ImageMagic批处理多个图片的一些方法技巧

比如说，我想将一个目录下的所有图片都换个名字，或者都从png格式转换成jpg格式，这个时候需要批处理，可以使用 mogrify 命令，但可以使用传统的 convert 命令配合shell命令也可以实现，很容易理解。

  # Use a simple shell loop, to process each of the images.
  mkdir thumbnails
  for f in *.jpg
  do   convert $f -thumbnail 200x90 thumbnails/$f.gif
  done

  # Use find to substitute filenames into a 'convert' command.
  # This also provides the ability to recurse though directories by removing
  # the -prune option, as well as doing other file checks (like image type,
  # or the disk space used by an image).
  find * -prune -name '*.jpg' \
         -exec  convert '{}' -thumbnail 200x90 thumbnails/'{}'.gif \;

  # Use xargs -- with a shell wrapper to put the argument into a variable
  # This can be combined with either "find" or "ls" to list filenames.
  ls *.jpg | xargs -n1 sh -c 'convert $0 -thumbnail 200x90 thumbnails/$0.gif'

  # An alternative method on linux (rather than plain unix)
  # This does not need a shell to handle the argument.
  ls *.jpg | xargs -r -I FILE   convert FILE -thumbnail 200x90 FILE_thumb.gif