ImageMagick无编码委托

我以前可以使用ImageMagick将文本转换为图像,但现在我收到了以下错误消息:

$ echo text | convert -background none text:- file
convert: no encode delegate for this image format `TEXT' @ error/constitute.c/WriteImage/1167.

ImageMagick是使用自制软件安装的

imagemagick: stable 7.0.7-10 (bottled), HEAD
Tools and libraries to manipulate images in many formats
https://www.imagemagick.org/
/usr/local/Cellar/imagemagick/7.0.7-10 (1,523 files, 23.1MB) *
  Poured from bottle on 2017-11-10 at 15:46:33
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/imagemagick.rb