G06V30/00
Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
G06V30/00
Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
G06V30/18
Extraction of features or characteristics of the image
G06V30/18
Extraction of features or characteristics of the image
G06V30/18143
Extracting features based on salient regional features, e.g. scale invariant feature transform [SIFT] keypoints
G06V30/18143
Extracting features based on salient regional features, e.g. scale invariant feature transform [SIFT] keypoints
G06V30/18152
Extracting features based on a plurality of salient regional features, e.g. "bag of words"
G06V30/18152
Extracting features based on a plurality of salient regional features, e.g. "bag of words"