Coding of feature location information

A mobile device, comprising:

• an image module configured to obtain an image;
• a visual search module configured to generate encoded feature location information of the image;
• and
• a controller configured to communicate the encoded feature location information of the image to a server via a wireless network;
• wherein the visual search module includes
• logic for generating a hexagonal grid, wherein the hexagonal grid includes a plurality of hexagonal cells;
• logic for quantizing feature locations of an image using the hexagonal grid, wherein the logic for quantizing feature locations comprises:
• for each feature location, logic for generating transformed coordinates of the feature location from a two dimensional plane to a three dimensional space, logic for rounding the transformed coordinates to corresponding nearest integers, and logic for verifying the transformed coordinates belong to a hexagonal plane in the three dimensional space;
• logic for generating a histogram to record occurrences of feature locations in each hexagonal cell;
• and
• logic for encoding the histogram in accordance with the occurrences of feature locations in each hexagonal cell.

A mobile device, comprising:

• an image module configured to obtain an image;
• a visual search module configured to generate encoded feature location information of the image;
• and
• a controller configured to communicate the encoded feature location information of the image to a server via a wireless network;
• wherein the visual search module includes
• means for generating a hexagonal grid, wherein the hexagonal grid includes a plurality of hexagonal cells;
• means for quantizing feature locations of an image using the hexagonal grid, wherein means for quantizing feature locations comprises:
• for each feature location, means for generating transformed coordinates of the feature location from a two dimensional plane to a three dimensional space, means for rounding the transformed coordinates to corresponding nearest integers, and means for verifying the transformed coordinates belong to a hexagonal plane in the three dimensional space;
• means for generating a histogram to record occurrences of feature locations in each hexagonal cell;
• and
• means for encoding the histogram in accordance with the occurrences of feature locations in each hexagonal cell.

A computer program product for coding feature location information of an image, comprising a non-transitory medium storing computer programs for execution by one or more computer systems, the computer program product comprising:

• code for generating a hexagonal grid, wherein the hexagonal grid includes a plurality of hexagonal cells;
• code for quantizing feature locations of an image using the hexagonal grid, wherein code for quantizing feature locations comprises:
• for each feature location, code for generating transformed coordinates of the feature location from a two dimensional plane to a three dimensional space, code for rounding the transformed coordinates to corresponding nearest integers, and code for verifying the transformed coordinates belong to a hexagonal plane in the three dimensional space;
• code for generating a histogram to record occurrences of feature locations in each hexagonal cell;
• and
• code for encoding the histogram in accordance with the occurrences of feature locations in each hexagonal cell.