# File\_column, RMagick, and watermarking **URL:** \ **Category:** Rails\ **Created:** [February 28, 2006, 8:57pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941 "2006-02-28T20:57:20Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [February 28, 2006, 8:57pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/1 "2006-02-28T20:57:20Z")
I’m working on a photo gallery and I’m using File\_column to handle the uploads of the files and create my thumbnails, but does anyone here have any idea how to have a watermark (opaque text maybe) placed over one of the versions? Any ideas on how to go about this would be great. Even if it’s just straight RMagick code, that would be fine too. Thanks in advance for the help! Brian H. Web D. Learning & Technology Services Schofield 3-B University of Wisconsin-Eau Claire 715 836 3585 removed\_email\_address@domain.invalid ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 8:51am UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/2 "2006-10-26T08:51:31Z")
I have a similar requirement; did you find any solution for this? thanks Hogan, Brian P. wrote: > I’m working on a photo gallery and I’m using File\_column to handle the > uploads of the files and create my thumbnails, but does anyone here have > any idea how to have a watermark (opaque text maybe) placed over one of > the versions? Any ideas on how to go about this would be great. Even if > it’s just straight RMagick code, that would be fine too. > > Thanks in advance for the help! > > Brian H. > Web D. > Learning & Technology Services > Schofield 3-B > University of Wisconsin-Eau Claire > 715 836 3585 > removed\_email\_address@domain.invalid ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 9:36pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/3 "2006-10-26T21:36:40Z")
Hogan, Brian P. wrote: > I’m working on a photo gallery and I’m using File\_column to handle the > uploads of the files and create my thumbnails, but does anyone here have > any idea how to have a watermark (opaque text maybe) placed over one of > the versions? Any ideas on how to go about this would be great. Even if > it’s just straight RMagick code, that would be fine too. > > Thanks in advance for the help! There are many ways to write text on an image with RMagick. The simplest way is to use the Draw#text method: [RMagick 1.15.0: class Draw](http://www.simplesystems.org/RMagick/doc/draw.html#text). Also check out the example for the Image#watermark method: [RMagick 1.15.0: class Image (instance methods, part 3)](http://www.simplesystems.org/RMagick/doc/image3.html#watermark) and the example for the Image#mask attribute: [RMagick 1.15.0: class Image (attribute methods)](http://www.simplesystems.org/RMagick/doc/imageattrs.html#mask). These last two require that you have RMagick 1.14.0 or later. ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 10:24pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/4 "2006-10-26T22:24:47Z")
FlexImage seems great, but i would prefer to story my images on disk rather than in the DB… thats not possible with FlexImage, is it? ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 9:50pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/5 "2006-10-26T21:50:07Z")
Hogan, Brian P. wrote: > I’m working on a photo gallery and I’m using File\_column to handle the > uploads of the files and create my thumbnails, but does anyone here have > any idea how to have a watermark (opaque text maybe) placed over one of > the versions? Any ideas on how to go about this would be great. Even if > it’s just straight RMagick code, that would be fine too. > > Thanks in advance for the help! > > Brian H. > Web D. > Learning & Technology Services > Schofield 3-B > University of Wisconsin-Eau Claire > 715 836 3585 > removed\_email\_address@domain.invalid I’ve just released an updated to the FlexImage that makes it super easy to do just that. Simply provide a PNG and give it some basic info on how to size and place it. Check it out. [http://beautifulpixel.com/articles/2006/10/26/flex-image-now-has-special-effects](http://beautifulpixel.com/articles/2006/10/26/flex-image-now-has-special-effects) ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 11:11pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/6 "2006-10-26T23:11:46Z")
Thorsten L wrote: > FlexImage seems great, but i would prefer to story my images on disk > rather than in the DB… thats not possible with FlexImage, is it? Not currently, sorry ☹ At the very least you can take a look into the source and see the rmagick commands that do the overlay. Check out FlexImage::Model#overlay! for the implementation. ---
**Author:** ![HoganS\_Brian\_P](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/9de0a6/32.png) [@HoganS\_Brian\_P](https://www.ruby-forum.com/u/HoganS_Brian_P)\ **Post date:** [October 26, 2006, 11:24pm UTC](https://www.ruby-forum.com/t/file-column-rmagick-and-watermarking/74941/7 "2006-10-26T23:24:56Z")
I totally forgot I posted this. I figured it out with RMagick a long time ago… it’s pretty simple actually This places “sample” diagonally across the middle of the image. You needa graphic called ‘sample.png’ that contains some alpha transparency but that’s easy to create. class Photo \< ActiveRecord::Base ``` file_column :filename, :magick => { :versions => { "thumb" => "50x50", "large" => "320x240>" } } validates_presence_of :filename, :description before_create :watermark_image private def watermark_image require 'RMagick' # probably don't need this line but it's here ``` anyway dst = Magick::Image.read(self.filename).first src = Magick::Image.read("#{RAILS\_ROOT}/config/sample.png").first result = dst.composite(src, Magick::CenterGravity, Magick::OverCompositeOp) result.write(self.filename) ``` end ``` end