我在研究PPG信号。我想检测出一些点来进行特征提取。但是,我无法在我自己的数据集中检测到下图所示的点:
我尝试使用fft作为以下代码:
clear
clc
close all
%% Data Importation and Extraction
load('testdata.mat');
increment = 1;
x = [1:increment:length(PPG)];
d = deriv2(PPG);
%%
subplot 211
plot(x,PPG);xlim([0 100]);grid on
subplot 212
plot(diff(diff(P
我尝试使用从下载的cxcorr_fft在两个图像之间执行循环交叉相关。
function [ h ] = cxcorr_fft( a,b )
%CXCORR_FFT Calculates the circular crosscorrelation of the two input
% vectors using the fft based method
%
% Author: Johannes Schmitz, Oct. 16, 2013
% schmitz@ti.rwth-aachen.de
% zeropad to the same length M
if (len