A multi-layer or multi-view video (1) is encoded by encoding one of a picture (12) in a first layer or view (10) and a picture (22) in a second layer or view (20) coinciding at a switching point (2) defining a switch between the first layer or view (10) and the second layer or view (10). The other of the picture (12) in the first layer or view (10) and the picture (22) in the second layer or view (20) coinciding at the switching point is encoded as a skip picture. The embodiments thereby reduce complexity of encoding and decoding multi-layer or multi-view video (1) having a switching point (2) and reduce the number of bits required for representing encoded pictures coinciding at the switching point (2).

Systems, methods, and instrumentaliiies are provided to implement video coding system (VCS). The VCS may be configured to receive a video signal, which may include one or more layers (e.g., a base layer (BL) and/or one or more enhancement layers (ELs)). The VCS may be configured to process a BL picture into an inter-layer reference (ILR) picture, e.g., using picture level inter-layer prediction process. The VCS may be configured to select one or both of the processed IL R picture or an enhancement layer (EL) reference picture. The selected reference picture(s) may comprise one of the EL reference picture, or the ILR picture. The VCS may be configured to predict a current EL picture using one or more of the selected ILR picture or the EL reference picture. The VCS may be configured to store the processed ILR picture in an EL decoded picture buffer (DPB).

Multi-layer dependencies are signaled in an efficient way for a multi-view video stream(1). Coding or decoding relationship information defining coding or decoding dependencies is represented inbit-efficient syntax code, preferably through usage of hierarchical layer dependencies using layer indices for representing layer dependencies.

A video device may generate an enhanced inter-layer reference (E-ILR) picture io assist in predicting an enhancement layer picture of a. scalable bitstream. An E-ILR picture may include one or more E-ILR blocks. An E-ILR block may be generated using a differential method, a residual method, a bi-prediction method, and/or a uni-prediction method. The video device may determine a first time instance. The video device may subtract a block of a first base layer picture characterized by the first time instance from a block of an enhancement layer picture characterized by the first time instance to generate a differential block characterized by the first time instance. The video device may perform motion compensation on the differential block and add the motion compensated differential picture to a block of the second base layer picture characterized by the second time instance to generate an E-ILR. block.

In one example, the disclosure is directed to techniques that include receiving a bitstream comprising at least a syntax element, a first network abstraction layer unit type, and a coded access unit comprising a plurality of pictures. The techniques further include determining a value of the syntax element which indicates whether the access unit was coded using cross-layer alignment. The techniques further include determining the first network abstraction layer unit type for a picture in the access unit and determining whether the first network abstraction layer unit type equals a value in a range of type values. The techniques further include setting a network abstraction layer unit type for all other pictures in the coded access unit to equal the value of the first network abstraction layer unit type if the first network abstraction layer unit type is equal to a value in the range of type values.

An apparatus for coding video information according to certain aspects includes a memory unit and a video processor in communication with the memory unit. The video processor is configured to identify a first picture included in the first set of pictures, wherein pictures within the first set of pictures having an output position after the output position of the first picture also have a decoding position after the decoding position of the first picture. The video processor is further configured to identify a second picture included in the second set of pictures, wherein pictures within the second set of pictures having an output position after the output position of the second pictures also have a decoding position after the decoding position of the second picture. The video processor is also configured to code the identified first picture and the identified second picture via one syntax element into one access unit.