PHP: Call to undefined function imageconvolution() 错误
在用PHP实现一个图片服务器时，本地服务器图片上传正常，代码上传到一台CentOS服务器后出现错误。 经调试发现是imageconvolution函数引起的PHP异常。 查php manual发现，该函数在5.1版本以上的PHP就已经引入。 服务器PHP版本是5.3.9应该不会有问题。 再查了
在用PHP实现一个图片服务器时，本地服务器图片上传正常，代码上传到一台CentOS服务器后出现错误。
经调试发现是imageconvolution函数引起的PHP异常。
查php manual发现，该函数在5.1版本以上的PHP就已经引入。
服务器PHP版本是5.3.9应该不会有问题。
再查了一下GD的版本信息，发现本地服务器和CentOS服务器中的gd库有区别。
本地是bundle版本
GD Version bundled (2.0.34 compatible)
服务是generic版本
可以判断是GD库安装问题。
远端的CentOS服务上的GD是原先就有的，不是通过PHP安装的时候一起编译安装的GD绑定版本。
解决方法是：通过使用with-gd选项重新编译安装php即可。
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