使用 wicked_pdf gem 和 wkhtmltopdf 在 PDF 上显示图像标题

我的控制器：

  def show
    respond_to do |format|
    format.pdf do
    #render :pdf => "show",:template => "welcome/show",:footer => { :right => 'Page [page] of [topage]' })
    #render :pdf => "show",:template => "welcome/show", :header => {:content => render_to_string({:template => 'welcome/pdf_header.html.erb'})}, :footer=> { :right => 'Page [page] of [topage]' },:margin => { :top => 38, :bottom => 35}
    #render :pdf => "show",:handlers => [:html],:template => "welcome/show.pdf.erb", :header => {:content => render_to_string({:layout => 'pdf_header.html.erb'})}, :footer=> { :right => 'Page [page] of [topage]' },:margin => { :top => 38, :bottom => 35}
    render :pdf => "show",:template => "welcome/show.pdf.erb", :header => {:content => ActionController::Base.new().render_to_string({:template => 'welcome/pdf_header.html.erb', :layout => false})}, :footer=> { :right => 'Page [page] of [topage]' },:margin => { :top => 38, :bottom => 35}
    end 
  end
end

我正在获取 PDF 以及页码，但无法获取图像标题。

这是布局：

pdf_header.html.erb

<%= image_tag  "gla/image.jpg" ,:width => "90",  :height=>"85" %>
<%#= wicked_pdf_image_tag  "gla/image.jpg" %>

一旦我将 pdf_header 作为 HTML 文件打开，我就会显示图像，但是一旦我调用 PDF，我就无法显示图像

在控制台中我得到这个

Started GET "/welcome/show.pdf" for 127.0.0.1 at 2014-04-17 09:47:05 +0530
  Processing by WelcomeController#show as PDF
Rendered welcome/pdf_header.html.erb (0.4ms)
***************WICKED***************
Rendered welcome/show.pdf.erb (0.7ms)
Rendered text template (0.0ms)
Sent data show.pdf (1.8ms)
Completed 200 OK in 782ms (Views: 1.3ms | ActiveRecord: 0.0ms)

评论的东西是我尝试过但没有成功的。有没有另一种方法可以通过给出图像的路径而不是通过 html 传递它来直接在标题中显示图像？

Acc. to 官方文档 https://github.com/mileszs/wicked_pdf#usage-conditions---important

<%= wicked_pdf_image_tag 'path' %> instead of <%= image_tag 'path' %>

这一定适合你

<%= wicked_pdf_image_tag  "gla/image.jpg" ,:width => "90",  :height=>"85" %>