Telefonaktiebolaget Lm Ericsson (publ)

Velos Media, LLC

Sharp Kabushiki Kaisha Corporation

Jonatan Samuelsson

Rickard Sjöberg

Kenneth Andersson

Jacob Ström

Martin Pettersson

Per Wennersten

Ruoyang Yu

Clinton Priddle

Rickard Sjoberg

Thomas Rusert

Magnus Westerlund

Per Frojdh

Bo Burman

Per Hermansson

Jack Enhorn

Sachin G Deshpande

Richard Mitic

Ying Wang

Christopher Hollmann

Kristofer Dovstam

Richard Sjöberg

Simon Ekström

Olie Baumann

A method performed by a video encoder for encoding a current picture belonging to a temporal level identified by a temporal_id. The method includes determining a Reference Picture Set (RPS) for the current picture indicating reference pictures that are kept in a decoded picture buffer (DPB) when decoding the current picture, and when the current picture is a temporal switching point. The method further includes operating to ensure that the RPS of the current picture includes no picture having a temporal_id greater than or equal to the temporal_id of the current picture.

Arrangements and methods of encoding picture belonging to a temporal level

According to an embodiment, an encoder is configured to ensure that for each long-term picture of a RPS of a picture i the value of a flag referred to as delta_poc_msb_present_flag[i] is equal to 1 when there are at least two reference pictures in a decoded picture buffer with lsb's of the POC referred to as pic_order_cnt_lsb equal to the lsb's of the respective long-term picture i denoted POC lsbLt[i]. When the delta_poc_msb_present_flag is equal to 1, the long-term picture is indicated by the full POC.

Encoder, decoder and methods thereof for video encoding and decoding

A device may be configured to signal downsampling offset information for coded video in a phase indication information message. A device may be configured to receive the phase indication information message. The phase indication message may apply to a current cropped decoded picture and persist for all subsequent pictures of a current layer in output order with the same cropped picture width and cropped picture height as the current cropped decoded picture until a picture in the current layer with an associated phase indication information message and the same cropped picture width and cropped picture height as the current cropped decoded picture is output and follows the current picture in output order.

Systems and methods for signaling downsampling offset information in video coding

An encoded representation of a picture of a video stream is decoded by retrieving buffer description from the encoded representation. The buffer description information is used to determine at least one picture identifier identifying a respective reference picture as decoding reference for the picture. A decoded picture buffer is updated based on the determined picture identifier. The encoded representation of the picture itself comprises the information needed by a decoder to identify the reference pictures required to decode the encoded representation.

Reference picture signaling

The solution presented herein defines from which previously decoded picture to retrieve the values for calculating POC of the current picture regardless of how many temporal layers have been decoded. That is achieved by determining the POC of the current picture, to be used by the decoder, as a sum of a syntax element pic_order_cnt_lsb and most significant bits of the POC, PicOrderCntMsb, of the current picture, wherein the PicOrderCntMsb of the current picture is derived using at least a prevPicOrderCntMsb and a prevPicOrderCntLsb and the prevPicOrderCntMsb is set equal to the most significant bits of the POC of a previous reference picture in decoding order that has a layer identity equal to zero and prevPicOrderCntLsb is set equal to the value of the least significant bits of the POC of a previous reference picture in decoding order that has a layer identity equal to zero.

Decoders and methods thereof for managing pictures in video decoding process

An encoder calculates an indication to a previous reference picture having temporal identity of zero. The encoder creates a first set of indicators to the previous reference picture, to all reference pictures in a first reference picture set of the previous reference picture, and to all pictures following the previous reference picture in decoding order and precede the current picture in decoding order. The encoder sets a flag for picture order count cycle, when a long term reference picture (LTRP) has least significant bits (LSBs) of a picture order count, for which more than one picture in the first set share same value of the LSBs of picture order count as the LTRP. The decoder obtains LSB of a picture order count for a LTRP in a reference picture set of the current picture. The decoder concludes non-compliant bitstream based on indications provided by the flag.

Decoder and encoder and methods for coding of a video sequence

A length indicator associated with an encoded representation of a slice is parsed. The length indicator is indicative of a length of an extension field present in a slice header of the encoded representation. A decoder can then determine to ignore, during decoding of the encoded representation, any value of the extension field in the slice header where these values are identified based on the length indicator. As a consequence, an extension field can be added to slice headers and still enable legacy decoders to correctly decode the encoded representations.

Extension data handling

The present embodiments introduce a new type of random access point in video bitstreams that can be used for random access operations but can be represented in encoded form at a lower bit-cost as compared to IRAP pictures. The random access point is a dependent random access point (DRAP) picture that is encoded and decoded using an IRAP picture and/or a previous, according to a decoding order, DRAP picture as sole reference picture(s) for the DRAP picture. The DRAP picture is encoded as a trailing picture that may be used for reference and constitutes a random access point in a video bitstream.

Dependent random access point pictures

An object of the embodiments is to achieve an improved reference picture handling. That is achieved by taking into account whether the reference pictures in the decoded picture buffer are long-term reference pictures or short-term reference pictures when determining how they should be marked when the information of the reference picture set is received. The reference pictures are marked as 'used for short-term reference' or “used for long-term reference” in the Decoded Picture Buffer (DPB) depending on whether they are included as short-term pictures or long-term pictures in the RPS of a current picture.

Encoder and decoder and methods thereof for encoding/decoding a picture of a video sequence

Arrangements and methods thereof for processing video

An encoder is configured to encode a representation of a current picture of a video stream of multiple pictures. The encoder is further configured to encode, for each of a plurality of reference pictures included in a buffer description for the current picture, a respective one-bit flag according to one of two available values for the one-bit flag. The two available values for the one-bit flag include a first value explicitly indicating to a decoder to include the reference picture in a reference picture list for decoding the current picture. The two available values for the one-bit flag further include a second value explicitly indicating to the decoder not to include the reference picture in the reference picture list for decoding the current picture. The encoder is further configured to output the representation of the current picture and the one-bit flags.

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Stockholm, Sweden

Jonatan Samuelsson