displaying pics

hey, I try to display pics (jpg) from my db but all I get is the
"white box".
The pic and all of its att look fine in the db.

It goes something like this:

in show.rhtml:
<%= image_tag(url_for(:controller => 'upload_controller', :action =>
"getpicture", :id => @picture.id)) %>

in upload.controller.rb:
  def getpicture
    @picture = Picture.find(params[:id])
                    :filename => @picture.name,
                    :type => @picture.content_type,
                    :disposition => "inline" )

somebody has any idea ?

There is a alternate way to do this..
i once did in that way..

I stored the images under the public folder and saved the path in the db
or can do like this,

While accessing u can do like
<%= link_to image_tag("#{video.path_to_thumbnail_image}"),
video_path(video) %>
where path_to_thumbnail_image is a method to display the path of the
thumbnail created from the video.

All the best.