lib/image_voodoo.rb in image_voodoo-0.2 vs lib/image_voodoo.rb in image_voodoo-0.3
- old
+ new
@@ -1,18 +1,31 @@
-# ImageVoodoo is an ImageScience-API-compatible image manipulation library for JRuby.
#
-# Example of usage:
+# = ImageVoodoo
+# == Description
#
+# ImageVoodoo is an ImageScience-API-compatible image manipulation library for
+# JRuby.
+#
+# == Examples
+#
+# === Simple block-based examples
+#
# ImageVoodoo.with_image(ARGV[0]) do |img|
# img.cropped_thumbnail(100) { |img2| img2.save "CTH.jpg" }
# img.with_crop(100, 200, 400, 600) { |img2| img2.save "CR.jpg" }
# img.thumbnail(50) { |img2| img2.save "TH.jpg" }
# img.resize(100, 150) do |img2|
# img2.save "HEH.jpg"
# img2.save "HEH.png"
# end
# end
+#
+# === Non-block return (not image_science compatible)
+#
+# img = ImageVoodoo.with_image(ARGV[0])
+# negative_img = img.negative
+#
class ImageVoodoo
include Java
import java.awt.RenderingHints
import java.awt.color.ColorSpace
@@ -21,45 +34,92 @@
import java.awt.image.ColorConvertOp
import java.awt.image.LookupOp
import java.awt.image.RescaleOp
import java.awt.image.BufferedImage
JFile = java.io.File
- BAIS = java.io.ByteArrayInputStream
- BAOS = java.io.ByteArrayOutputStream
+ import java.io.ByteArrayInputStream
+ import java.io.ByteArrayOutputStream
import javax.imageio.ImageIO
import javax.swing.JFrame
NEGATIVE_OP = LookupOp.new(ByteLookupTable.new(0, (0...254).to_a.reverse.to_java(:byte)), nil)
GREY_OP = ColorConvertOp.new(ColorSpace.getInstance(ColorSpace::CS_GRAY), nil)
- class JImagePanel < javax.swing.JPanel
- def initialize(image, x=0, y=0)
- super()
- @image, @x, @y = image, x, y
- end
- def image=(image)
- @image = image
- invalidate
- end
- def getPreferredSize
- java.awt.Dimension.new(@image.width, @image.height)
- end
- def paintComponent(graphics)
- graphics.drawImage(@image.to_java, @x, @y, nil)
- end
- end
-
def initialize(src)
@src = src
end
- # Foreach pixel new_pixel = pixel * scale + offset
+ #
+ # Add a border to the image and yield/return a new image. The following
+ # options are supported:
+ # - width: How thick is the border (default: 3)
+ # - color: Which color is the border (in rrggbb hex value)
+ # - style: etched, raised, plain (default: plain)
+ #
+ def add_border(options = {})
+ border_width = options[:width].to_i || 2
+ color = hex_to_color(options[:color]) || hex_to_color("000000")
+ style = options[:style]
+ style = nil if style.to_sym == :plain
+ new_width, new_height = width + 2*border_width, height + 2*border_width
+ target = BufferedImage.new(new_width, new_height, color_type)
+ graphics = target.graphics
+ graphics.color = color
+ if style
+ raised = style.to_sym == :raised ? true : false
+ graphics.fill3DRect(0, 0, new_width, new_height, raised)
+ else
+ graphics.fill_rect(0, 0, new_width, new_height)
+ end
+ graphics.draw_image(@src, nil, border_width, border_width)
+ graphics.dispose
+ target = ImageVoodoo.new target
+ block_given? ? yield(target) : target
+ end
+
+ #
+ # Adjusts the brightness of each pixel in image by the following formula:
+ # new_pixel = pixel * scale + offset
+ #
def adjust_brightness(scale, offset)
image = ImageVoodoo.new internal_transform(RescaleOp.new(scale, offset, nil))
block_given? ? yield(image) : image
end
+ #
+ # Converts rgb hex color value to an alpha value an yields/returns the new
+ # image.
+ #
+ def alpha(rgb)
+ color = hex_to_color(rgb)
+ target = BufferedImage.new(width, height, BufferedImage::TYPE_INT_ARGB)
+ graphics = target.graphics
+ graphics.set_composite(java.awt.AlphaComposite::Src)
+ graphics.draw_image(@src, nil, 0, 0)
+ graphics.dispose
+ 0.upto(height-1) do |i|
+ 0.upto(width-1) do |j|
+ target.setRGB(j, i, 0x8F1C1C) if target.getRGB(j, i) == color.getRGB
+ end
+ end
+ target = ImageVoodoo.new target
+ block_given? ? yield(target) : target
+ end
+
+ #
+ # Write current image out as a stream of bytes using provided format.
+ #
+ def bytes(format)
+ out = ByteArrayOutputStream.new
+ ImageIO.write(@src, format, out)
+ String.from_java_bytes(out.to_byte_array)
+ end
+
+ #
+ # Creates a square thumbnail of the image cropping the longest edge to
+ # match the shortest edge, resizes to size, and yields/returns the new image.
+ #
def cropped_thumbnail(size)
l, t, r, b, half = 0, 0, width, height, (width - height).abs / 2
l, r = half, half + height if width > height
t, b = half, half + width if height > width
@@ -69,27 +129,55 @@
block_given? ? yield(target) : target
end
end
end
- def height
- @src.height
+ #
+ # Flips the image horizontally and yields/returns the new image.
+ #
+ def flip_horizontally
+ target = BufferedImage.new(width, height, color_type)
+ graphics = target.graphics
+ graphics.draw_image(@src, 0, 0, width, height, width, 0, 0, height, nil)
+ graphics.dispose
+ target = ImageVoodoo.new target
+ block_given? ? yield(target) : target
end
- def width
- @src.width
+ #
+ # Flips the image vertically and yields/returns the new image.
+ #
+ def flip_vertically
+ target = BufferedImage.new(width, height, color_type)
+ graphics = target.graphics
+ graphics.draw_image(@src, 0, 0, width, height, 0, height, width, 0, nil)
+ graphics.dispose
+ target = ImageVoodoo.new target
+ block_given? ? yield(target) : target
end
- def to_java
- @src
+ #
+ # Creates a grayscale version of image and yields/returns the new image.
+ #
+ def greyscale
+ image = ImageVoodoo.new internal_transform(GREY_OP)
+ block_given? ? yield(image) : image
end
+ alias_method :grayscale, :greyscale
+ #
+ # Creates a negative and yields/returns the new image.
+ #
def negative
image = ImageVoodoo.new internal_transform(NEGATIVE_OP)
block_given? ? yield(image) : image
end
+ #
+ # Resizes the image to width and height using bicubic interpolation and
+ # yields/returns the new image.
+ #
def resize(width, height)
target = BufferedImage.new(width, height, color_type)
graphics = target.graphics
graphics.set_rendering_hint(RenderingHints::KEY_INTERPOLATION,
RenderingHints::VALUE_INTERPOLATION_BICUBIC)
@@ -103,64 +191,100 @@
block_given? ? yield(target) : target
rescue NativeException => ne
raise ArgumentError, ne.message
end
- def greyscale
- image = ImageVoodoo.new internal_transform(GREY_OP)
- block_given? ? yield(image) : image
- end
-
+ #
+ # Saves the image out to path. Changing the file extension will convert
+ # the file type to the appropriate format.
+ #
def save(file)
format = File.extname(file)
return false if format == ""
format = format[1..-1].downcase
ImageIO.write(@src, format, JFile.new(file))
true
end
+ #
+ # Resize (scale) the current image by the provided ratio and yield/return
+ # the new image.
+ #
+ def scale(ratio)
+ new_width, new_height = (width * ratio).to_i, (height * ratio).to_i
+
+ resize(new_width, new_height) do |image|
+ target = ImageVoodoo.new image
+ block_given? ? yield(target) : target
+ end
+ end
+
+ #
+ # Creates a proportional thumbnail of the image scaled so its longest
+ # edge is resized to size and yields/returns the new image.
+ #
+ def thumbnail(size)
+ scale(size.to_f / (width > height ? width : height))
+ end
+
+ #
+ # Crops an image to left, top, right, and bottom and then yields/returns the
+ # new image.
+ #
+ def with_crop(left, top, right, bottom)
+ image = ImageVoodoo.new @src.get_subimage(left, top, right-left, bottom-top)
+ block_given? ? yield(image) : image
+ end
+
+ #
+ # A simple swing wrapper around an image voodoo object.
+ #
+ class JImagePanel < javax.swing.JPanel
+ def initialize(image, x=0, y=0)
+ super()
+ @image, @x, @y = image, x, y
+ end
+
+ def image=(image)
+ @image = image
+ invalidate
+ end
+
+ def getPreferredSize
+ java.awt.Dimension.new(@image.width, @image.height)
+ end
+
+ def paintComponent(graphics)
+ graphics.drawImage(@image.to_java, @x, @y, nil)
+ end
+ end
+
+ # Internal class for closing preview window
class WindowClosed
def initialize(block = nil)
@block = block || proc { java.lang.System.exit(0) }
end
def method_missing(meth,*args); end
def windowClosing(event); @block.call; end
end
+ #
+ # Creates a viewable frame displaying current image within it.
+ #
def preview(&block)
frame = JFrame.new("Preview")
frame.add_window_listener WindowClosed.new(block)
frame.set_bounds 0, 0, width + 20, height + 40
frame.add JImagePanel.new(self, 10, 10)
frame.visible = true
end
- def bytes(format)
- out = BAOS.new
- ImageIO.write(@src, format, out)
- String.from_java_bytes(out.to_byte_array)
- end
-
- def scale(ratio)
- new_width = (width * ratio).to_i
- new_height = (height * ratio).to_i
- resize(new_width, new_height) do |image|
- target = ImageVoodoo.new image
- block_given? ? yield(target) : target
- end
- end
-
- def thumbnail(size)
- scale(size.to_f / (width > height ? width : height))
- end
-
- def with_crop(left, top, right, bottom)
- image = ImageVoodoo.new(@src.get_subimage(left, top, right-left, bottom-top))
- block_given? ? yield(image) : image
- end
-
+ #
# TODO: Figure out how to determine whether source has alpha or not
+ # Experimental: Read an image from the url source and yield/return that
+ # image.
+ #
def self.from_url(source)
url = java.net.URL.new(source)
image = java.awt.Toolkit.default_toolkit.create_image(url)
tracker = java.awt.MediaTracker.new(java.awt.Label.new(""))
tracker.addImage(image, 0);
@@ -173,30 +297,75 @@
block_given? ? yield(target) : target
rescue java.io.IOException, java.net.MalformedURLException
raise ArgumentError.new "Trouble retrieving image: #{$!.message}"
end
+ #
+ # A top-level image loader opens path and then yields/returns the image.
+ #
def self.with_image(file)
readers = ImageIO.getImageReadersBySuffix(File.extname(file)[1..-1])
raise TypeError, "unrecognized format for #{file}" unless readers.hasNext
image = ImageVoodoo.new ImageIO.read(JFile.new(file))
block_given? ? yield(image) : image
rescue NativeException => ne
nil
end
+ #
+ # A top-level image loader reads bytes and then yields/returns the image.
+ #
def self.with_bytes(bytes)
bytes = bytes.to_java_bytes if String === bytes
- image = ImageVoodoo.new ImageIO.read(BAIS.new(bytes))
+ image = ImageVoodoo.new ImageIO.read(ByteArrayInputStream.new(bytes))
block_given? ? yield(image) : image
end
+ #
+ # Returns the height of the image, in pixels.
+ #
+ def height
+ @src.height
+ end
+
+ #
+ # Returns the width of the image, in pixels.
+ #
+ def width
+ @src.width
+ end
+
+ #
+ # Returns the underlying Java BufferedImage associated with this object.
+ #
+ def to_java
+ @src
+ end
+
private
+
+ #
+ # Converts a RGB hex value into a java.awt.Color object or dies trying
+ # with an ArgumentError.
+ #
+ def hex_to_color(rgb)
+ raise ArgumentError.new "hex rrggbb needed" if rgb !~ /[[:xdigit:]]{6,6}/
+
+ java.awt.Color.new(rgb[0,2].to_i(16), rgb[2,2].to_i(16), rgb[4,2].to_i(16))
+ end
+
+ #
+ # Determines the best colorspace for a new image based on whether the
+ # existing image contains an alpha channel or not.
+ #
def color_type
return BufferedImage::TYPE_INT_ARGB if @src.color_model.has_alpha
BufferedImage::TYPE_INT_RGB
end
+ #
+ # Do simple AWT operation transformation to target.
+ #
def internal_transform(operation, target=BufferedImage.new(width, height, color_type))
graphics = target.graphics
graphics.drawImage(@src, 0, 0, nil)
graphics.drawImage(operation.filter(target, nil), 0, 0, nil)
graphics.dispose