Howto resize multiple pictures, graphics, images
for k in $(ls *.jpg); do convert -resize 800 -quality 80 $k r800-$k; done
Never been to DZone Snippets before?
Snippets is a public source code repository. Easily build up your personal collection of code snippets, categorize them with tags / keywords, and share them with the world
Batch re-size a collection of images from the command line
for img in $(ls *.png); do convert $img -resize 75% smaller-$img; done;
Generate a graph using Gruff
This Ruby code produced a graph using gruff. The output shows a line graph [twitxr.com] for the different fruits. Source code origin: Gruff Update With Bar Graphs | Ruby on Rails for Newbies [rubyonrails.com]
Note: I executed the code within an irb session on my Gentoo box. With Gentoo, Gruff was installed [gentoo-portage.com] using the command emerge -va gruff. I tried installing it on Ubuntu but ran into some difficulty, even with help from the article install rmagick ubuntu [dzone.com].
*udpate 21:48 24-Feb*
The following code does exactly as the same code above, however it uses XML to separate the data from the process, making it easier and more efficient to build graphs.
file: my_fruit.xml
Reference: gruff's gruff-0.2.9 Documentation [rubyforge.org]
to ruby rmagick image ubuntu gentoo magick graph chart gruff by jrobertson on Feb 24, 2008
require 'gruff' g = Gruff::Line.new g.title = "My Graph" g.data("Apples", [1, 2, 3, 4, 4, 3]) g.data("Oranges", [4, 8, 7, 9, 8, 9]) g.data("Watermelon", [2, 3, 1, 5, 6, 8]) g.data("Peaches", [9, 9, 10, 8, 7, 9]) g.labels = {0 => '2003', 2 => '2004', 4 => '2005'} g.write('my_fruity_graph.png')
Note: I executed the code within an irb session on my Gentoo box. With Gentoo, Gruff was installed [gentoo-portage.com] using the command emerge -va gruff. I tried installing it on Ubuntu but ran into some difficulty, even with help from the article install rmagick ubuntu [dzone.com].
*udpate 21:48 24-Feb*
The following code does exactly as the same code above, however it uses XML to separate the data from the process, making it easier and more efficient to build graphs.
#!/usr/bin/ruby # file: xml2gruff.rb require 'rexml/document' require 'gruff' include REXML class Xml2Gruff def initialize(filename) file = File.new(filename, 'r') doc = Document.new(file) # get the title @title = doc.root.elements['summary/title'].text @record = Hash.new # get each record doc.root.elements.each('records/item') {|item| avalues = Array.new item.elements.each('values/value') { |value| avalues << value.text.to_i } @record[item.elements['label'].text] = avalues } # get the summary labels @labels = Hash.new doc.root.elements.each('summary/scale/label') {|l| @labels[l.elements['value'].text.to_i] = l.elements['title'].text} end def save_line_graph(filename) g = Gruff::Line.new g.title = @title @record.each {|label, data| g.data(label, data) } g.labels = @labels g.write(filename) end end if __FILE__ == $0 x2g = Xml2Gruff.new('my_fruit.xml') x2g.save_line_graph('my_fruit2.png') end
file: my_fruit.xml
<graph> <summary> <title>My Graph</title> <scale> <label><title>2003</title><value>0</value></label> <label><title>2004</title><value>2</value></label> <label><title>2005</title><value>4</value></label> </scale> </summary> <records> <item> <label>Apples</label> <values><value>1</value><value>2</value><value>3</value><value>4</value><value>4</value><value>3</value></values> </item> <item> <label>Oranges</label> <values><value>4</value><value>8</value><value>7</value><value>9</value><value>8</value><value>9</value></values> </item> <item> <label>Watermelon</label> <values><value>2</value><value>3</value><value>1</value><value>5</value><value>6</value><value>8</value></values> </item> <item> <label>Peaches</label> <values><value>9</value><value>9</value><value>10</value><value>8</value><value>7</value><value>9</value></values> </item> </records> </graph>
Reference: gruff's gruff-0.2.9 Documentation [rubyforge.org]
to ruby rmagick image ubuntu gentoo magick graph chart gruff by jrobertson on Feb 24, 2008
Avatar Resizer
I go on a lot of Bulletin Board, every has its own limits of size for the avatars, instead of the resize manually I created a script which does it for me with RMagick
#!/usr/bin/ruby require "RMagick" $SIZES = [80 , 100 , 110 , 128] if !ARGV[0] puts "Usage: mk_avatars.rb SourceAvatarPath" exit end image = Magick::Image.read(ARGV[0]).first $SIZES.each do |sz| puts "Generating Avatar : #{sz}" out = image.thumbnail(sz,sz) file = "out_#{sz}.#{image.format}" out.write(file) end
Resizing images using RMagick
require 'rubygems' require 'RMagick' include Magick def append_filename(filename, suffix) extrac = filename.split('.') extrac[-2] += suffix extrac.join('.') end ARGV.each do |f| ImageList.new(f).resize(800, 600).write(append_filename(f, '_l')) ImageList.new(f).resize(400, 300).write(append_filename(f, '_m')) ImageList.new(f).resize(40, 30).write(append_filename(f, '_s')) end
