IR-Band Conversion of Target and Background Using Surface Temperature Estimation and Error Compensation for Military IR Sensor Simulation

Abstract

Military infrared (IR) imaging systems utilize one or more IR wavelength-bands, among short wavelength IR (SWIR), middle wavelength IR (MWIR), and long wavelength IR (LWIR) band. The IR image wavelength-band conversion which transforms one arbitrary IR wavelength-band image to another IR wavelength-band image is needed for IR signature modeling and image synthesis in the IR systems. However, the IR wavelength-band conversion is very challenging because absorptivity and transmittance of objects and background (atmosphere) are different according to the IR wavelength band and because radiation and reflectance characteristics of the SWIR are very different from the LWIR and MWIR. Therefore, the IR wavelength-band conversion in this paper applies to only IR targets and monotonous backgrounds at a long distance for military purposes. This paper proposes an IR wavelength-band conversion method which transforms one arbitrary IR wavelength-band image to another IR wavelength-band image by using the surface temperature estimation of an object and the error attenuation method for the estimated temperature. The surface temperature of the object is estimated by an approximated Planck’s radiation equation and the error of estimated temperature is corrected by using the slope information of exact radiance along with the approximated one. The corrected surface temperature is used for generating another IR wavelength-band image. The verification of the proposed method is demonstrated through the simulations using actual IR images obtained by thermal equipment.

Detection and evaluation of the fibers' deposition parameters during wet filament winding

“…Since the temperature decreases after the deposition, the contrast between the incoming fiber-band and the already deposited fiber (background) is achieved by a temperature difference. [20] Thus, a clear contrast has been characterized around ΔT equal to 8 C. Nevertheless, during the winding, a clear contrast cannot be always achieved, which difficult the accurate identification of the fiber-band. For these reasons, filter algorithms based on image gamma correction are implemented.…”

“…[ 15–17 ] However, the quality of the image is highly dependent on the contrast between the tracking object, that is, fiber‐band, and the background. [ 18–20 ]…”

“…[15][16][17] However, the quality of the image is highly dependent on the contrast between the tracking object, that is, fiber-band, and the background. [18][19][20] This article intends to expand the understanding of the wet-winding of carbon fiber-reinforced plastics (CFRP) through the studying of the fiber-bandwidth and its winding-angle during a circumferential winding pattern. An IR-optical system is implemented and the influence of the winding speed and resin temperature on the acquired images are analyzed.…”

IR Composite Image Generation by Wavelength Band Based on Temperature Synthesis Estimated from IR Target Signature and Background Scene

“…And Cox et al [23] modeled an aircraft, a cloud, a background, and a sensor for generating an IR scene. Bae et al [24] studied an IR-WB conversion technique for military IR sensor simulation. In this study, real targets as well as modeled targets by RadThermIR [25] were used and the mentioned IR-WB conversion technique [24] was applied for the synthesis of IR targets and backgrounds.…”