基于FPGA的离散卡尔曼自适应图像降噪(论文13000字)
摘要:图像在作为传递信息的媒介时,会受到复杂的客观因素的影响,使得在传输或采集等过程中难免受到噪声信号的干扰,从而导致图像的像素值发生改变,降低了图像的质量。所以在接收图像后需要对图像进行降噪处理,提高图像的清晰度。本论文采用离散卡尔曼滤波算法,根据噪声信号的特性,利用时间更新方程和测量更新方程进行运算处理,对不同类型的噪声进行对比降噪。时间更新方程用当前状态下的变量及协方差估计的值来推算估计下一状态的各个参数值,测量更新方程则计算增益,并参与状态估计值的运算。通过在每一周期对各个参数进行递归运算,得到最终估计值输出,滤除噪声信号。最后将其运行与FPGA硬件平台上,依据FPGA的有并行运算特点,使程序高速运行,从而提高滤波的运行效率,同时在硬件平台上进行实现滤波降噪并输出图片。
关键词:FPGA;离散卡尔曼滤波;自适应图像去噪;数字图像处理。
Discrete Kalman adaptive image denoising based on FPGA
Abstract:As the medium of transmission of information, images are affected by complex objective factors, which make it difficult to interfere with the noise signal during transmission or acquisition, which leads to the change of image pixel value and the quality of the image. Therefore, after receiving the image, we need to de noise the image and improve the definition of the image. In this paper, the discrete Calman filter algorithm is used. According to the characteristics of the noise signal, the time updating equation and the measurement update equation are used to deal with the noise, and the noise of different types is compared and reduced. The time renewal equation estimates the values of the parameters of the next state by the values of the current state variables and the covariance estimated, and the update equation calculates the gain and participates in the operation of the state estimation. By recursive computation of each parameter in each cycle, the output of the final estimate is obtained and the noise signal is filtered out. Finally, the operation and FPGA hardware platform, according to the parallel operation characteristics of FPGA, make the program run at a high speed, thus improving the efficiency of the filtering operation, at the same time, the filter is realized and the picture is output on the hardware platform.
Key words: FPGA; discrete Kalman filtering; adaptive image denoising; digital image processing
目录
1 绪论 1
1.1 课题研究的意义及背景 1
1.2 相关技术研究现状 1
1.2.1图像算法研究现状 1
1.2.2 FPGA在图像处理方面的研究现状 1
1.3 本文主要设计内容及安排 2
2 图像去噪方法的研究 3
2.1 噪声的分类 3
2.2 基于卡尔曼滤波去噪方法 3
2.2.1卡尔曼滤波原理 3
2.2.2 离散卡尔曼滤波算法 3
2.3 图像去噪质量评价 5
2.3.1针对不同噪声类型去噪的MATLAB实现 5
2.3.2针对不同Q、R值去噪的MATLAB实现 7
3 FPGA设计介绍 10
3.1设计平台介绍 10
3.1.1 FPGA发展 10
3.1.2 FPGA原理及特点 10
3.2 FPGA开发流程 11
4卡尔曼滤波的FPGA设计 14
4.1 总体结构设计 14
4.2 图片数据输入存储模块 14
4.3 时钟分频模块 16
4.4 卡尔曼滤波模块 17
4.5 数据输出及显示模块 19
5 实验测试结果分析 20
6 总结 22
参考文献 22
致谢 24
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