Methods and apparatus to count people in images

A tangible computer readable storage medium comprising instructions that, when executed, cause a processor to at least:

• form blobs based on whitened pixels of detected face rectangles in pairs of frames of a plurality of image frames captured over a period of time, respective ones of the pair of frames including one frame obtained with a first image sensor and another frame obtained with a second image sensor;
• calculate locations of centers of the blobs in each frame of the pairs of frames;
• eliminate respective ones of the blobs from a first set of blobs in a first frame of a first one of the pairs of frames, the respective ones of the blobs to be eliminated from the first set having locations within an overlap region corresponding to an intersection of a first field of view of the first image sensor and a second field of view of the second image sensor;
• and
• add a number of blobs remaining in the first set of blobs of the first frame of the first one of the pairs of frames to a number of blobs in a second set of blobs of a second frame of the first one of the pairs of frames to detect a blob people count represented in the first one of the pairs of frames.

A method, comprising:

• forming, by executing an instruction with a processor, blobs based on whitened pixels of detected face rectangles in pairs of frames of a plurality of image frame captured over a period of time, respective ones of the pair of frames including one frame obtained with a first image sensor and another frame obtained with a second image sensor;
• calculating, by executing an instruction with the processor, locations of centers of the blobs in each frame of the pairs of frames;
• eliminating, by executing an instruction with the processor, blobs from a first set of blobs in a first frame of a first one of the pairs of frames, the respective ones of the blobs to be eliminated from the first set having respective locations within an overlap region corresponding to an intersection of a first field of view of the first image sensor and a second field of view of the second image sensor;
• and
• adding, by executing an instruction with the processor, a number of blobs remaining in the first set of blobs of the first frame of the first one of the pairs of frames to a number of blobs in a second set of blobs of a second frame of the first one of the pairs of frames to form a blob people count represented in the first one of the pairs of frames.