Abstract:

In order to solve the problem that traditional LDP algorithms is difficult to balance the effectiveness of feature extraction and the stability of feature encoding, an attractive local second gradient contours (ALSGC) face feature extraction algorithm was proposed.Firstly, the Kirsch operator was used to calculate the neighborhood edge response image of the face image.Secondly, an attraction descriptor was introduced and the local average gray value and global average gray value of the edge response image and the neighborhood center gray value was combined to complete the local attraction pattern encoding.The entire image was traversed to get the ALSGC face feature map, the ALSGC feature map was divided to blocks and the statistical histograms of different patterns for each block was obtained by calculation.Finally, the statistical histograms of all the blocks were cascaded to generate the corresponding feature vector and support vector machine was used to complete classification and recognition.The proposed algorithm not only overcame the insufficient effectiveness of LBP, LDP, LDN and other algorithms who extract first-gradient features, but also reduced the sensitivity to changes in expression, posture, occlusion, lighting and random noise of methods such as DLDP, CSLDP, GCSLDP who extracting second-gradient features.It better achieved the balance between the effectiveness of feature extraction and the stability of feature encoding, and took into account the recognition rate and robustness.

Key words: local attractive pattern, second gradient contours, Kirsch operator, feature extraction, face recognition