基于 DSP+FPGA 的红外热成像伪彩色变换系统*
摘 要:提出了一种基于数字信号处理器(DSP)和可编程逻辑门阵列(FPGA)双芯片架构的红外热成像伪彩色变换系统,可
应用于高速图像采集和数据处理,该技术在石油化工、冶金、电力、军事侦查等行业应用十分有效,是一种新兴的非接触
式诊断技术。该系统采用双处理器流水线体系结构,FPGA 首先从红外探测器中采集出来的一帧 Raw 格式的原始灰度温度
图像,传送到 DM642 运行核心处理算法,计算出三段式分割参数,传回 FPGA 修正原始灰度温度图像,再按一定的格式
打包传给 DM642 进行基于通道的灰度到彩色线性插值算法变换,转换为 24 位 RGB 格式图像,最终通过以太网口传到上
位机显示图像和后序处理。实验结果表明:该系统处理一幅大小为 320x240 像素的原始图像的时间约为 15ms,相比单
芯片处理系统, 双芯片处理架构使系统处理数据的实时性得到了提高, 缩短了系统开发周期。
关键词: DSP;FPGA;红外探测器;双线性插值
中文分类号:TP338.6 文献标志码:A 文章编号:
A Study on Pseudo Color Transformation System
Controlled by DSP and FPGA in Infrared Thermal Imaging
Abstract : Here, a pseudo color transformation is presented. It was applied in an infrared thermal imaging system controlled by
dual-processor pipeline architecture of digital signal processor (DSP) and field programmable gate array (FPGA), in order to improve
the speed of image acquisition and data processing in real-time. This technology is a modern non-contact diagnostic technique, which
is widely available in petroleum chemical industry, metallurgy, electric power, military reconnaissance, etc. Double chips work
coordinately and effectively. Firstly, the FPGA collected a raw format of the original gray image from an infrared detector, and then
sent it to the DM642 to execute the core processing algorithm. After calculating three-segment pretreatment parameters, it returned
back to the FPGA for data pre-processing to recover the lost pixels. In FPGA, a certain format was packaged and passed to the
DM642, where the algorithm of bilinear interpolation converted the gray format image to color one, termed as RGB format image,
and ultimately the RGB format image was transmitted to the host computer through the Ethernet port to display. It took 15 ms for the
system to process a raw image of 320x240 pixels. The framework of double-chip improve the speed of real-time processing
compared to single-chip system, shortening the development cycle.
Key Words: DSP, FPGA, Infrared detector, Bilinear interpolation