Abstract: A method of encoding a video sequence comprising Reference Picture Sets (RPSs) is provided. The method comprises arranging the RPSs in transmission order in a data structure, such as a Sequence Parameter Set (SPS), determining whether explicit RPS transmission is used for an RPS of a current picture of the video sequence, and encoding information indicating an RPS comprised in the data structure to be used for predicting the RPS of the current picture, such as delta_idx_minus1, only if explicit RPS transmission is used. By transmitting delta_idx_minus1 only if explicit RPS transmission is used, and interpreting delta_idx_minus1 to be equal to zero otherwise, a reduced bitrate is achieved. Further, a method of decoding a video sequence comprising RPSs, corresponding computer programs and computer program products, as well as corresponding encoders and decoders are provided.

Abstract: The embodiments of the present invention relate to compression of parameters of an encoded texture block such that an efficient encoding is achieved. Index data is used as an example of parameters to be encoded. Accordingly, encoding the index data is achieved by predicting the index data, wherein the prediction is done in the pixel color domain, where changes often are smooth, instead of in the pixel index domain where the changes vary a lot. Hence, according to embodiments of the present invention the index data is predicted from previously predicted neighboring pixels taking into account that the base value and a modifier table value are known. When the index value is predicted the real index value can be decoded with the prediction as an aid. Since this way of predicting the index provides a very good prediction, it lowers the number of bits needed to represent the pixel index.

Abstract: A decoding system comprises N different decoders each having a unique circuitry that is different from the circuitries of the other N?1 decoders. The decoders each generate at least one texel value based on an input encoded texel block. A value selector is configured to selectively output at least N texel values from at least one of the decoders based on the position of the at least N texels relative a boundary of a texel block comprising at least one of the at least N texels. A pixel calculator calculates a pixel value of a decoded pixel based on the at least N selected texel values from the value selector.

Abstract: First and second codewords are determined, based on first feature vector components of the image elements in an image block, as representations of a first and second component value. Third and fourth codewords are determined, based on second vector components, as representations of a third and fourth component value. First N1 and second N2 resolution numbers are selected based on the relation of a distribution of the first vector components and a distribution of the second vector components. N1 additional component values are generated based on the first and second component values and N2 additional component values are generated based on the third and fourth component values. Component indices indicative of the generated component values are then provided for the different image elements.

Abstract: The embodiments of the present invention reduce the compression time in order to achieve a faster texture compression. That is achieved by guessing, i.e. estimating the best table or tables (e.g. from tables 0 to 7) representing luminance information, and to only execute the compression for the table(s) estimated to provide the best luminance information.

Abstract: The embodiments of the present invention relates to a method and processor for texture compression, wherein an image block is divided into two halfblocks, which are either lying, referred to as flipped configuration or standing referred to as the non-flipped configuration. It is estimated whether the flipped or the non-flipped configuration provides the best result for compressing a block and by only executing the compression for the configuration that is estimated to give the best result for said block.

Abstract: A compressed pixel block (400) is decompressed by defining multiple available property values. At least one reference point relative the pixel block (300) is identified based on a reference codeword (410) of the compressed pixel block (400). Pixel indices of the pixels (310) are determined based on the respective positions of pixels (310) in the pixel block (300) relative the at least one reference point. These pixel indices are used for selecting among the multiple defined property values. The selected property values are then assigned to pixels (310) to be decompressed based on their determined pixel indices.

Abstract: A method of retrieving information comprised in a barcode is disclosed. The method comprises detecting that the barcode is present in a first image having a first image quality and capturing a first region, acquiring, when it is detected that the barcode is present, a second image having a second image quality and capturing a second region, wherein the second image quality is higher than the first image quality, and wherein the second region at least partly overlaps the first region, and decoding the barcode based on the second image to retrieve the information.

Abstract: An image (1) is decomposed into multiple superblocks (20, 22), each encompassing multiple pixel blocks (30A-30D, 32A-32D) having multiple pixels (40). The property values of a superblock (20) is fixed rate compressed to get a compressed block having a target bit length. The compressed block is stored in the memory locations (310, 320) assigned to the multiple pixel blocks (30A-30D) encompassed by the superblock (20) to thereby get multiple copies of the compressed block in the memory (300). The multiple copies collectively constitute a compressed representation of the superblock (20). When accessing a compressed block in a memory location (310) using random access during decoding, property values for neighboring pixel blocks (30B-30D) are obtained for free without the need for any further memory access.

Abstract: A block of image elements is compressed by determining a parameter representative of a size of a bounding section in vector space encompassing feature vectors associated with the image elements. This size parameter is used to provide a deterministic, pseudo-random pattern of multiple representation vectors encompassed by the bounding section. A vector among multiple representation vectors is selected as representation of the feature vector of an image element. An identifier associated with selected vector is assigned to the image element and included in the compressed block which also comprises representations of the size parameter.

Abstract: A tile of pixels is encoded by variable length encoding at least a first block of pixels into a first sequence of symbols and a second block of pixels into a second sequence of symbols. The symbols of the first and second sequences are co-organized into a combined sequence of symbols in which the symbols of the first sequence are readable in a first reading direction and at least a portion of the symbols in the second sequence are readable in a second, opposite reading direction. The encoding of the tile to form one or more combined sequences significantly reduces the bandwidth requirements when writing the tile to a pixel value buffer. The co-organization of the first and second sequences enables parallel reading and decoding of the first and second sequences from the pixel value buffer, thereby reducing any decoding latency.

Abstract: Multi-mode decoding and encoding of texture blocks are disclosed wherein in a default decoding and encoding mode all bits of a codeword sequence are available as payload bits for representing texel values of the texels in the texture block. In an auxiliary encoding and decoding mode one less bit of the codeword sequence is available as payload bits. The auxiliary mode is employed as a complement to the default mode and will be used to process those texture blocks, which the default mode handles poorly.

Abstract: First and second codewords are determined, based on first feature vector components of the image elements in an image block, as representations of a first and second component value. Third and fourth codewords are determined, based on second vector components, as representations of a third and fourth component value. First N1 and second N2 resolution numbers are selected based on the relation of a distribution of the first vector components and a distribution of the second vector components. N1 additional component values are generated based on the first and second component values and N2 additional component values are generated based on the third and fourth component values. Component indices indicative of the generated component values are then provided for the different image elements.

Abstract: The invention relates to compression of a pixel block (300) of depth values. A reference codeword (410) is determined as a representation of a reference depth value. A row (420) and a column (430) slope codeword are determined as representations of a basic depth slope for the rows (310) and columns (320) in the block (300), respectively. Representations indicating pixel positions where a slope change occurs along at least a portion of a row (310) or column (320) is determined for at least a subset of the rows (310) or columns (320). A mode codeword (440) is determined as a representation of a set of multiple slope correction patterns. A respect pattern codeword (450) is then selected for rows (310) or columns (320) as identifier of one of the slope correction patterns.

Abstract: A method of retrieving information comprised in a barcode is disclosed. The method comprises detecting that the barcode is present in a first image having a first image quality and capturing a first region, acquiring, when it is detected that the barcode is present, a second image having a second image quality and capturing a second region, wherein the second image quality is higher than the first image quality, and wherein the second region at least partly overlaps the first region, and decoding the barcode based on the second image to retrieve the information. A corresponding program product and a corresponding arrangement are also disclosed along with a communication device comprising the arrangement.

Abstract: Multi-mode decoding and encoding of texture blocks are disclosed wherein in a default decoding and encoding mode all bits of a codeword sequence are available as payload bits for representing texel values of the texels in the texture block. In an auxiliary encoding and decoding mode one less bit of the codeword sequence is available as payload bits. The auxiliary mode is employed as a complement to the default mode and will be used to process those texture blocks, which the default mode handles poorly.

Abstract: A face data acquirer includes an image capture module arranged to capture an image from a video stream of a video conference. A face detection module is arranged to determine a subset of the image, the subset representing a face. An identity acquisition module is arranged to acquire an identity of a video conference participant coupled to the face represented by the subset of the image. A face extraction module is arranged to extract face data from the subset of the image and to determine whether to store the extracted face data for subsequent face recognition. A corresponding end user video conference device, server, method, computer program and computer program product are also provided.

Abstract: A method for updating values of a depth buffer comprising values for display blocks of a display, and a device for implementing the method. The display is partitioned into a plurality of display regions, including a plurality of display blocks and having a minimum region depth value and a maximum region depth value. Each display region includes a plurality of display subregions. A minimum subregion depth value and a maximum subregion depth value are determined relative to at least one of the minimum region depth value and the maximum region depth value.

Abstract: A first and a second data value are co-compressed by generating a sequence of symbols having a most significant symbol that is the most significant symbol of a compressed representation of the first data value and a least significant symbol that is the most significant symbol of a compressed representation of the second data value. The compressed representation of the first data value corresponds to at least a portion of the symbols of the sequence of symbols starting from the most significant symbol and extending towards the least significant symbol in a first reading direction. The compressed representation of the second data value also corresponds to at least a portion of the symbols of the sequence of symbols, however, starting from the least significant symbol and extending in an opposite reading direction towards the most significant symbol.

Abstract: In an image-encoding scheme, an input image is decomposed into several image blocks (600) comprising multiple image elements (610). The image blocks (600) are encoded into encoded block representations (700). In this encoding, color weights are assigned to the image elements (610) in the block (600) based on their relative positions in the block (600). At least two color codeword (710, 720, 730, 740) are determined, at least partly based on the color weights. These codewords (710, 720, 730, 740) are representations of at least two color values. The original colors of the image elements (610) are represented by color representations derivable from combinations of the at least two color values weighted by the assigned color weights.