Signaling output indications in codec-hybrid multi-layer video coding

An enhancement layer video decoding device comprising:

• a memory configured to store video data;
• and
• one or more processors in communication with the memory and configured to:
• receive a bitstream including at least one enhancement layer of video data to be decoded, wherein the at least one enhancement layer is coded according to a first video codec standard,
• determine, from the bitstream, that a base layer of the video data is provided by an external system, wherein the base layer is coded according to a second video codec standard that is different than the first video codec standard,
• receive one or more base layer decoded pictures that belong to the base layer from the external system,
• store the one or more base layer decoded pictures received from the external system,
• decode enhancement layer pictures that belong to the at least one enhancement layer of the video data, wherein the one or more processors are configured to perform inter-layer prediction of one or more of the enhancement layer pictures using the one or more base layer decoded pictures stored at the enhancement layer video decoding device,
• determine, from the bitstream, one or more target output layers of the video data,
• based on the target output layers including the at least one enhancement layer, output the enhancement layer decoded pictures that belong to the at least one enhancement layer for display, and
• based on the base layer being provided by the external system, send an output indication from the enhancement layer video decoding device and to the external system indicating whether the base layer decoded pictures that belong to the base layer are to be output for display,
• wherein the enhancement layer video decoding device comprises a conforming video decoder for the first video codec standard where the base layer is provided externally and coded according to the second video codec standard that is different than the first video codec standard, and wherein the enhancement layer video decoding device is determined to comprise the conforming video decoder based on the one or more processors of the enhancement layer video decoding device receiving the one or more base layer decoded pictures that belong to the base layer from the external system, outputting the enhancement layer decoded pictures that belong to the at least one enhancement layer included as one of the target output layers, and sending the output indication to the external system.

An enhancement layer video encoding device comprising:

• a memory configured to store video data;
• and
• one or more processors in communication with the memory and configured to:
• determine that a base layer of the video data is provided by an external system, wherein the base layer is coded according to a first video codec standard,
• receive one or more base layer decoded pictures that belong to the base layer from the external system,
• store the one or more base layer decoded pictures received from the external system,
• encode enhancement layer pictures that belong to at least one enhancement layer of the video data, wherein the at least one enhancement layer is coded according to a second video codec standard that is different than the first video codec standard, and wherein the one or more processors are configured to perform inter-layer prediction of one or more of the enhancement layer pictures using the one or more base layer decoded pictures stored at the enhancement layer video encoding device, and
• generate a bitstream including the enhancement layer encoded pictures that belong to the at least one enhancement layer, an indication of whether the enhancement layer is a target output layer, and an indication that the base layer is provided by the external system, and without including any of the base layer decoded pictures that belong to the base layer in the bitstream,
• wherein the generated bitstream comprises a conforming bitstream for the second video codec standard where the base layer is provided externally and coded according to the first video codec standard that is different than the second video codec standard, and wherein the generated bitstream is determined to comprise the conforming bitstream based on the generated bitstream including the enhancement layer encoded pictures that belong to the at least one enhancement layer without including any of the base layer decoded pictures that belong to the base layer.