Improved CNN-Based Hashing for Encrypted Image Retrieval

Table 3

Time consumption of retrieval.

Methods	Number of images in data collection
	2000	4000	6000	8000	10000
DLHEIR (48 bits)	0.58‬	0.742	0.908	1.073‬	1.249‬
DLHEIR (32 bits)	0.537‬	0.657‬	0.776‬	0.894	1.016‬
DLHEIR (24 bits)	0.505‬	0.608‬	0.637‬	0.799‬	0.908‬
DLHEIR (12 bits)	0.483‬	0.554‬	0.637‬	0.703‬	0.785‬
Xia (CSD)	2.51	4.60	6.26	8.34	10.49
Xia (SCD)	1.65	3.79	5.36	6.53	8.78
Qin	0.95	1.46	2.25	2.88	3.63