#182 Cropping Images (revised)

(rails >= 3.1.1) When precompiling assets, shouldn't rails include both hashed and non-hashed version of the images?

I prefer Dragonfly, but I really like how you approached this. Great timing too!

Hi Ryan!

Great Episode!

Is there any possibility you could make an episode on jCrop with Paperclip?

Having issues with minimagick. Instead of

img.crop!(x, y, w, h)

I had to do:

img.crop "#{model.crop_x}x#{model.crop_y}+#{model.crop_w}+#{model.crop_h}"
img

But the thumb version of the image is not displaying properly.

Hey, Great tutorial, but I'm running into an issue. Firstly RMagick didn't work for me. For some reason, every time without fail, it brought down my rails server when the method that does resizing was called. I found a bunch of people with the same issue, but none of the fixes, which generally included reinstalling both RMagick and Imagemagick, worked for me. The solution that got me a step further was switching to MiniMagick. Now images resize and are saved, but the next step is moving on to the actual cropping, this is now where I'm up against a new issue.

This was taken from my pdf_uploader.rb (despite the name PDF I'm currently only using jpegs just to avoid any potential difficulties there). This is my crop method, which looks pretty similar to the one in the tutorial. Someone on stack overflow also had an issue with the way your crop method worked and suggested I try something more like this:

  def crop
    if model.crop_x.present?
        img = MiniMagick::Image.open(model.pdf.path)
        x = model.crop_x.to_i
        y = model.crop_y.to_i
        w = model.crop_w.to_i
        h = model.crop_h.to_i
        img.crop(x, y, w, h)
        img
    end
  end

This doesn't work for me either even though I'm trying to explicitly edit the file. The reason has everything to do with "model.pdf.path" which I was told should do the trick... When I inspect "model.pdf.path" it prints out a tmp directory, rather than the path to where the file actually lives... This results in a big fat show stopping error, and no crop.

Errno::ENOENT in PiecesController#update

No such file or directory - /var/folders/dF/dFNM2+Y7FVScn4+OxVHKOU+++TI/-Tmp-/mini_magick20111208-45803-1027dqf.png
Rails.root: /Users/cory/Documents/Projects/TickiWiki

Application Trace | Framework Trace | Full Trace
app/uploaders/pdf_uploader.rb:78:in crop'
app/models/piece.rb:27:incrop_pdf'
app/controllers/pieces_controller.rb:107:in block in update'
app/controllers/pieces_controller.rb:106:inupdate'
Request

Parameters:

{"utf8"=>"✓",
"_method"=>"put",
"authenticity_token"=>"4+QAJEMjn1YhG+7khKbTC/SxfSeKzONoSxTd+MoQNyM=",
"piece"=>{"crop_x"=>"10",
"crop_y"=>"371",
"crop_w"=>"476",
"crop_h"=>"307"},
"commit"=>"Crop",
"id"=>"240"}

This leads me to a few questions:
1. Why, what did I do to deserve this?
2. How can I get the correct value?
3. Will the correct value even make it work?
4. Is there a better way to do this?
5. Why can't I code as quickly and with as few mistakes as Ryan Bates in a RailsCast?

Anyway, this n00b would love any suggestions anyone has. Thanks!

It's awesome! Thanks a lot. I'm using your solution in my new project.

Thank you Ryan for this episode. Has anyone used jcrop and carrierwave to mimic how Facbook's does thumbnail . That would be a cool episode maybe a revision of this cast. ;)

Good episode!

Do you think you could explain how this might work with nested objects. My images belong to a subsidiary object and I can't figure out how to crop them.

Can you help?

Another brilliant episode - thanks Ryan!

great episode as always. Thank you!

I need some advice from you. Your example works great if all versions of the uploaded image have equal widths and heights (i.e. width == height). In many cases, photos have different width and height, e.g. 640x480. And sometimes it needs to be rotated, so that width is 480px and height is 640px. If I want to have a "normal" version with dimensions 640x480 if picture is landscape and 480x640 if it is a portrait; with another "thumb" version 180x135 landscape and 135x180 portrait. Could you give some advice on how to achieve that?

I get the following error when trying to implement this tutorial. I wanted to get this work and then alter to my needs so I have not made any modifications to the original code. Any one have any suggestions? I would really appreciate the help. Thanks!

undefined method `crop_x' for #User:0x007ff7594cb2f8

Rails.root: /Users/thomasbush/Rails/college
Application Trace | Framework Trace | Full Trace

app/uploaders/avatar_uploader.rb:47:in crop'
app/controllers/users_controller.rb:43:inupdate'

Also not sure if this matters but my users system is set up with Devise, I handle roles and permissions with CanCan and I followed the #253 tutorial to get the basic carrierwave uploading working. All of course thanks to Ryan - railscasts is too good! Thanks.

Alright so I have finally solved this issue with help from stackoverflow. The issue is a conflict when combining jcrop with twitter bootstrap. The solution to my question is linked here. Its embarrassingly simple, apparently TBS sets image max width property to 100% and you simply override with with a style you create to remove this property. I was so focused on jcrop itself that I did ponder anything else causing the problem. Lesson learned, but I figured I would post for anyone elses benefit.

I was unable to get the crop working using RMagick, so I investigated what would be the equivalent using MiniMagick.

Based on this discussion on stackoverflow, I was able to come up with this working solution. This method would be saved in the User model and there is no longer a crop method within the AvatarUploader CarrierWave object.

There is one minor issue with this code, which is that the large version of the image becomes the master copy of that image. If you do not care about keeping the high resolution version of an uploaded image, this issue will not matter to you.

class User < ActiveRecord::Base
  mount_uploader :image, ImageUploader
  
  attr_accessor :crop_x, :crop_y, :crop_w, :crop_h
  after_update :crop_image

  def crop_image
    if crop_x.present?
      mini_magick = MiniMagick::Image.open(self.image.large.path)
      crop_params = "#{crop_w}x#{crop_h}+#{crop_x}+#{crop_y}"
      mini_magick.crop(crop_params)
      mini_magick.write(self.image.path)
      image.recreate_versions!
    end
  end
end

If you use a random filename for your photos, recreate_versions! won't save them to the model properly. See this: https://github.com/jnicklas/carrierwave/wiki/How-to%3A-Create-random-and-unique-filenames-for-all-versioned-files (specifically search for "recreate")

For those of you having problems with mini_magic, this worked for me:

  def crop
    if model.crop_x.present?
      resize_to_limit(600, 600)
      manipulate! do |img|
        x = model.crop_x
        y = model.crop_y
        w = model.crop_w
        h = model.crop_h
        img.crop "#{w}x#{h}+#{x}+#{y}"
        img
      end
    end
  end

When I selecting the are to crop, the selected area always be zoomed a bit. How can I fix this? I don't want the zoom effect.

render :crop brings me up to a BLANK PAGE,
“406 not acceptable” error

I have to wrap this in a format.html{}

        if params[:location][:main_image].present?
          format.html {render :crop}
        else
          format.html { redirect_to @location, notice: 'Location was successfully created.' }
          format.json { render json: @location, status: :created, location: @location }
        end

Not sure why... but it works

Hi there,

can someone offer this tutorial as a "non-square-thumbnail" example?

I ran into render issues when I try to change the parameters to a "rectangle" in the js.coffee file

After I setting enviorment from Development to Production, the jCrop seems not working correctly. It maybe the problem caused by precompiling and compressing. Any suggestions? Thx!

Hello,

I am fresher with ROR so i am trying to crop a picture but i get this error in cropping how to solve this help me?

Can't mass-assign protected attributes: crop_x, crop_y, crop_w, crop_h

When you add resize_to_limit(600, 600) to the crop method to solve the problem that the x,y,width,height are relative to the :large image, it seems like you potentially lose some resolution.

It certainly makes sense to scale the image down to something reasonable before displaying it in the cropping UI, but if you're using this to generate a new image that's bigger than a thumbnail, it would be really nice to be cropping from the big image, not the 600x600 one. Seems like it would be better to scale the x, y, width and height values to work with the original image rather than scale the image.

What would be the most efficient way to get the dimensions of the original image in the crop method so that one could scale the values instead of scaling the image?

Anyone have the problem of it occasionally not cropping the image after the upload?

Occasionally one slips by.

All the necessary scripts (jquery, jcrop, avatar.js) are loaded but I'm getting a:
Uncaught TypeError: Object [object Object] has no method 'Jcrop'

I also have bootstrap.js loaded. I cannot figure out what's going on. Does anyone have any idea? Posted my question here, too:
http://stackoverflow.com/questions/14132170/uncaught-typeerror-object-object-object-has-no-method-jcrop

thanks!

Has anyone got jCrop working with ActiveAdmin? If so, how would you pass the instance variable to the render template?

It looks like CarrierWave isn't passing the correct instance to the uploader in recreate_versions. I have opened a ticket here:

https://github.com/jnicklas/carrierwave/issues/1015

Until this is fixed, this method Ryan uses here is currently broken.

I couldn't get cropping to work with mini magick, but after trying some different things I still managed. Seems like someone has switched around on (X, Y) and (W, H).

This should work:

def crop
  manipulate! do |img|
    img.crop "#{model.width}x#{model.height}+#{model.x}+#{model.y}"
    img
  end
end