清华大佬耗费三个月吐血整理的几百G的资源，免费分享！....>>>

#!/bin/bash

# yum install ImageMagick

# cd /img/dir

for file in */*.jpg; do
	to_middle_file="${file%.*}_m.${file##*.}"; //文件名加后缀 如 hello_m.jpg
	to_small_file="${file%.*}_s.${file##*.}";
	convert ${img} -resize 300x180! ${to_middle_file};
	ls ${to_middle_file};
	convert ${img} -resize 100x60! ${to_small_file};
	ls ${to_small_file};
done

# convert resize argument
# 100x200       # width = 100, height = 200
# 300x          # width = 300, height = proportional
# x300          # width = proportional, height = 300
# ! 表示强制转换大小,不加“!”会按照原图片比例压缩图片