted sum of values for sub-pixels residing at half unit horizontal and unit vertical locations calculated according to step (a); and c) when values for sub-pixels at quarter unit horizont

Abstract: A method and system for coding a video sequence based on motion compensated prediction, wherein an interpolation filter is used to generate predicted pixel values for picture blocks in the video sequence. The interpolation filter for use in conjunction with a multi-picture type is shorter or having fewer coefficients than the interpolation filter for use in conjunction with a single-picture type. As such, the complexity of the interpolation filter for the multi-picture type can be reduced. Furthermore, the interpolation filter may be changed based on the characteristics of the block, the size and/or the shape of the block.

Abstract: The invention relates to an approximation of a DCT and a quantization which are to be applied subsequently to digital data for compression of this digital data. In order to improve the transform, it is proposed to simplify a predetermined transform matrix to require less operations when applied to digital data. In addition, elements of the simplified transform matrix constituting irrational numbers are approximated by rational numbers. These measures are compensated by extending a predetermined quantization to include the operations which were removed in the simplification of the predetermined transform matrix. The included operations are further adjusted to compensate for the approximation of elements of the simplified transform matrix by rational numbers. If the simplified transform matrix and the extended quantization are used as basis for implementation, a fast transform with a good resulting quality can be achieved.