Research Article

Efficient ConvNet Feature Extraction with Multiple RoI Pooling for Landmark-Based Visual Localization of Autonomous Vehicles

Table 3

Localization accuracy comparison of MRoI-FastRCNN-AlexNet versus AlexNet and MRoI-FastRCNN-VGG-M1024 versus VGG-M1024 in terms of maximum precision at 100% recall (Pr. at 100% Re.), maximum recall at 100% precision (Re. at 100% Pr.), and average precision (AP). The highest value with respect to each metric on each dataset is highlighted in bold. The middle italic values are the difference between MRoI-FastRCNN-AlexNet/VGG-M1024 and AlexNet/VGG-M1024.

Method UACampus St. Lucia Nordland Mapillary
Pr. at 100% Re. Re. at 100% Pr. AP Pr. at 100% Re. Re. at 100% Pr. AP Pr. at 100% Re. Re. at 100% Pr. AP Pr. at 100% Re. Re. at 100% Pr. AP

MRoI-FastRCNN- AlexNet 98.9% 98.6% 99.7% 89.3% 68.2% 98.2% 75.2% 34.0% 92.1% 72.6% 31.2% 90.4%
+3.4% +7.3% +0.3% +2.7% +3.1% +0.7% +5.7% +15.4% +4.6% −0.8% −2.2% −1.1%
AlexNet 95.5% 91.3% 99.4% 86.6% 65.1% 97.5% 69.5% 18.6% 87.5% 73.4% 33.4% 91.5%

MRoI-FastRCNN- VGG-M1024 98.3% 92.0% 99.6% 89.5% 74.4% 98.3% 75.0% 36.7% 92.3% 73.1% 24.3% 90.7%
+3.8% +7.0% +0.5% +8.2% +28.1% +2.6% +4.5% +12.2% +3.5% −1.2% −3.6% −1.3%
VGG-M1024 94.5% 85.0% 99.1% 81.3% 46.3% 95.7% 70.5% 24.5% 88.8% 74.3% 27.9% 92.0%