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ruby-on-railsherokuimagemagickrmagick

How to manipulate PNG images using ImageMagick on Heroku

I'm using rmagick gem, and I had to install the PNG library from here locally. 

$ convert --version
Version: ImageMagick 6.8.9-1 Q16 x86_64 2014-05-12 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2014 ImageMagick Studio LLC
Features: DPC Modules
Delegates: bzlib freetype jng jpeg ltdl lzma png xml zlib

But on Heroku, I don't have this delegate:

~ $ convert --version
Version: ImageMagick 6.7.7-10 2014-03-06 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC
Features: OpenMP

And it's impossible to install it, because Heroku don't let me use sudo.

Any ideas on how to solve this?

Update 17/11:

I already using the rmagick gem in my app. But, I have to manipulate PNG images and ImageMagick requires the png delegate to do this.

My problem isn't the gem. But the png delegate.

Solution

  • You can use a Heroku buildpack to install the dependencies.

    There's an ImageMagick buildpack available here. Just follow the instructions will do. Feel free to search "ImageMagick buildpack" on the web if you're not using Cedar14 stack.

    Update on Nov 17:

    Interesting, seems like Heroku already has ImageMagick installed(which explains why I don't have this problem when I use Paperclip gem) and it's pretty easy to require Rmagick class as show in this SO question. Explained in here too.

    gem "rmagick", :require => 'RMagick'