CarrierWave Processing DominantColor

Adds the dominant color of an image to your database whenever you upload it with the CarrierWave gem.

Installation

Add this line to your application's Gemfile:

gem "carrierwave-processing-dominant_color"

And then execute:

$ bundle

Add the dominant color attribute

To store the color, you need an attribute on the Rails model where you attach your uploader. Call it dominant_color_{uploader}.

For example if you have the following model:

class Article
  mount_uploader :photo, PhotoUploader
end
```ruby

You need to add a `dominant_color_photo` column to the `articles` table. You
would then create a migration by executing:

```sh
$ rails g migration AddDominantColorToArticles dominant_color_photo
$ rake db:migrate

Add the processor in your uploader

In your uploader, include the module and call the processor:

class PhotoUploader < CarrierWave::Uploader::Base
  include CarrierWave::Processing::DominantColor

  process :store_dominant_color

  # …
end

If you do any resizing or if you have several versions of your uploader, add it after you have resized the smallest version so that processing goes faster. For example:

# …
version :medium do
  process resize_to_fill: [200, 200]
end

version :thumb, from_version: :medium do
  process resize_to_fill: [42, 42]
  process :store_dominant_color
end
# …

Using your dominant color

An easy way of using your dominant colors is to put them as a background to your image tags:

<%= image_tag(article.photo.url(:thumb), style: "background: #{article.dominant_color_photo}") %>

For example, on cults3d:

Contributing

1. Fork it ( https://github.com/sunny/carrierwave-processing-dominant_color/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request