Matlab saves every frame of video

clc;
close all;
clear all;

obj = VideoReader('E:\示例图像\扭曲帧\mat文件\expdata_large.avi');%输入视频位置
numFrames = obj.NumberOfFrames;% 帧的总数
for k = 1:numFrames
    frame = read(obj,k);
    nz = num2str(k);
    id=sprintf(nz,k);
    imwrite(frame,strcat('C:\Users\123\Desktop\技术路线\2\',id,'.jpg'),'jpg');% 保存帧
end