三通道RGB图批量转单通道灰度图

pathdir='/home/zhang/下载/SEG_task/Annotation/out_10_labeled/';%文件夹路径
format = 'png';%文件格式
Savepath = '/home/zhang/下载/SEG_task/Annotation/out_10_labeled_grey';
files=dir(strcat(pathdir,'*.',format));
steps=100;
hwait=waitbar(0,'准备开始');
for n=1:numel(files)
     filename=strcat(pathdir,files(n).name);
     img=imread(filename);
     x=rgb2gray(img);
     imwrite(x,Savepath,'png');%自动设置为替换原文件，可以修改
     str='正在运行中巴啦啦巴啦';
     waitbar(n/numel(files),hwait,str);
end
close(hwait);