freetype依赖于libpng，libpng又依赖于zlib。所以先编译安装zlib，再编译安装libpng，最后编译安装freetype。问题一：zlib安装时需要使用交叉编译器跟着正点原子的应用开发手册安装zlib，直接参照手册上执行./configure,make,makeinstall后安装编译libpng时会报错，说找不到zli

 001、问题，安装devtools中遇到如下报错：Configurationfailedtofindoneoffreetype2libpnglibtiff-4libjpeg. 002、解决方法：[root@pc1~]#yuminstallfreetype-devellibpng-devellibtiff-devellibjpeg-devel##根据提示安装  。 

libharu编译需要libpng，libpng依赖zlib，所以需要下载这三个库libharu下载：http://libharu.org/libpng下载：http://www.libpng.org/pub/png/libpng.htmlzlib下载：https://www.zlib.net/ *：libpng我下载的版本是V1.6.40，对应的zlib版本需要在V1.0.4以上，我用的zlibV1.3参考链接：ht

libpnglibpngistheofficialPNGreferencelibrary.ItsupportsalmostallPNGfeatures,isextensible,andhasbeenextensivelytestedforover28years.Thehomesitefordevelopmentversions(i.e.,maybebuggyorsubjecttochangeorincludeexperimen

参考链接：https://blog.csdn.net/qq_37924224/article/details/119181028?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522168776812116782427434491%2522%252C%2522scm%2522%253A%252220140713.130102334..%2522%257D&request_id=168776812116782427434491&b

一，dwebp/cwebp缺少libpng库时的报错:[root@localhostwork]#dwebpa.webp-oa.pngDecodeda.webp.Dimensions:856x300.Format:lossy.Nowsaving...PNGsupportnotcompiled.Pleaseinstallthelibpngdevelopmentpackagebeforebuilding.Youcanrunwith

小图片： IfranView:   IrfanView是免费软件但不开源。下面的程序读入small.png，用最简单的方法放大，然后写入big.png:/*https://www.nongnu.org/pngpp/在libpng上包

 ​​https://stackoverflow.com/questions/22745076/libpng-warning-iccp-known-incorrect-srgb-profile​​ 报错原因： Libpng-1.6检查ICC配置要比之前版本严格。解决

所需资源：gitclonehttps://git.videolan.org/git/x264.githttps://libav.org/  -------------官方库文件wgethttps://libav.org/releases/libav-12.3.tar.gzwgetht