Infrared Thermography Approach for Effective Shielding Area of Field Smoke Based on Background Subtraction and Transmittance Interpolation

Abstract

Effective shielding area is a crucial indicator for the evaluation of the infrared smoke-obscuring effectiveness on the battlefield. The conventional methods for assessing the shielding area of the smoke screen are time-consuming and labor intensive, in addition to lacking precision. Therefore, an efficient and convincing technique for testing the effective shielding area of the smoke screen has great potential benefits in the smoke screen applications in the field trial. In this study, a thermal infrared sensor with a mid-wavelength infrared (MWIR) range of 3 to 5 μm was first used to capture the target scene images through clear as well as obscuring smoke, at regular intervals. The background subtraction in motion detection was then applied to obtain the contour of the smoke cloud at each frame. The smoke transmittance at each pixel within the smoke contour was interpolated based on the data that was collected from the image. Finally, the smoke effective shielding area was calculated, based on the accumulation of the effective shielding pixel points. One advantage of this approach is that it utilizes only one thermal infrared sensor without any other additional equipment in the field trial, which significantly contributes to the efficiency and its convenience. Experiments have been carried out to demonstrate that this approach can determine the effective shielding area of the field infrared smoke both practically and efficiently.

Phased array ultrasonic S-scan testing of near-detection-surface defects based on a background subtraction algorithm

“…The background subtraction algorithm works on the principle of subtracting a background image from the to-be-processed image to obtain a target image without background interference. It is commonly used in foreground detection for machine vision [22][23][24]. The calculation procedure is shown in equation (1):…”

Design and Evaluation of Screening Smoke Compositions Based on Red Phosphorus in Open Field Conditions

“…Experimental values of concentration and screening time highlighted the fact that pyrotechnic mixtures based on red phosphorus have a higher screening efficiency in VIS, the screening time being given by the stability of the smokescreens dispersed in the environment (depending on the wind speed and direction). The maximum VIS screening time can only be determined under field conditions for a wind speed value less than 3 m/s [28][29][30]. The screening effect occurs in VIS from the moment the smoke curtain was generated, and the area of interest was covered, whereas the screening effect occurred in IR from the moment the pyrotechnic mixture was ignited.…”

Technique based on the grayscale value for evaluating the shielding performance of infrared smokescreen

“…Currently, researchers mainly use the transmittance interpolation method to obtain the effective shielding area of the smokescreen. 30 Tang et al 31 extracted the effective shielding area of the smokescreen from the infrared images by combining background subtraction and transmittance interpolation methods. Cai et al 32 analyzed the error of the transmittance date matrix interpolation method and proposed a new method to measure the forming time of the color smokescreen using the color smokescreen RGB date matrix, which improved the measurement accuracy.…”

“…Currently, researchers mainly use the transmittance interpolation method to obtain the effective shielding area of the smokescreen 30 . Tang et al 31 . extracted the effective shielding area of the smokescreen from the infrared images by combining background subtraction and transmittance interpolation methods.…”