Rails + Carrierwave + RMagick : Crop only if image is large

Question

I am using carrier-wave to upload images. On upload I am creating thumbnails for the image which is done using Rmagick method, resize_to_fill like below.

version :thumb do
    process :resize_to_fill=> [150, 150]
end

Here is output of all the RMagick methods carrierwave supports (none of which I want):

1. :resize_to_fill => [150,150]

This works fine on larger images but my smaller images are enlarged to 150 x 150.

2. :resize_to_fit => [150,150]

Again it was resized, I want it left alone!

3. :resize_to_limit => [150,150]

This one leaves it as is, but larger images are not cropped. They are resized to keep the aspect ratio.

Here is the result I want and how my small and larger images should look.

How do this? I want smaller images to be left alone and crop only larger images to 150 x 150. Is there another method or options I can pass to resize_to_fill?

Answer 1

I solved it by modifying :resize_to_fill carrierwave method as described in their code here.

I just made a new method with the same code with a check to see if the uploaded image is smaller. Here is the new method:

def resize_to_fill_modfied(width, height, gravity=::Magick::CenterGravity)
      manipulate! do |img|
        img.crop_resized!(width, height, gravity) unless (img.columns <= width && img.rows <= height)
        img = yield(img) if block_given?
        img
      end
    end

Does exactly what I want now.