基于FPGA的红外图像清晰化系统设计

Design of infrared image cleared system based on FPGA

针对红外图像普遍存在细节模糊、对比度低的问题,设计实现了基于FPGA的红外图像清晰化系统。首先对输入原始红外图像进行8×8窗口的平滑滤波,然后将滤波后的图像叠加拉普拉斯算子进行细节增强,以解决传统拉普拉斯增强产生的噪声放大问题。最后通过Gamma校正曲线调整增强后图像的灰度。硬件系统实现时采用串并行流水计算方式,仅占用2%的Slice Register和5%的LUT资源,工作频率最高达228 MHz,满足实时处理视频图像的需求。实验结果表明,系统能够有效提高图像的对比度,增强目标景物的细节。

In order to solve the problem of blurred details and low contrast between the target and the background in infrared images,an infrared image clearing system based on FPGA was designed and implemented.The input original infrared image was smoothed with 8×8 windows,and then the filtered image was enhanced by Laplacian operator,thereby avoiding the noise amplification caused by traditional Laplacian enhancement.Moreover,the grayscale of enhanced image was adjusted through the Gamma correction curve.The serial and parallel pipeline calculation method was adopted in infrared image clearing hardware system;so that,the hardware system could work with an estimated frequency of 228 MHz by occupying only 2%of slice register and 5%of LUT resources,which can meet the requirements of real-time application of video images.The results verified that the system could effectively improve the contrast of the image and enhance the target details.