Real-time image enhancement based on FPGA
-
摘要: 局部直方图均衡是以全局直方图均衡化方法为基础，对图像中每个像素点所在的邻域范围求出灰度转换函数，然后仅应用在该中心点处。为了提高算法的运算速度，特别是在处理视频图像时，采取传统的DSP的设计方法在速度上很难满足需要，因此，利用FPGA实现是一个很好的选择。为使局部直方图均衡方法能够在FPGA上具体实现，从空间域的角度改进了图像灰度直方图均衡算法，并利用VHDL语言对算法进行了完全可综合的RTL级描述，最后在硬件平台上验证了结果。Abstract: Local histogram equalization is a technique commonly used in image enhancement, and it is based on global histogram equalization. In the algorithm, the gray converting function obtained in the neighborhood of one pixel is implemented at the pixel. For increasing the speed of processing, especially for the processing of video or image, it is an optimal choice to implement FPGA because DSP based technique can not meet real-time processing requirement. For the specific implementation of this algorithm on FPGA, some improvements over the traditional algorithm are made. The RTL-level description of the algorithm by VHDL language is achieved. The result was validated on hardware.
-
Keywords:
- local histogram equalization /
- image enhancement /
- FPGA /
- VHDL
-
-
［1］章毓晋.图像处理工程：上册［M］. 2版.北京:清华大学出版社,2006.
ZHANG Yu-jin. Image processing engineering:I［M］.Rev.ed. Beijing: Tsinghua University,2006.(in Chinese)
［2］COLTUC D, BOLON P, CHASSERY J-M. Exact histogram specification［J］. IEEE TIP, 2006,15(5)：1143-1152.
［3］汪志云,黄梦为,胡钋,等.基于直方图的图像增强及其MATLAB实现［J］.计算工程与科学,2006,28(2):54-56.
WANG Zhi-yun, HUANG Meng-wei, HU Bu. Image enhancement based on of histogram and MATLAB implement［J］. Computer Engineering and Science, 2006,28(2):54-56.(in Chinese with an English abstract)
［4］刘建鹏,陈卫东,钱钧.基于FPGA的实时中值滤波器设计［J］.应用光学, 2007,28(5):712-715.
LIU Jian-peng, CHEN Wei-dong, QIAN Jun. Design of real-time median filter based on FPGA［J］. Journal of Applied Optics,2007,28(5):712-715. (in Chinese with an English abstract)
［5］ARSLAN F T, GRIGORYAN A M. Method of image enhancement bysplitting-signals［J］. IEEE Acoustics, Speech, and Signal Processing,2005(4):177-180.
［6］ALSUWAILEM A M. A novel FPGA based real-time histogram equalization circuit for infrared image enhancement［J］. Active and Passive Electronic Devices,2008(3):311-321.
计量
- 文章访问数: 4403
- HTML全文浏览量: 132
- PDF下载量: 930
下载:
陕公网安备 61011302001501号 