Telefonaktiebolaget Lm Ericsson (publ)

Thomas Rusert

Kenneth Andersson

Rickard Sjöberg

Zhuangfei Wu

Jonatan Samuelsson

Markus Kampmann

Clinton Priddle

Daniel Catrein

Thorsten Lohmar

Andrey Norkin

Frank Hartung

Martin Pettersson

Jörg Huschke

Per Fröjdh

Björn Johansson

Ivana Girdzijauskas

Apostolos Georgakis

Jacob Ström

Per Wennersten

Torbjörn Einarsson

Richard Mitic

Jack Enhorn

Mai-Anh Phan

Ying Wang

Beatriz Grafulla-González

Christopher Hollmann

Julien Michot

Sanbao Xu

Richard Sjöberg

Pravin Kumar Rana

Markus H Flierl

Bjorn Stig Johansson

Zhuangfel Wu

The present invention relates to an encoder, transcoder and methods thereof. A transcoder embodiment involves transcoding a bitstream representing an original video source from an input video format to an output video format. An encoder embodiment involves providing transform coefficients in side information related to an encoded video bitstream.

Methods, encoder, and transcoder for transcoding

In one aspect, a compressed video bit stream is received and divided into packets that comprise either video data or supplemental information. Each packet is marked with a first subset identifier associated with a corresponding bit stream subset. A first sequence parameter set (SPS) is marked with the same first subset identifier as its associated bit stream subset. The first SPS comprises a second subset identifier indicating a decoding dependency of the bit stream subset associated with the first subset identifier on a bit stream subset associated with the second subset identifier. In another aspect, the packets from the bit stream are received and the first SPS is extracted. The first and second subset identifiers are used as relevant subset identifiers, and for each received packet, the first subset identifier is inspected and the packet is extracted when the first subset identifier matches one of the relevant subset identifiers.

Indicating bit stream subsets

According to one aspect the present invention relates to a method for a video encoder. The method comprises providing () to a transcoder a first bitstream representing a video sequence with a first format, creating () a second bitstream representing transcoding information indicative of a transcoding method that should be used by the transcoder for transcoding the video sequence from the first format to a second format, and providing () to the transcoder the second bitstream.

Methods and arrangements for transcoding

An example method includes receiving a video bitstream with a high fidelity input format and side information related to the video bitstream. The side information includes a video bitstream representing the original video source with a low fidelity input format, coding parameters optimized based on knowledge of the original video source, transform coefficients, indicative of a residual between the original video source and a decoded version of the high fidelity format. The method further includes decoding the side information to generate transcoding guiding information, estimating a representation of video bitstream with a low fidelity output format, based on the received bit stream and the generated transcoding guiding information, improving the estimated low-fidelity representation by adding the transform coefficients of the side information to transform coefficients generated from the estimated low-fidelity representation, and encoding the improved estimated representation of the low-fidelity bitstream.

Method and arrangement for transcoding a video bitstream

Multi-layer dependencies are signaled in an efficient way for a multi-view video stream (). Coding or decoding relationship information defining coding or decoding dependencies is represented in bit-efficient syntax code, preferably through usage of hierarchical layer dependencies using layer indices for representing layer dependencies.

Multi-layer video stream encoding and decoding

In a method of transcoding of a video bitstream by a transcoder arrangement, performing the steps of receiving (S) a video bitstream with a predetermined input video format, receiving (S) side information related to the video bitstream, the side information comprising at least one of mode or motion or in-loop filter information relating to at least one other predetermined video format for the video bitstream. Further, performing the steps of decoding (S) the received side information to generate transcoding guiding information, and encoding (S) a representation of the received video bitstream based at least on the generated transcoding guiding information, to provide a transcoded video bitstream with a predetermined output video format.

Method and arrangement for video transcoding using mode or motion or in-loop filter information

Delta quantized coefficients of a pixel block in a picture in a first representation of a video sequence are encoded based on information derived from estimated quantized coefficients for the pixel block. The delta quantized coefficients represent a difference between actual quantized coefficients of the pixel block derived by encoding at least a portion of the picture in the first representation of the video sequence and the estimated quantized coefficients. The estimated quantized coefficients represent a difference between a reconstructed block of a corresponding picture in a second representation of the video sequence and a prediction block obtained based on intra mode information and/or inter motion information derived by encoding the picture in the first representation of the video sequence.

Guided transcoding

A method of deriving parameters required for decoding a current layer of a coded multi-layer video sequence. The method comprises deriving a required parameter from one or more parameters associated with the current or a lower layer of the multiple layers. The invention makes use of an understanding that parameters which are required for decoding a current higher layer of a multi-layer video representation may be derived, i.e., inferred or predicted, from parameters associated with lower layers rather than explicitly signaled in a parameter set associated with the current layer. Also disclosed are a method of encoding parameters associated with such a current layer, corresponding computer program products, a corresponding parameter set decoder, and a corresponding parameter set encoder.

Encoding and deriving parameters for coded multi-layer video sequences

The embodiments relates to motion vector prediction and decoding for multi-view video content from multiple camera views (). At least one candidate motion vector predictor () is provided for a current motion vector () to be encoded. A motion vector predictor () is then determined from the at least one candidate motion vector predictor (). Correspondingly, during decoding a motion vector () is determined for a current pixel block () based on a motion vector predictor () determined for the current pixel block ().

Motion vector processing

It is presented a method for encoding a video frame of a piece of video content. The method is performed in an encoder device and comprises the steps of: dividing the video frame into a set of non-overlapping regions, wherein the set comprises at least one region; assigning each region, in the set of regions, to a separate processing unit; encoding, in each processing unit, picture data of the respective region; collecting progress data from each processing unit, the progress data indicating progress of the encoding of the respective region; and dividing a particular region into a plurality of smaller regions and assigning each smaller region to a separate processing unit, when the progress data indicates that progress of encoding the particular region is insufficient.

Encoding and decoding a video frame in separate processing units

Methods and arrangements for video coding are provided. In one exemplary embodiment, a method performed by a video decoder may include decoding an encoded video block based on a single index corresponding to the encoded video block and a predetermined reference picture list to obtain a decoded video block. Further, the index may represent a combination of a reference mode and one or more reference pictures associated with the predetermined reference picture list.

Method and arrangement for video coding

A method of identifying a parameter set for decoding a multi-layer video representation. The method includes identifying the parameter set based on a parameter set identifier and one or more layer identifiers indicating a layer of the video representation. Optionally, the method may further include returning the identified parameter set from a parameter set database, and activating the parameter set. Identifying parameter sets using both a parameter set identifier and one or more layer identifiers is advantageous in that the length of the parameter set identifier codeword may be shorter. This results in bitrate savings, since the number of bits which need to be transmitted is reduced. Corresponding computer program products and video decoders for decoding a multi-layer video representation are disclosed.

Identifying a parameter set for decoding a multi-layer video representation

View synthesis is performed based on obtained texture data and a depth map. The resolution of the depth map is lower than that of the texture data by a ratio dw in the x direction and by a ratio dh in the y direction. Texture pixel positions x, y are transformed into non-integer depth map pixel positions by performing divisions x/dw and y/dh and these non-integer depth map pixel positions are rounded to integer depth map pixel positions, and a view is synthesized based at least on the obtained texture data and depth map values at the integer depth map pixel positions and/or adjacent positions.

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Kista, Sweden

Thomas Rusert