I am having trouble implementing a simple image uploader with Carrierwave/Minimagick gems in RoR.
I'm trying to convert the file to grayscale upon upload, but I am getting an error. Here is the code:
image_uploader.rb:
class ImageUploader < CarrierWave::Uploader::Base
include CarrierWave::MiniMagick
# Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
include Sprockets::Helpers::RailsHelper
include Sprockets::Helpers::IsolatedHelper
storage :file
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
# Process files as they are uploaded:
process :convert_to_grayscale
def convert_to_grayscale
manipulate! do |img|
img.quantize(256, Magick::GRAYColorspace)
img = yield(img) if block_given?
img
end
end
When I try to upload a file, I get the following error:
uninitialized constant ImageUploader::Magick
app/uploaders/image_uploader.rb:36:in `block in convert_to_grayscale'
app/uploaders/image_uploader.rb:35:in `convert_to_grayscale'
I believe this is due to the Magick::GRAYColorspace enum constant. Any ideas why this isnt working?
Is the manipulate function that loads images to memory? Does It return a image list?
I think that the images aren't loaded correctly. The problem isn't the Magick enum.
Here is a sample example:
require 'RMagick'
clown = Magick::ImageList.new("clown.jpg")
clown = clown.quantize(256, Magick::GRAYColorspace)
clown.write('monochrome.jpg')
Related
I am using Carrierwave to upload images and that works fine but I am now trying to use Minimagick to process these uploaded images.
What is going on?
The images still upload as well as their thumb version, however both images are exactly the same size.
Here is the uploader code:
class FileUploader < CarrierWave::Uploader::Base
include CarrierWave::MiniMagick
# Choose what kind of storage to use for this uploader:
storage :file
# Override the directory where uploaded files will be stored.
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
# Create different versions of your uploaded files:
version :thumb do
process :resize_to_fit => [100, 100]
end
# Add a white list of extensions which are allowed to be uploaded.
def extension_white_list
%w(jpg jpeg gif png)
end
end
And here is how I am calling it:
<%= image_tag example.my_file.url(:thumb).to_s %>
I dont think it is anything to do with the way I am calling it because the two files created by all this are the same, so sound slike its to do with processing it on upload.
Here is the folder created for each object:
Image
--- Fixed ---
The issue was ImageMagick. It was not properly configured on my machine so that means no gem that deals with image processing (Paperclip, Minimagick or Dragonfly) could complete any image manipulation.
I want to upload a zip file contains documents and after uploading it to server I want to extract those on server.
I have used Carrierwave Gem to upload zip file code is below for that :
class AttachmentUploader < CarrierWave::Uploader::Base
# Include RMagick or MiniMagick support:
# include CarrierWave::RMagick
# include CarrierWave::MiniMagick
# Choose what kind of storage to use for this uploader:
storage :file
# storage :fog
# Override the directory where uploaded files will be stored.
# This is a sensible default for uploaders that are meant to be mounted:
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
def extension_white_list
%w(zip)
#%w(pdf doc htm html docx)
end
end
No what I want to know that which Gem can help me to achieve the extraction part and where that code will be placed in this uploader class or anywhere else.. I'm very new to this rails stuff so if this question require anything more pls do let me know.
I am new to RoR and I'm trying to develop a slide sharing app through which users can upload and share a multipage PDFs containing a deck of slides (one slide per page). Viewers can then view these slides on a "show" page.
Behind the scenes I am trying to convert the multipage pdf into several .png files (1 pdf page -> 1.png file), and then display them in a carousel/slider fashion.
Here is my uploader:
# encoding: utf-8
class DocUploader < CarrierWave::Uploader::Base
# Include RMagick or MiniMagick support:
# include CarrierWave::RMagick
include CarrierWave::MiniMagick
# Choose what kind of storage to use for this uploader:
storage :file
# storage :fog
# Override the directory where uploaded files will be stored.
# This is a sensible default for uploaders that are meant to be mounted:
def store_dir
# 'public/doc_uploads/'
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
process :filename
process :generate_png
def generate_png
pdf = MiniMagick::Image.new(self.file.path)
pdf.pages.each_with_index do |page, index|
page.write("page#{index}.png")
end
end
# Add a white list of extensions which are allowed to be uploaded.
# For images you might use something like this:
def extension_white_list
%w(pdf)
end
# Override the filename of the uploaded files:
# Avoid using model.id or version_name here, see uploader/store.rb for details.
def filename
'doc.pdf' if original_filename
end
end
When I try to upload a multipage pdf document, it throws me this error:
'identify /public/uploads/tmp/1443619784-406-3861/doc.pdf' failed with error: at the line pdf.pages.each_with_index do |page, index|
I have tried different solutions to converting the document, but none of them have worked for me so far. Why would a run of the mill .pdf file fail minimagick's validation? Is there anything I can do to avoid running into this issue? Any advice will be greatly appreciated!
I have successfully implemented image uploading using carrierwave, fog and Amazon S3. In my imageuploader am using only fog as storage. But when i check my database i can see that just the file name is written instead of the amazon url. In my views its fetching correctly from aws without any issues.
Is it supposed to be like this?
If so how the application figure out the exact url to s3?
imageuploader.rb`
# encoding: utf-8
class ImageUploader < CarrierWave::Uploader::Base
# Include RMagick or MiniMagick support:
# include CarrierWave::RMagick
# include CarrierWave::MiniMagick
include CarrierWave::MiniMagick
#Include the sprockets-rails helper for Rails 4+ compatibility:
include Sprockets::Rails::Helper
storage :fog
version :index_size do
process :resize_to_fill => [258, 173]
end
version :thumb_size do
process :resize_to_fill => [100, 100]
end
def extension_white_list
%w(jpg jpeg gif png)
end
end
Your config has the bucket name and the database has the filename. These are the only two pieces of information that are actually required to construct a filename (and it can be done without other API calls). The urls are actually pretty regular, so it is fairly straightforward for the server to do this. Hope that helps!
I am using carrierwave_backgrounder to upload images to S3 in a background process with Sidekiq.
Here's my background_uploader.rb class...
class BackgroundUploader < CarrierWave::Uploader::Base
include ::CarrierWave::Backgrounder::Delay
include CarrierWave::RMagick
include CarrierWave::MimeTypes
process :set_content_type
# Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
include Sprockets::Helpers::RailsHelper
include Sprockets::Helpers::IsolatedHelper
storage :fog
def store_dir
"uploads/backgrounds/#{model.id}"
end
def default_url
"/assets/default.jpg"
end
process :resize_to_fit => [1024, 1024]
process :convert => 'jpg'
process :fix_exif_rotation
def extension_white_list
%w(jpg jpeg png)
end
def filename
#name ||= Digest::MD5.hexdigest(File.dirname(current_path.to_s))
"#{#name}.#{file.extension}" if original_filename
end
# Rotates the image based on the EXIF Orientation & applies gaussian blur
def fix_exif_rotation
manipulate! do |img|
img.auto_orient!
img = yield(img) if block_given?
img = img.gaussian_blur(0.0, 20.0)
img
end
end
end
carrierwave_backgrounder.rb:
CarrierWave::Backgrounder.configure do |c|
c.backend :sidekiq, queue: :carrierwave
end
background.rb contains:
mount_uploader :image, BackgroundUploader
process_in_background :image
I then run sidekiq -q carrierwave to fire up the background workers. All is working good! Upload a file, I see the queue accept it and start working...
If I immediately open up my AWS S3 Console I see the original file in there. Non-resized and un-blurred. Once the job is complete...I refresh S3 and there's the resized/blurred version. Now both images are in there, but I only want the blurred image to be there. In my view I use...
<%= image_tag(#background.image.to_s) %>
It displays the original file. If I check the checkbox to remove the file, it does so as it should (deletes the original from S3), but the blurred version stays there.
What's getting uploaded to S3...
original.jpg (immediate...I don't want this uploaded at all)
modified.jpg (after job completes)
Long story short: I don't want the original file to upload to S3.
I think your problem is the filename method, which carrierwave may rely on to find (and delete) the original file. Does the problem go away when you use a filename that doesn't change between when it's initially stored and when you process it?