  Long Wave Infrared (LWIR) cameras provide images regardles of the ambient
illumination, they tolerate fog and are not blinded by the incoming car
headlights. These features make LWIR cameras attractive for autonomous
navigation, security and military applications. Thermal images can be used
similarly to the visible range ones, including 3D scene reconstruction with two
or more such cameras mounted on a rigid frame. There are two additional
challenges for this spectral range: lower image resolution and lower contrast
of the textures.
  In this work, we demonstrate quadocular LWIR camera setup, calibration, image
capturing and processing that result in long range 3D perception with 0.077 pix
disparity error over 90% of the depth map. With low resolution (160 x 120) LWIR
sensors we achieved 10% range accuracy at 28 m with 56 degrees horizontal field
of view (HFoV) and 150 mm baseline. Scaled to the now-standard 640 x 512
resolution and 200 mm baseline suitable for head-mounted application the result
would be 10% accuracy at 130 m.
