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Questions tagged [rmagick]

RMagick is an interface between the Ruby programming language and the ImageMagick® and GraphicsMagick image processing libraries.

RMagick is an interface between the Ruby programming language and the ImageMagick® and GraphicsMagick image processing libraries.

Questions concerning using ImageMagick® and GraphicsMagick image editing libraries with Ruby should be tagged with rmagick.

853 questions
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Rmagick unable to read font

I have a piece of code that draws text on top of an image in my Rails app and since short while ago, probably having to to with upgrading to OS X Yosemite, it's having an issue with reading fonts on my local machine (production server is working…
Cristian
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checking for ImageMagick version >= 6.4.9... no Can't install RMagick 2.13.4. You must have ImageMagick 6.4.9 or later

I have trouble installing rmagick. I am developing my project using ruby on rails framework. I included rmagick gem in my gemfile. I am getting the following error message: checking for ImageMagick version >= 6.4.9... no Can't install RMagick…
MBJH
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10 answers

Ruby gem rmagick won't install on Mac OS X

I understand that this question has been asked a lot earlier, but none of the solutions worked for me and I'm really desperate right now. I'm trying to get rMagick to install using gem for an installation of diaspora. I already installed imagick via…
knurb
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3 answers

Installing rmagick 2.13.1 with graphicsmagick on Ubuntu 10.04

I previously had an rmagick gem installation that works with ImageMagick. ImageMagick was installed from source with OpenMP disabled. This installation works without a hitch. However I attempted to uninstall rmagick and ImageMagick so that I could…
Lester Celestial
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13
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3 answers

RMagick remove white background from image and make it transparent

I need to remove the white background from this image and make the background transparent. So it's just a black tick on the transparent background exported as a png. e.g. Turn Into Any ideas?
Tom
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13
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5 answers

RMagick can not read remote image

My env is Linux centos, and use ruby 1.8.7, and the code is here below: require 'rubygems' require 'RMagick' Magick::Image.read("http://image.domain.com/image.darenhui.com/images/random_bg/01.jpg")[0] it throws error like below: in `read': no…
ywenbo
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Is it possible to get the average image color with RMagick?

I need to know the average color from an image when I upload it to my Ruby on Rails application. Is it possible to get the average color value in HEX or in RGB to use this color later in the view that's going to display this image? Something…
Mr_Nizzle
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6 answers

MiniMagick - cannot load such file

I'm trying to use MiniMagick to resize images and I did the following in my controller file: require 'rubygems' require 'mini_magick' and img = MiniMagick::Image.open(file) But when I invoke the controller the following LoadError (cannot load…
Guanlun
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5 answers

How to detect if two images are the same with different cropping ratios?

I have two different images with different dimensions: 100px and 400px As you can see the two are clearly the "same" from a human point of view. Now I wanna detect if they are the same. I have been using image magic via the ruby gem called…
Niels Kristian
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4 answers

Can't find wand/MagickWand.h

I have update my system to Ubuntu 15.04 and now Rmagick can't be installed... It gives me the following error: $ gem install rmagick -v '2.13.2' Building native extensions. This could take a while... ERROR: Error installing rmagick: ERROR:…
Maria-Christina Rus
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9 answers

Installing RMagick gem -- Can't find MagickWand.h

I am installing the rmagick gem on OSX 10.6.8, using gem install rmagick, and I am getting the following error Can't install RMagick 2.13.1. Can't find MagickWand.h. *** extconf.rb failed *** Could not create Makefile due to some reason,…
Dave Isaacs
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ImageMagickError unable to read font `(null)': `(null)'

I've been getting this error for a while on my production server (Ubuntu running ImageMagick, Rmagick, etc). From Googling around it seems to be not finding the right fonts to use, and this needs to be set correctly in sudo nano…
Brian Armstrong
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4 answers

ImageMagick - "CORE_RL_magick_.dll not found" or how to install RMagick on windows with ruby 1.9.2

I'm working on a Rail3 app. After struggling for several hours and finally installing the rmagick 2.13.1 gem without errors on win7x64 / ruby 1.9.2, I've run into another error. Yeah, I've heard that rails experience in windows could be…
bassneck
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2 answers

Installing RMagick Gem

I just wanted to gem install rmagick and got this: Building native extensions. This could take a while... ERROR: Error installing rmagick: ERROR: Failed to build gem native extension. /usr/bin/ruby1.8 extconf.rb extconf.rb:1:in `require': no…
Joern Akkermann
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Loss of PNG image quality following CarrierWave::RMagick resize_to_fit

I'm using CarrierWave::RMagick to create thumbnail versions of images for a Rails app, and I've noticed loss of quality when the images are downsized. This is understandable to a certain extent, as we have less pixels in a downsized image and…
Merott
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