This paper presents a further improvement of the previously published technique, PP-RIDER (Partial Palmprint Rotation-Invariant and DEgraded Recognition). PP-RIDER technique combines Modified Phase-Only Correlation (MPOC) and Fourier-Mellin Transform (FMT), and was proposed for recognizing randomly-rotated and degraded partial palmprints with respect to full palmprints registered in a database.
In this paper, the influence of the inside-lobe size for the MPOC technique in PP-RIDER is analyzed. In fact, MPOC may produce spurious peaks around the main correlation peak which, when using too small inside-lobe sizes, can affect negatively the similarity scores in genuine comparisons. The proposed improved version of PP-RIDER is tested using the modified THUPALMLAB and PV-TEST-PARTIAL databases. The experimental results show that the proposed modifications allow achieving an improved performance when compared to the baseline technique.