Automatic Traffic Data Collection under Varying Lighting and Temperature Conditions in Multimodal Environments: Thermal versus Visible Spectrum Video-Based Systems

Table 5

Detection and classification performance for different pavement temperatures—thermal camera.

Pavement temp.	Number of road users present	Number of missed instances/miss rate	Classifier trained on regular data		Classifier trained on thermal data		Improvement (% points)
			Precision	Recall	Precision	Recall	Precision	Recall
	Vehicle detection and classification
0°C–5°C	42	1/2.4%	56.3%	96.4%	67.4%	96.7%	11.2%	0.2%
20°C–25°C	58	0/0.0%	89.1%	100.0%	96.1%	100.0%	7.0%	0.0%
25°C–30°C	37	2/5.4%	67.6%	100.0%	83.9%	100.0%	16.2%	0.0%
30°C–35°C	20	0/0.0%	27.9%	100.0%	68.4%	100.0%	40.5%	0.0%
35°C–40°C	45	1/2.2%	35.6%	100.0%	67.5%	100.0%	31.9%	0.0%
40°C–45°C	31	1/3.2%	23.6%	100.0%	65.4%	100.0%	41.7%	0.0%
45°C–50°C	19	0/0.0%	12.1%	100.0%	47.6%	100.0%	35.5%	0.0%
Average			44.6%	99.5%	70.9%	99.5%	26.3 %	0.0%
	Cyclist detection and classification
0°C–5°C	10	0/0.0%	69.2%	90.0%	64.3%	100.0%	−4.9%	10.0%
20°C–25°C	33	0/0.0%	72.1%	96.9%	64.6%	96.9%	−7.5%	0.0%
25°C–30°C	22	0/0.0%	70.0%	46.7%	70.8%	94.4%	0.8%	47.8%
30°C–35°C	36	0/0.0%	93.8%	51.7%	75.8%	86.2%	−18.0%	34.5%
35°C–40°C	27	2/7.4%	88.9%	33.3%	67.9%	76.0%	−21.0%	42.7%
40°C–45°C	40	0/0.0%	88.9%	22.9%	83.8%	86.1%	−5.1%	63.3%
45°C–50°C	26	0/0.0%	100.0%	6.7%	85.0%	85.0%	−15.0%	78.3%
Average			83.3%	49.7%	73.2%	89.2%	−10.1%	39.5%
	Pedestrian detection and classification
0°C–5°C	286	4/1.4%	99.5%	89.5%	100.0%	92.0%	0.5%	2.5%
20°C–25°C	71	0/0.0%	100.0%	66.0%	100.0%	66.7%	0.0%	0.7%
25°C–30°C	39	0/0.0%	86.4%	67.9%	100.0%	66.7%	13.6%	−1.2%
30°C–35°C	53	3/5.7%	75.0%	42.9%	97.0%	74.4%	22.0%	31.6%
35°C–40°C	51	2/3.9%	62.5%	12.5%	96.7%	63.0%	34.2%	50.5%
40°C–45°C	44	2/4.5%	50.0%	23.3%	96.3%	70.3%	46.3%	46.9%
45°C–50°C	44	2/4.5%	61.1%	33.3%	100.0%	71.1%	38.9%	37.7%
Average			76.4%	47.9%	98.6%	72.0%	22.2%	24.1%
	Total detection and classification
			Accuracy		Accuracy		Accuracy
0°C–5°C	338	5/1.5%	90.3%		92.8%		2.6%
20°C–25°C	162	0/0.0%	86.3%		85.9%		-0.3%
25°C–30°C	98	3/3.1%	74.2%		84.4%		10.2%
30°C–35°C	109	3/2.7%	54.2%		82.4%		28.1%
35°C–40°C	123	5/4.1%	43.3%		76.5%		33.2%
40°C–45°C	115	3/2.6%	35.9%		82.2%		46.3%
45°C–50°C	89	2/2.2%	30.8%		79.4%		48.6%
Average			59.3%		83.4%		24.1%