Optimizing searching of a previously viewed scene for a head-mounted display device

A method for optimizing searching of a previously viewed scene for a head-mounted display (HMD) device, comprising:

• receiving, by the HMD device, at least one input image, wherein the at least one input image includes a plurality of views corresponding to a real-world scene;
• determining, by the HMD device, landmarks included in the at least one input image received;
• retrieving, by the HMD device, a co-visibility graph corresponding to the landmarks included in the at least one input image received, the co-visibility graph determined being pre-stored in a memory of the HMD device, and the co-visibility graph comprising a plurality of levels, each level comprises nodes corresponding to at least one view of the plurality of views, and edges between the nodes corresponding to the co-visibility of the landmarks between the at least one view of the plurality of views;
• determining, by the HMD device, a correlation between the landmarks of the at least one input image with at least one level of the plurality of levels of the co-visibility graph;
• and
• detecting, by the HMD device, a pose of the HMD device based on the correlation.

A head-mounted display (HMD) device for optimizing searching of a previously viewed scene, comprising:

• a memory storing a program or at least one instruction;
• and
• at least one processor configure to individually or collectively execute the program or the at least one instruction;
• wherein the program or the at least one instruction, when executed individually or collectively by the at least one processor, cause the HMD device configured to:
• receive a plurality of views corresponding to a real-world scene;
• determine landmarks included in each view of the plurality of views;
• determine a co-visibility of the landmarks between different views of the plurality of views, the co-visibility indicating same landmarks being included in the different views of the plurality of views;
• generate a co-visibility graph based on the co-visibility of the landmarks between the different views of the plurality of views, the co-visibility graph comprising multiple levels, each level of the multiple levels comprises nodes corresponding to at least one view of the plurality of views, and edges between the nodes that represent the co-visibility of the landmarks between the at least one view of the plurality of views;
• and
• detect a pose of the HMD device based on the co-visibility graph of the real-world scene.