An Adaptive Global and Local Tone Mapping Algorithm Implemented on FPGA
An Adaptive Global and Local Tone Mapping Algorithm Implemented on FPGA
复制标题
FPGA 上实现的自适应全局和局部色调映射算法
DOI：
10.1109/tcsvt.2019.2931510
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发表时间：
2020
影响因子：
8.4
通讯作者：
and Tetsuya Asai
中科院分区：
文献类型：
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作者：
Prasoon Ambalathankandy;Masayuki Ikebe;Takashi Yoshida;Takeshi Shimada;Shinya Takamaeda-Yamazaki;Masato Motomura;and Tetsuya Asai
提出了一种快速全局和局部自适应色调映射算法及其现场可编程门阵列(FPGA)实现。特别设计的色调映射函数基于局部直方图均衡，分别控制全局和局部特征。与其他色调映射算子相比，该算法将明暗晕分开管理，并且单独使用局部色调映射函数，可以有效地抑制噪声。通过主观评价和客观评价，验证了算法的有效性。在保持较高精度的前提下，利用平均直方图，以较少的直方图实现快速平滑的局部直方图估计。我们的新实现方法需要最少的数据访问和更少的内存，因为它是在240×135像素的缩小帧尺寸下运行的。相对局域大小为248×248@全高清分辨率(1920×1080)。对于低延迟像素输出，系统使用前一帧的像素信息执行色调映射。当我们在FPGA(TB-7K-325TIMG和Xilinx KINTEX-7)上实现该系统时，我们实现了轻量级的硬件，因为总使用率约为可用FPGA资源的25%。使用我们演示的在线1080p视频，使用我们的硬件色调映射系统进行实时视频处理。
We present a fast global and locally adaptive tone mapping algorithm and its field-programmable gate array (FPGA) implementation. The specially designed tone mapping function, which is based on local histogram equalization, controls global, and local characteristics individually. In contrast to other tonemap operators, our algorithm manages light/dark halos separately and by using local tonemap function alone, it can effectively suppress noise. We validated the effectiveness of our algorithms using subjective and objective assessment. Using an average of the bins, we achieve fast smoothed local histogram estimation with fewer bins while maintaining high accuracy. Our new implementation method requires minimal data access and reduced memory as it operates with a downscaled frame size of 240 × 135 pixels. Relative local area size is 248 × 248 @Full-HD resolution (1920 × 1080). For low-latency pixel output, the system performs the tone mapping using pixel information from the previous frame. When we implemented the system on FPGA (TB-7K-325TIMG and Xilinx Kintex-7), we achieved lightweight hardware as the total usage rate is about 25% of the available FPGA resource. Using an online 1080p video we demonstrate, a real-time video processing using our hardware tone mapping system.