mac上使用imagealpha命令对图片进行压缩批处理

 #! /bin/bash

 #BASE_DIR="/Users/jiading/Documents/basepng";
 #OUTPUT_DIR="/Users/jiading/Documents/output";
 BASE_DIR="/Users/jiading/Documents/SwordsmanApp/art/序列帧动画/实验-分段版/9_选择迷你板固定";
 OUTPUT_DIR="/Users/jiading/Documents/SwordsmanApp/art/序列帧动画/实验-分段版output最强压缩9";

 CUR_READ_DIR="";
 CUR_WRITE_DIR="";

 dopng(){

 readPng=$;
 writePng=$;
 fileName=$;
 fileName=${fileName%.*}".png";
 echo "图片: "$fileName;

 #speed  -

 sudo /Applications/ImageAlpha.app/Contents/MacOS/pngquant -f $readPng -o $writePng"/$fileName" --quality  --speed  --nofs  --posterize 

 }

 loopDir(){

 # 进入当前读取目录
 cd $;

    for file in *;
          do

 localReadDir=$;
 localWriteDir=$;

         if [ -d $file ];then
             echo $file" is a dir";

 # 进入一个目录
 CUR_WRITE_DIR=$localWriteDir"/$file"

 # 创建对应新目录
 echo "创建目录："$CUR_WRITE_DIR;
 mkdir $CUR_WRITE_DIR

 # 进入下一级遍历
 loopDir $localReadDir"/$file" $localWriteDir"/$file"

 # 下一级遍历完之后回到当前目录
 cd $;

         elif [ -f $file ];then

         dopng $localReadDir"/$file" $localWriteDir "$file"

         fi

         done

 }

 main(){

 #,删掉旧目录
 if [ -d $OUTPUT_DIR ];then
 echo "ouput目录已存在，立马删除";
 rm -rf $OUTPUT_DIR
 fi

 #,创建output跟目录
 mkdir $OUTPUT_DIR

 #,开始遍历读取
 CUR_READ_DIR=$BASE_DIR
 CUR_WRITE_DIR=$OUTPUT_DIR
 loopDir $CUR_READ_DIR $CUR_WRITE_DIR

 echo "=-=-=-压缩完成=-=-=-="
 }

 main