matlab 批量更改文件夹下的图片格式

clc
clear
path1='D:\格式转换\CMU_car_testing_images\car_images3\*.pgm';
dir1=dir(path1); 
path_new='D:\格式转换\CMU_car_testing_images\car_images3\';
for i=1:length(dir1)
    filename=dir1(i).name;
    I=imread([path_new,filename]);
    filename=strcat('C:\car_images3\',filename);
    filename_new=strcat(filename(1:end-4),'.bmp');
    imwrite(I,filename_new,'bmp');
end

文件名不变 pgm后缀改为bmp