A new watermarking detecting algorithm which resists geometric distortion is proposed, based on Fourier-Mellin transform and phase correlation features.
基于傅里叶-梅林变换特性和相位相关性，提出了一种新的抗几何失真数字水印算法。
2
With the correlation technique, direction and speed of the infrasound can be calculated by computing the time delay of each detector and by using geometric knowledge.
利用互相关技术，计算信号在不同传感器上的时间延迟，再由平面几何原理，得到波的方位和波速。
3
Phase correlation algorithm as a kind of image matching method has many advantages such as insensitive to noise, unrelated to illumination of target, immune to geometric distortion.