• ETRI Journal
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• 제37권5호
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• pp.1023-1031
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• 2015

In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

• 전기학회논문지
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• 제64권7호
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• pp.1031-1039
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• 2015

Present guided missiles are equipped with infrared seeker to find the infrared sources radiating from target plane and then chase, which results in an improvement of the hitting success rate when in striking target objects. To interrupt the chases from the guided missile, the target plane spreads the flare, avoiding the missile attracts. Our research is to develop a 2-color infrared identification technique to discern the flare and real thermal source from target plane. Considering flare radiation properties and EM atmosphere transmission rates, two channels were selected, in which main channel (MC) was in a range of 3.7 μm∼4.8 μm and auxiliary channel (AC) in 1.7 μm∼2.3 μm. A 2500K heat source was used for an artificial flare source, while a 570K heat source was utilized for airplane infrared source in experimental testing. Two infrared sensors detectable only at each chanel were employed in order to measure the voltage ratio from two channels, identifying the flare and real target plane via comparison the voltage ratio. Several experimental conditions were imported in order to prove that our proposed 2-color infrared identification technique is very efficient way to discern heat sources from aircraft and flare, demonstrating that our proposed technique is very promising means for our force’s InfraRed Counter Counter Measure (IRCCM) in order to countermeasure opposite force’s InfraRed Counter Measures (IRCM).

• 한국군사과학기술학회지
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• 제16권2호
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• pp.207-213
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• 2013

An infrared image synthetic method is proposed for infrared system simulation. The synthesis image uses a background IR image captured from real scene and a target IR modeling image. The radiances related with maximum and minimum temperatures of the background and target images are calculated from the Planck's blackbody equation. Based on them, the background and target images are compensated and synthesized. The proposed method is simulated and the IR target images are generated by RadThermIR software.

• 전자공학회논문지SC
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• 제49권3호
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• pp.53-61
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• 2012

본 논문에서는 스테레오 적외선 카메라를 이용하여 소형 및 고온으로 날아가는 이동체의 거리를 실시간으로 측정하는 시스템을 제안한다. 이동체와 주변 환경의 온도 차이를 측정하고 고속으로 이동하는 소형 이동체의 거리를 자동으로 측정하기 위하여 적외선 스테레오 카메라 시스템을 구축하였다. 우선 적외선 카메라를 이용하여 취득한 고온의 이동체 영상으로부터 주변의 온도분포와 이동체간의 온도차를 이용하여 이동체영역을 검출하고, 이동체의 움직임 정보와 적외선 카메라 영상의 밝기정보를 결합하여 이동체를 추적한다. 좌우 적외선 카메라 영상에 대하여 각각 추출된 이동체 영역을 중심으로 스테레오 정합을 수행하여 시차정보를 추정하고, 카메라 파라미터와 시차정보를 이용하여 실시간으로 이동하는 이동체의 거리를 추정한다. 본 논문에서 제안하는 적외선 스테레오 카메라 시스템을 검증하기 위하여 고온의 이동체를 촬영할 때, 3차원 궤적(x,y,z) 측정기를 함께 가동하여 이동체가 이동하는 거리를 측정하여 이를 기준 거리(ground truth)로 설정하였다. 3차례의 비디오 데이터로부터 실험한 결과, 적외선 스테레오 카메라를 이용한 고온/소형 이동체의 거리오차 측정 결과는 평균적으로 9.68%로 추정되었다. 스테레오 적외선 카메라의 타이밍 문제(jitter)를 고려하면, 실제로 추정 오차는 줄어들 것으로 판단되기 때문에, 향후 적외선 카메라를 이용하는 다양한 이동체의 거리 및 위치를 측정하는데 응용할 수 있을 것으로 기대된다.

• 제어로봇시스템학회논문지
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• 제21권9호
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• pp.836-842
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• 2015

In this paper, the target size and model based target size estimator (TMBE) algorithm is presented for iimaging infrared (IIR) seeker. At the imaging seeker, target size information is important factor for accurate tracking. The model based target size estimator filter (MBEF) algorithm was proposed to estimate target size at imaging infrared seeker. But, the model based target size estimator filter algorithm need to know relative distance from the target. In order to overcome the problem, we propose target size and model based target size estimator filter (TMBEF) algorithm which based on the target size. The performance of proposed algorithm is tested at target intercept scenario. The experiment results show that the proposed algorithm has the accurate target size estimating performance.

• 한국통신학회논문지
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• 제38B권9호
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• pp.736-743
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• 2013

적외선 탐색 및 추적 시스템에서 원거리에 표적이 존재할 경우 표적의 크기가 매우 작고, 해무와 같은 클러터와 다양한 센서 잡음으로 인해 표적의 검출이 매우 어렵다. 특히 표적의 화소 값과 유사한 잡음이나 클러터가 존재하는 경우 일반적인 임계화 기법을 적용하는 경우 표적의 오검출 위험이 매우 높다. 이러한 이유로 본 논문에서는 영상의 밝기 정보와 표적에 대한 사전 정보를 이용하여 최적의 표적 검출 결과를 도출하기 위한 적응적 임계화 기법을 제안한다. 소형 표적을 강조하기 위하여 인간 시각 시스템을 반영한 CSF(Contrast Sensitivity Function)를 적용하고, 표적이 강조된 영상에서 영상의 밝기 정보와 거리 정보를 이용하여 표적을 검출한다. 다양한 환경 조건에서 획득된 적외선 영상에 대한 실험 결과들은 제안 알고리즘의 견실한 성능을 보여준다.

• 제어로봇시스템학회논문지
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• 제20권8호
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• pp.842-848
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• 2014

In this paper, an improved method RMBE (Resizable Model Based target size Estimator) is presented for SDIIR (Strap Down Imaging Infrared) seekers. At the target engaging scenario, the IIR target measurement is separated by various parts. In this case, target object changing is important to accurate target intercept. Therefore, we need robust target size estimator. Our proposed method resize estimated target size with MC-1 (Markov Chain I) for accurate target size estimation. The performance of proposed method is tested at IIR target tracking of target intercept scenario. The experiment results show that the proposed RMBE has improved performance than MBE.

• 한국산업융합학회 논문집
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• 제26권6_2호
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• pp.1073-1082
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• 2023

Thermal sensors, also called thermal infrared wavelength sensors, measure temperature based on the intensity of infrared signals that reach the sensor. The infrared signals recognized by the sensor include infrared wavelength(0.7~3.0㎛) and radiant infrared wavelength(3.0~100㎛). Infrared(IR) wavelengths are divided into five bands: near infrared(NIR), shortwave infrared(SWIR), midwave infrared(MWIR), longwave infrared(LWIR), and far infrared(FIR). Most thermal sensors use the LWIR to capture images. Thermal sensors measure the temperature of the target in a non-contact manner, and the data can be affected by the sensor's viewing angle between the target and the sensor, the amount of atmospheric water vapor (humidity), air temperature, and ground conditions. In this study, the characteristics of three thermal imaging sensor models that are widely used for observation using unmanned aerial vehicles were evaluated, and the optimal application field was determined.

• 한국컴퓨터정보학회논문지
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• 제22권7호
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• pp.39-45
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• 2017

In this paper, we propose three compensation methods to solve problems in high-resolution airborne infrared camera and to improve long-range target information acquisition performance. First, image motion and temporal noise reduction technique which is caused by atmospheric turbulence. Second, thermal blurring image correction technique by imperfect performance of NUC(Non Uniformity Correction) or raising the internal temperature of the camera. Finally, DRC(Dynamic Range Compression) and flicker removing technique of 14bits HDR(High Dynamic Range) infrared image. Through this study, we designed techniques to improve the acquisition performance of long-range target information of high-resolution airborne infrared camera, and compared and analyzed the performance improvement result with implemented images.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권12호
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• pp.4292-4307
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• 2021

For the research field of night infrared surveillance video, the target imaging in the video is easily affected by the light due to the characteristics of the active infrared camera and the classical ViBe algorithm has some problems for moving target extraction because of background misjudgment, noise interference, ghost shadow and so on. Therefore, an improved ViBe algorithm (I-ViBe) for moving target extraction in night infrared surveillance video is proposed in this paper. Firstly, the video frames are sampled and judged by the degree of light influence, and the video frame is divided into three situations: no light change, small light change, and severe light change. Secondly, the ViBe algorithm is extracted the moving target when there is no light change. The segmentation factor of the ViBe algorithm is adaptively changed to reduce the impact of the light on the ViBe algorithm when the light change is small. The moving target is extracted using the region growing algorithm improved by the image entropy in the differential image of the current frame and the background model when the illumination changes drastically. Based on the results of the simulation, the I-ViBe algorithm proposed has better robustness to the influence of illumination. When extracting moving targets at night the I-ViBe algorithm can make target extraction more accurate and provide more effective data for further night behavior recognition and target tracking.