在本地电脑上安装好没有问题，然后按照本地安装步骤在服务器安装，然后操作时报如下错误，如果解决呢

 { [Error: Command failed: convert: unable to read font `Helvetica.ttf' @ warning/annotate.c/RenderType/917.
convert: delegate library support not built-in `Helvetica.ttf' (Freetype) @ warning/annotate.c/RenderFreetype/1714.
convert: unable to read font `Helvetica.ttf' @ warning/annotate.c/RenderType/917.
convert: delegate library support not built-in `Helvetica.ttf' (Freetype) @ warning/annotate.c/RenderFreetype/1714.
convert: non-conforming drawing primitive definition `text' @ error/draw.c/DrawImage/3171.
] code: 1, signal: null }
Error: Command failed: convert: unable to read font `Helvetica.ttf' @ warning/annotate.c/RenderType/917.
convert: delegate library support not built-in `Helvetica.ttf' (Freetype) @ warning/annotate.c/RenderFreetype/1714.
convert: unable to read font `Helvetica.ttf' @ warning/annotate.c/RenderType/917.
convert: delegate library support not built-in `Helvetica.ttf' (Freetype) @ warning/annotate.c/RenderFreetype/1714.
convert: non-conforming drawing primitive definition `text' @ error/draw.c/DrawImage/3171.

    at ChildProcess._spawn.proc.on.onExit (/app/mbp/mbp_SLB/node_modules/gm/lib/command.js:297:17)
    at ChildProcess.emit (events.js:110:17)
    at maybeClose (child_process.js:1000:16)
    at Process.ChildProcess._handle.onexit (child_process.js:1072:5)

看报错好像是缺少freetype依赖，实际上我已经安装了zlib jpg libpng freetype，在编译安装完成imagemagick后，通过命令 convert -list configure 发现DELEGATES里面根本木有，libpng freetype,(这是什么情况呢，如何解决，我在本机安装一切正常，在服务器上就异常百出)