gif are wrongly converted to jpg

[Andrekra]

My use case involves using animated gifs. When a format is specified in show_alchemy_picture_path, it tries to converted the gif to an jpg. When dragonfly calls the 'convert' method on a gif to a jpg, it generates 1 jpg per frame, causing a massive slowdown and in the end the picture is not shown (not sure why now, maybe because the filename is different now, appended with the frame number).

The correct call would be convert 'images.gif[0]' image.png or convert -flatten images.gif image.png

The thumbnails in the admin, are stripped of their extension in

alchemy_cms/app/helpers/alchemy/admin/essences_helper.rb

Line 74 in 0f90048

name: content.ingredient.urlname,

So it always uses the default format of png defined in routes. This would fix it:

image_tag(
        alchemy.thumbnail_path({
          id: content.ingredient.id,
          name: content.ingredient.urlname,
          sh: content.ingredient.security_token(image_options),
          format: content.ingredient.try(:image_file).try(:ext) || configuration(:image_output_format)
        }.merge(image_options)),
        alt: content.ingredient.name,
        class: 'img_paddingtop',
        title: _t(:image_name) + ": #{content.ingredient.name}"
      )

But this happens in various places, and not every view uses this helper

• alchemy_cms/app/views/alchemy/admin/pictures/_picture_to_assign.html.erb

  Line 11 in 81dbe18

  alchemy.thumbnail_path(

• alchemy_cms/app/views/alchemy/admin/pictures/_picture.html.erb

  Line 70 in 81dbe18

  alchemy.thumbnail_path(id: picture, size: @size, sh: picture.security_token(size: @size)),

To fix generating multiple frames, I hooked into the alchemy/pictures_controller.rb#send_image method

 def send_image(image, format)
      request.session_options[:skip] = true
      ALLOWED_IMAGE_TYPES.each do |type|
        format.send(type) do
          options = []
          if type == 'jpeg'
            quality = params[:quality] || Config.get(:output_image_jpg_quality)
            options << "-quality #{quality}"
          end
          # Flatten gif sequence when converting to a different type
          if type != "gif" && image.ext == 'gif'
            options << "-flatten"
          end

          render text: image.encode(type, options.join(' ')).data
        end
      end
    end

[tvdeyen]

Confirm that displaying animated gifs are broken. Will provide a pull request that fixes that in the way that all thumbnails will get converted correctly into the target format.

But, I will not change the thumbnail format, because one does not want to really see the animation inside the thumbnail.

This would be visually distracting. The zoomed image in the library overlay should display the image in original format, so one can preview the animation if they prefer.

Thanks for your pictures controller fix, I will use that in my PR.