Adaptive resolution coding for video coding

Method of transmitting a bitstream comprising encoded representations of pictures of a first and second resolution version of a video to a device, the method comprising:

• transmitting a bitstream to the device, the bitstream comprising an encoded representation of first pictures of the first resolution version, the device comprising a decoder apparatus for decoding the encoded representation of first pictures into first pictures, the first pictures being associated with corresponding second pictures of the second resolution version of the video, each of the first pictures being a first spatially subsampled version of a corresponding second picture of the second resolution version, the subsampling being based on a first sampling lattice selected from a plurality of sampling lattices of a spatial subsampling scheme;
• transmitting signalling information to the device, the signalling information informing the decoder apparatus about a termination of receiving the encoded representations of the first pictures and the start of receiving of encoded representations of second pictures of the second resolution version,
• the signalling information further identifying at least one of the first pictures of the first resolution version as a first base picture and identifying one or more auxiliary pictures, the first base picture being associated with a corresponding second picture of the second resolution version, and, each of the one or more auxiliary pictures being a second spatially subsampled version of the corresponding second picture of the second resolution version, the subsampling being based on one or more further sampling lattices of the plurality of sampling lattices of the spatial subsampling scheme;
• transmitting an encoded representation of the one or more auxiliary pictures in the bitstream to the device for the decoder apparatus to decode the encoded representation of the one or more auxiliary pictures into one or more auxiliary pictures and construct a reference picture of the second resolution version based on the first base picture and the one or more auxiliary pictures;
• and,
• transmitting an encoded representation of second pictures in the bitstream to the device for decoding at least part of the encoded representation of the second pictures into one or more second pictures based on the reference picture.

A decoder apparatus for decoding encoded representations of pictures of a first and second resolution version of a video, the decoder apparatus comprising:

• a computer readable storage medium having computer readable program code embodied therewith, and a processor coupled to the computer readable storage medium, wherein responsive to executing the computer readable program code, the processor is configured to perform executable operations comprising:
• receiving a bitstream comprising encoded representations of first pictures of the first resolution version, each of the first pictures being a first spatially subsampled version of a corresponding second picture of the second resolution version, the subsampling being based on a first sampling lattice selected from a plurality of sampling lattices of a spatial subsampling scheme;
• decoding the encoded representations of the first pictures into first pictures;
• receiving signalling information, the signalling information informing the decoder apparatus about a termination of receiving the encoded representations of the first pictures and the start of receiving of encoded representations of second pictures of the second resolution version,
• the signalling information further identifying at least one of the first pictures of the first resolution version as a first base picture and identifying one or more auxiliary pictures, the first base picture being associated with a corresponding second picture of the second resolution version, and, each of the one or more auxiliary pictures being a second spatially subsampled version of the corresponding second picture of the second resolution version, the subsampling being based on one or more further sampling lattices of the plurality of sampling lattices of the spatial subsampling scheme;
• receiving an encoded representation of the one or more auxiliary pictures in the bitstream, decoding the encoded representation of the one or more auxiliary pictures into one or more auxiliary pictures and constructing a reference picture of the second resolution version based on the first base picture and the one or more auxiliary pictures;
• and,
• receiving an encoded representation of second pictures in the bitstream and decoding at least part of the encoded representation of the second pictures into one or more second pictures using the reference picture.

A video transmission module for transmitting a bitstream comprising encoded representations of pictures of a first and second resolution version of a video to a device, the video transmission module comprising:

• a computer readable storage medium having computer readable program code embodied therewith, and a processor coupled to the computer readable storage medium, wherein responsive to executing the computer readable program code, the processor is configured to perform executable operations comprising:
• transmitting a bitstream to the device, the bitstream comprising an encoded representation of first pictures of the first resolution version, the device comprising a decoder apparatus for decoding the encoded representation of first pictures into first pictures, the first pictures being associated with corresponding second pictures of the second resolution version of the video, each of the first pictures being a first spatially subsampled version of a corresponding second picture of the second resolution version, the subsampling being based on a first sampling lattice selected from a plurality of sampling lattices of a spatial subsampling scheme;
• transmitting signalling information to the device, the signalling information informing the decoder apparatus about a termination of receiving the encoded representations of the first pictures and the start of receiving of encoded representations of second pictures of the second resolution version,
• the signalling information further identifying at least one of the first pictures of the first resolution version as a first base picture and identifying one or more auxiliary pictures, the first base picture being associated with a corresponding second picture of the second resolution version, and, each of the one or more auxiliary pictures being a second spatially subsampled version of the corresponding second picture of the second resolution version, the subsampling being based on one or more further sampling lattices of the plurality of sampling lattices of the spatial subsampling scheme;
• transmitting an encoded representation of the one or more auxiliary pictures in the bitstream to the device for the decoder apparatus to decode the encoded representation of the one or more auxiliary pictures into one or more auxiliary pictures and construct a reference picture of the second resolution version based on the first base picture and the one or more auxiliary pictures;
• and,
• transmitting an encoded representation of second pictures in the bitstream to the device for decoding at least part of the encoded representation of the second pictures into one or more second pictures based on the reference picture.

A bitstream construction module comprising:

• a computer readable storage medium having computer readable program code embodied therewith, and a processor coupled to the computer readable storage medium, wherein responsive to executing the computer readable program code, the processor is configured to perform executable operations comprising:
• constructing a bitstream comprising encoded representations of pictures of a first and second resolution version of a video, the bitstream comprising a resolution change from an encoded representation of first pictures of the first resolution version of the video to an encoded representation of second pictures of the second resolution version of the video;
• and,
• transmitting the bitstream to a decoder apparatus, wherein the bitstream comprises:
• an encoded representation of the first pictures, the first pictures being associated with corresponding second pictures of the second resolution version of the video, each of the first pictures being a first spatially subsampled version of a corresponding second picture of the second resolution version, the subsampling being based on a first sampling lattice selected from a plurality of sampling lattices of a spatial subsampling scheme;
• signalling information for informing a decoder apparatus about a termination of receiving the encoded representations of the first pictures and the start of receiving of encoded representations of second pictures of the second resolution version,
• the signalling information further identifying at least one of the first pictures of the first resolution version as a first base picture and identifying one or more auxiliary pictures, the first base picture being associated with a corresponding second picture of the second resolution version, and, each of the one or more auxiliary pictures being a second spatially subsampled version of the corresponding second picture of the second resolution version, the subsampling being based on one or more further sampling lattices of the plurality of sampling lattices of the spatial subsampling scheme;
• an encoded representation of the one or more auxiliary pictures for the decoder apparatus to decode the encoded representation of the one or more auxiliary pictures into one or more auxiliary pictures and construct a reference picture of the second resolution version based on the first base picture and the one or more auxiliary pictures;
• and,
• an encoded representation of second pictures wherein at least part of the encoded representation of the second pictures can be decoded by the decoder apparatus into one or more second pictures based on the reference picture.