71
Network Camera User Manual
No sound can be heard.
A
：
Audio input device is not connected. Please connect and try again.
B: Audio function is not enabled at the corresponding channel. Please enable this function.
Appendix 2 Common Material Emissivity
Material
Emissivity
Material
Emissivity
Human Skin
0.98
Brick
0.95
Printed Circuit Board
0.91
Sand
0.90
Concrete
0.95
Soil
0.92
Ceramic
0.92
Cloth
0.98
Rubber
0.95
Hard Paperboard
0.90
Paint
0.93
White Paper
0.90
Wood
0.85
Water
0.96
Pitch
0.96
Flame
0.2~0.3
The material emissivity is also affected by the surface of the material.
Material Surface
Emissivity
Rough
0.95
Slightly Rough
0.8
Slightly Smooth
0.6
Smooth
0.3
