RubyでWeb画面キャプチャして切り取る

環境

# cat /etc/redhat-release
CentOS Linux release 7.2.1511 (Core)

セットアップ

install

package

# yum -y install firefox
# yum -y install xorg-x11-server-Xvfb
# yum -y install ImageMagick.x86_64 ImageMagick-devel.x86_64
# yum -y groupinstall "Japanese Support"
# yum -y install ipa-pgothic-fonts.noarch

gem

# gem install selenium-webdriver
# gem install rmagick

設定

# vi ~/.vi ~/.bash_profile
export DISPLAY=:1

起動

# Xvfb :1 -screen 0 1024x768x24 &
# firefox &

コード

#! /usr/bin/env ruby

require "selenium-webdriver"
require 'rmagick'

driver = Selenium::WebDriver.for :firefox
driver.get("http://counting.hatelabo.jp/count/hei5ifub5x")
driver.save_screenshot("hatena_counting.png")
driver.quit

image = Magick::ImageList.new("hatena_counting.png").crop(0, 68, 502, 250)
image.write("hatena_counting500x250.png")