Histogram methods and systems for object recognition

摘要

A multidimensional histogram is used to characterize an image (or object), and is used to identify candidate matches with one or more reference images (or objects). An exemplary implementation employs hue information for two of the dimensions, and a second derivative function based on luminance for a third dimension. The simplicity and speed of the detailed arrangements make them well suited for use with cell phones and other mobile devices, which can use the technology for image/object recognition, e.g., in visual search applications.

主权项

1. A method for matching test imagery to reference imagery, comprising the acts:
generating color histogram data that corresponds to test imagery captured by a camera-equipped mobile device; matching said test imagery color histogram data with color histogram data that corresponds to reference imagery, said matching being performed by a hardware processor of said camera-equipped mobile device; said test imagery histogram data and said reference imagery histogram data comprising values corresponding to a plurality of quantized bins; and said matching including determining one or more of the following:
a. a number of occupied bins in the test and reference imagery histograms;b. a number of occupied bins common to both the test imagery and reference imagery histograms;c. a number of occupied bins combined between both the test imagery and reference imagery histograms;d. a number of pixels common to both the test imagery and reference imagery histograms (histogram intersection);e. a percentage of occupied bins of the test imagery histogram that are occupied in the reference imagery histogram;f. a ratio of said histogram intersection to number of occupied bins of the test imagery histogram;g. nonzero bins of test imagery histogram;h. nonzero bins of reference imagery histogram;i. nonzero bins of test imagery histogram that are a subset of nonzero bins of reference imagery histogram;j. a number of nonzero bins of test imagery histogram that are a subset of nonzero bins of reference imagery histogram;k. nonzero bins of reference imagery histogram that are a subset of nonzero bins of test imagery histogram; andl. a number of nonzero bins of reference imagery histogram that are a subset of nonzero bins of test imagery histogram.