Abstract: A picture (1) with multiple slices (2-5) is encoded by generating a coded slice representation for each of the slices. A slice flag is set to a first value for the first slice (2) in the picture (1) and corresponding slice flags of the remaining slices (3-5) are set to a second defined value. A respective slice address is generated for each remaining slice (3-5) to enable identification of the slice start position within the picture (1) for the slice. A coded picture representation (50) of the picture (1) comprises the coded slice representations, the slice addresses and the slice flags. The slice flags enable differentiation between slices (3-5) for which slice addresses are required and the slice (2) per picture (1) for which no slice address is needed to identify its slice start position.

Abstract: An image processing method involves determining a global motion between a reference frame and a current frame in a frame sequence. A reference block is identified in the reference frame for a current block based on the global motion. A classification parameter is calculated based on the pixel values of the current block and the reference block. The parameter can be used for classifying the block as belonging to the background or foreground of the current frame. The parameter is preferably also utilized in frame rate-up conversion when extrapolating or interpolating new frames.

Abstract: A stream (1) of media frames (12-16, 22-26, 32-36) is generated by providing multiple media frames (22-26) having respective assigned default timestamps (40) defining rendering times of the media data of the media frames (22-26) according to a default rendering time schedule. Respective alternative timestamps (50) are assigned to at least a portion of the media frames (22-26). These alternative timestamps (50) define alternative rendering times of the media data of the media frames (22-26) according to an alternative rendering time schedule. The alternative timestamps (50) can be used for providing an efficient media rendering when tuning in to the stream (1) at an intermediate position of a frame grouping (20) of the media frames (22-26) thereby missing some of the media frames (22, 24) of the frame grouping (20).

Abstract: Co-processing of a video frame (32) and its associated depth map (34) suitable for free viewpoint television involves detecting respective edges (70, 71, 80, 81) in the video frame (32) and the depth map (34). The edges (70, 71, 80, 81) are aligned and used to identify any pixels (90-92) in the depth map (34) or the video frame (32) having incorrect depth values or color values based on the positions of the pixels in the depth map (34)or the video frame (32) relative an edge (80) in 5 the depth map (34) and a corresponding, aligned edge (70) in the video frame (32). The depth values or color values of the identified pixels (90-92) can then be corrected in order to improve the accuracy of the depth map (32) or video frame (34).

Abstract: Metadata defining decoding and rendering instructions for media content to be co-rendered in a media presentation is divided and distributed as track fragments provided in different media container files. Track fragment adjustment information is included in at least one such track fragment in order to define rendering timing relationships between media content portions defined by the track fragments in a current media container file. The rendering timing relationships enable a correct time alignment of the playback of the media content to be co-rendered to achieve a synchronized media presentation. The track fragment adjustment information is particularly advantageous in connection with tuning in or a random access in a stream of media container files comprising fragmented metadata.

Abstract: A media container file (1) is generated by organizing media data (2; 3) defined by a media track (12) in the file (1). Sub-track information (72, 74) identifying media data portions (4, 5; 6, 7, 8) of the media data (2; 3) is organized for each sub-track of multiple sub-tracks defined in the media track (12). At least one of the sub-tracks is assigned selection information (62, 64) defining a selective processing of the media data portion (4, 5; 6, 7, 8) defined by the sub-track in relation to other media data organized in the media container file (1). The media data (2, 3) advantageously relate to layered media or media defining multiple camera views which are organized into sub-tracks (12). The selection information (62, 64) allows selection among tracks (12) and sub-tracks when setting up a media session and switching between tracks (12) and sub-tracks during such a media session.

Abstract: A method of encoding a plurality of adaptive filter coefficients (104, 107, 112) into a bitstream (110). The method comprises the steps of entropy encoding (109) the adaptive filter coefficients (104, 107, 112) into the bitstream (110), whereby a prediction (202) for an instance (204) of the adaptive filter coefficients is determined (201) based on at least one of the remaining adaptive filter coefficients (206), a prediction error (205) is determined (203) based on the difference between the instance (204) of the adaptive filter coefficients and the prediction (202), and wherein the step of entropy encoding (109) the plurality of adaptive filter coefficients (104, 107, 112) comprises entropy encoding (109) the prediction error (205) for the instance (204) of the adaptive filter coefficients and entropy encoding (109) the remaining adaptive filter coefficients (206).

Abstract: In video encoding and decoding predictions may be generated by intra-frame prediction. Intra-frame prediction uses reconstructed pixels in a reconstructed frame. Intra-frame prediction is performed by extending the reconstructed pixels into a predicted block using intra-frame prediction modes, each intra-frame prediction mode indicating a direction of the extension. In order to reduce the number of possible intra-frame prediction modes, a subset is selected from a predetermined set of possible intra-frame prediction modes. A subset of intra-frame prediction modes can be created by forming preselection sets of intra-frame prediction modes on the basis of similarity of their associated predicted blocks and selecting a representative intra-frame prediction mode from each preselection set.

Abstract: Metadata defining decoding and rendering instructions for media content to be co-rendered in a media presentation is divided and distributed as track fragments (15, 16) provided in different media container files (11). Track fragment adjustment information (20) is included in at least one such track fragment (15) in order to define rendering timing relationships between media content portions defined by the track fragments (15, 16) in a current media container file (11). The rendering timing relationships enable a correct time alignment of the playback of the media content to be co-rendered to achieve a synchronized media presentation. The track fragment adjustment information (20) is particularly advantageous in connection with tuning in or a random access in a stream of media container files (1, 11) comprising fragmented metadata.

Abstract: A media stream comprising rich media scene packets and scene update packets is complemented with a data packet defining an exit point for interrupting rendering rich media of the stream and a scene update packet associated with the data packet and defining an entry point back to rendering rich media of the stream. The exit-entry point pair defines an alternative media rendering route that can be used by user terminals to recover from errors in the media stream.

Abstract: A method and device for determining an adaptive filter having multiple filter parameters, wherein a first filter parameter has a first level of adaptivity and a second filter parameter has a second, different level of adaptivity. Parameter values for the first filter parameter are determined among a first set of allowable filter parameter values. Parameter values for the second filter parameter are correspondingly determined among a second, different set of allowable filter parameter values. The different levels of adaptivity in the filter parameters are achieved because the second set includes more allowable filter parameter values than the first set. The adaptive filter is advantageously used in filtering in intra- or inter-predication during video encoding and decoding.

Abstract: A solution according to one or more embodiments of the present invention is to reconstruct image blocks where only the frequency coefficient that is most sensitive to changes of an average value of the residual image block, typically the lowest frequency coefficient, is present with a flat residual image. The other image blocks are reconstructed by applying an inverse spatial 2D transform. Hence, the other image blocks comprise image blocks with multiple coefficients and image blocks with a single coefficient and wherein the single coefficient is not the coefficient determining that is most sensitive to changes of an average value of the residual image block.

Abstract: A border region is identified in an image by calculating an average of pixel values in a row or column of the image. Differences in property values are determined between each pixel in the row or column and a neighboring pixel present on a same column or row but in a neighboring row or column. An average difference is calculated based on these differences. The pixels in the row or column are classified as belonging to a border region or internal region of the image based on the average pixel value and the average pixel difference.

Abstract: A technique for encoding and decoding data pertaining to multiple video views is presented. A method embodiment of the encoding technique comprises the steps of providing first picture stream belonging to a first view and performing a first encoding operation to encode a picture of the first picture stream. The first encoding operation is based on a single-view video codec and provides encoder state information relevant for the encoding of another picture of the first picture stream. Also provided is a second picture stream belonging to a second video view. A second encoding operation is performed to encode a picture of the second picture stream based on the single-view video codec, wherein the second encoding operation is based on the encoder state information provided by the first encoding operation. On the basis of the encoded picture of the first picture stream and encoded picture of the second picture stream, dedicated video streams are generated.

Abstract: An adaptive filter to use in connection with prediction-based pixel block encoding and decoding is determined independently at the encoder and decoder side through a template-based procedure. A pixel block (12) has an identified reference pixel block (22) in a reference frame (20). A template (16) of multiple pixels (18) adjacent the pixel block (12) and a reference template (26) of multiple pixels (28) adjacent the reference pixel block (22) are used for determining the filter parameters of the adaptive filter. The determined adaptive filter is then applied to the reference pixel block (22) and is used for generating an encoded representation (40) of the pixel block (12) during encoding and or generating a decoded representation of the pixel block (12) during decoding.

Abstract: A block-specific filter decision value is calculated for a pixel block (10) in a video frame. If the block-specific filter decision value is below a block-specific threshold, each row or column (12) in the block (10) is individually processed in order to select between a strong and a weak de-blocking filter. A respective line-specific filter decision value is thereby calculated for each row or column (12) in the block (10) and compared to a line-specific threshold. If the line-specific filter decision value calculated for a row or column (12) is below the line-specific threshold a strong de-blocking filter is selected for the row or column (12), otherwise a weak de-blocking filter is instead selected to combat any blocking artifacts.

Abstract: A picture (1) with multiple slices (2-5) is encoded by generating a coded slice representation for each of the slices. A slice flag is set to a first value for the first slice (2) in the picture (1) and corresponding slice flags of the remaining slices (3-5) are set to a second defined value. A respective slice address is generated for each remaining slice (3-5) to enable identification of the slice start position within the picture (1) for the slice. A coded picture representation (50) of the picture (1) comprises the coded slice representations, the slice addresses and the slice flags. The slice flags enable differentiation between slices (3-5) for which slice addresses are required and the slice (2) per picture (1) for which no slice address is needed to identify its slice start position.

Abstract: In a method for media session management a user terminal upon detecting S0, S00 switching to a media stream on a channel from a unicast transport source, requesting S1 transmission of the media stream by indicating a predetermined starting frame for the transmission and a media server transmitting S2 the requested media frame starting with a media frame as indicated in the request.

Abstract: In a method of enabling representation switching during HTTP streaming sessions in a communication system, arranging (S10) available representations into groups, providing (S20) information identifying the groups and their respective representations, and switching (S30) representation based on the provided group identify information.

Abstract: A method of controlling adaptive HTTP streaming of media content between a HTTP server and a HTTP client in a communication system, in which system media content is arranged as a plurality of periods, and each such period comprises a plurality of representations of media segments, which method includes the steps of providing (S10) temporal alignment information for the media segments of the plurality of representations, which temporal alignment information provides indications about a temporal relation between the segments of the plurality of representations of the media content. Further, the method includes providing (S20) key frame location information for the media segments, which key frame location information provides indications about locations of key frames in the media segments of the plurality of representations.