红外热像仪视频图像实时处理器的研制

【作者】 顾东升；

【导师】 皮德富； 杨南生；

【作者基本信息】 南京理工大学 ， 物理电子学， 2002， 硕士

【摘要】 一代某型32元红外热成像系统由于探测器材料和制造工艺的问题，限制了红外图像质量的进一步提高。主要存在两个方面的问题：首先，由于红外图像的动态显示范围较宽，为保证某些超常温目标的红外图像的显示而使绝大多数常温目标的灰度值集中分布在较低的灰度级上，从而造成红外图像的视场较暗，不利于场景信息的获取。其次，热成像系统中32元探测器的特征性能参数并不完全一致，造成各个探测器之间非常严重的不均匀性现象，降低了图像的分辨率，影响了热成像系统的有效作用距离。本文在深入研究该32元红外热成像系统成像特性的基础上，提出一种可以有效改善红外图像质量、提高热成像系统性能参数的方法和实现途径：即应用一个基于DSP+FPGA高速数字信号处理系统的实时视频图像处理器，对红外热成像系统的视频图像灰度分布进行适当的均衡，使各个探测器之间的不均匀性得到有效校正。本文主要内容如下： 深入地研究了数字图像处理技术的有关基本原理和概念，并针对上述问题给出理论解决方案和相应算法。并根据上述算法，详细的分析了选择适当高速处理器件的方法及标准，介绍了一些主要器件的性能指标和相应开发环境。 完成了红外热成像系统实时视频图像处理器硬件设计及调试。文中对该系统中各个模块的功能及电路实现进行了详细的描述，并给出了相应的结构框图。 进行了红外热成像实时视频图像处理器的软件编制，一并给出了该图像处理器的部分软件流程图。本文关于红外热成像系统视频图像处理器研制工作的最终目标是设计一个可以独立工作的嵌入式实时处理系统。因而在上述的基础上，确定了适合当前技术的实时处理方案——DSP+FPGA方案。通过实践表明，该方案取得了较为满意的结果。更多还原

【Abstract】 The quality of the infrared image can’t be improved too much because of the limits of the detector’s materials and the manufacturing technology in the first generation of Infrared Image System with 32 detectors. Two main problems are existed: First, because of the wide dynamic range of the display, the gray value of the most normal objects are distributed into the lower level to assure that the infrared image of certain high temperature objects can be displayed. So the gray value of the scene’s infrared image is lower and it makes against watching normal objects from these images. On the other hand, the responsibility of the detectors is not consonant with each other, which causes the serious non-unification among the infrared detectors. The distinguishability of the image has been reduced, which will reduce the distance of the infrared system’s operation at the same time. In this paper, it gives out an effective method to improve the performance of the infrared system based on the in-depth research about the feature of the detectors: to apply a DSP+FPGA based high-speed real-time digital signal processor to equalize the image’s gray histogram and to correct the non-unification of the 32 detectors. The main content of this paper includes:Have an in-depth research in the theory of the digital image process. Based on the research mentioned above, it brings forward the scheme and the corresponding arithmetic of the real-time image process. Due to the scheme it also discusses the methods and standards how to choose the right devices used in this image process system. The main parameters and developing environments of these devices are listed, too.Design and debug the hardware of this real-time infrared image processor. In the paper, the function and the circuit design of every module in the system are discussed in detail. The diagrams of every module are also listed.Design the software of this infrared image processor. The software flow charts of every module in the processor are described in detail in the paper.The final goal to design the processor is to obtain an independent and built-in real-time infrared image processor. Based on the discussion above, the DSP+FPGA scheme, which can be implemented by the current technology, is an effective and no costly scheme. With the field practice of the infrared image processor, this scheme has achieved a satisfactory result.更多还原