透火焰红外数字全息图像的分辨率增强算法

Resolution enhancement algorithm based on infrared digital holography imaging through flame

近年来,高温干扰遮蔽情况下利用红外热成像与数字全息成像相结合的新技术观察火场中目标成为时下的研究重点。理论上火焰和浓烟对长波长的红外数字全息成像没有影响,但在现实火场环境中,燃烧物的大颗粒灰尘将会干扰光路,严重增加了全息图重建图像的噪声。本文提出了一种新的图像处理算法来抑制红外数字全息重建的噪声。该算法利用双边滤波器配合拉普拉斯金字塔算法将全息重建图像的细节和能量层分开,再对细节层进行滤波,然后用反向拉普拉斯金字塔算法将分离的层叠加回重建图像中,从而提高重建像的分辨率,并通过模拟火场环境验证了该算法对改善红外数字全息图重建像的分辨率具有显著效果。

In recent years, the use of new technologies combining infrared thermal imaging and digital holographic imaging to observe the targets in the fire field has become a current research focus. In theory, flame and smoke have no effect on long-wavelength infrared digital holography, but in the real fire environment, large particles of dust from the combustion will interfere with the light path, seriously increasing the reconstruction noise of the hologram. This paper proposes a new image processing algorithm to suppress the noise of infrared digital holographic reconstruction. The algorithm uses a bilateral filter combined with the Laplacian pyramid algorithm to separate the details and energy layers of the holographic reconstructed image, filters the detail layer, and then superimposes the separated layers back into the reconstructed image by the inverse Laplacian pyramid algorithm. Therefore, the resolution of the reconstructed image is improved, and the simulation of the fire field environment proves that the algorithm has a significant effect on improving the resolution of the reconstructed image of the infrared digital hologram.