...
首页> 外文期刊>Journal of the American Helicopter Society >Brownout Cloud Characterization Using the Modulation Transfer Function
【24h】

Brownout Cloud Characterization Using the Modulation Transfer Function

机译:使用调制传递函数的欠压云表征

获取原文
获取原文并翻译 | 示例
           

摘要

The paper describes how to extract the modulation transfer function (MTF) of a brownout cloud from video recordings of specific optical patterns. The MTF is a measure of the loss of contrast and resolution caused by the cloud and can be used as the basis for a quantitative metric of brownout severity. The application of two MTF calculation methods to actual flight test data is described. One requires the use of specially designed targets, such as a Siemens star, the other relies on simple dark/light visual edges. The results show that MTF extraction can be successfully performed with a standard consumer-level video equipment and appropriate postprocessing. Also, MTF extraction can be automated using suitable image-processing techniques. The results rigorously quantify the intuitively known facts that the visual degradation caused by brownout is a space- and time-dependent phenomenon and that high spatial frequency features, i.e., fine-grained detail, are obscured before low spatial frequency features, i.e., large objects.
机译:本文介绍了如何从特定光学图案的视频记录中提取掉电云的调制传递函数(MTF)。 MTF是衡量由于云造成的对比度和分辨率损失的量度,并且可以用作掉电严重程度定量指标的基础。描述了两种MTF计算方法在实际飞行测试数据中的应用。一种要求使用特殊设计的目标,例如西门子星,另一种则依靠简单的暗/亮视觉边缘。结果表明,使用标准的消费级视频设备和适当的后处理可以成功执行MTF提取。同样,可以使用合适的图像处理技术来自动提取MTF。结果严格量化了直觉上已知的事实,即由电压不足引起的视觉退化是一种与时间和空间有关的现象,并且在低空间频率特征(例如大物体)之前,高空间频率特征(即细粒度的细节)被遮盖了。

著录项

  • 来源
    《Journal of the American Helicopter Society》 |2013年第1期|012001.1-012001.13|共13页
  • 作者

    John Tritschler; Roberto Celi;

  • 作者单位

    Department of Aerospace Engineering, Glenn L. Martin Institute of Technology University of Maryland, College Park, Maryland;

    Department of Aerospace Engineering, Glenn L. Martin Institute of Technology University of Maryland, College Park, Maryland;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号