Noise Resilient Local Gradient Orientation for Content-Based Image Retrieval

Table 5

Average retrieval precision and average retrieval recall of NRLGO by varying combinations of gradient orientation and color quantization levels by keeping contrast information fixed at 5 on Corel 5k in RGB.

Dataset	Performance	Distance or similarity metrics
		Chi-square	Square chord	MTH	Euclidean distance	Shepherd	Manhattan
Corel 1k	Precision (%)	73.5	76.70	83.45	97.91	83.20	83.50
	Recall (%)	8.64	9.20	10.01	11.75	9.98	10.02
Corel 5k	Precision (%)	55.42	52.89	59.64	19.91	64.00	65.8
	Recall (%)	6.83	6.34	7.15	2.39	7.68	7.89
Corel 10k	Precision (%)	47.91	40.96	49.93	10.00	52.72	53.07
	Recall (%)	5.53	4.91	5.99	12.00	6.32	6.36