Syntax to support arbitrary attributes for filters

I've extended the filter syntax to support arbitrary attributes that get passed to the filter method as a hash of options. An example of the syntax:

    {{ images['picture.gif'] | img_tag: size: '410x51', border: 0, alt: 'My Picture' }}

and a possible implementation of the img_tag filter:

    module TagFilters
      include ActionView::Helpers::TagHelper

      def img_tag(file, options = {})
        options.symbolize_keys!
        options[:src] = file.public_path
        if options[:size]
          options[:width], options[:height] = options[:size].split("x") if options[:size] =~ %r{^\d+x\d+$}
          options.delete(:size)
        else
          options[:width] = file.width
          options[:height] = file.height
        end
        tag 'img', options
      end
    end