### Home Classes Methods

### In Files

- lib/prawn/images.rb
- lib/prawn/images/image.rb
- lib/prawn/images/png.rb
- lib/prawn/images/jpg.rb

### Namespace

- CLASS Prawn::Images::Image
- CLASS Prawn::Images::JPG
- CLASS Prawn::Images::PNG

### Methods

- #build_image_object
- #embed_image
- #image

### Class/Module Index

Quicksearch

- Prawn
- Prawn::Configurable
- Prawn::Document
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- Prawn::Document::ColumnBox
- Prawn::Document::GraphicsState
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- Prawn::Document::Internals
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- Prawn::Font::AFM
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- Prawn::Graphics
- Prawn::Graphics::CapStyle
- Prawn::Graphics::Color
- Prawn::Graphics::Dash
- Prawn::Graphics::JoinStyle
- Prawn::Graphics::Patterns
- Prawn::Graphics::Transformation
- Prawn::Graphics::Transparency
- Prawn::ImageHandler
- Prawn::Images
- Prawn::Images::Image
- Prawn::Images::JPG
- Prawn::Images::PNG
- Prawn::Measurements
- Prawn::SoftMask
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- Prawn::Table::Cell::Image
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- Prawn::Table::ColumnWidthCalculator
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- Prawn::Text::Formatted::Box
- Prawn::Text::Formatted::Fragment
- Prawn::Text::Formatted::Parser
- Prawn::ThreadLocalCache
- PDF
- PDF::Core
- PDF::Core::Reference
- PDF::Core::Stream
- Arcfour
- Numeric

No matching classes.

# Prawn::Images

### Public Instance Methods

build_image_object(file) click to toggle source

Builds an info object (Prawn::Images::*) and a PDF reference representing the given image. Return a pair: [pdf_obj, info].

@private

    # File lib/prawn/images.rb, line 77
    def build_image_object(file)
      io = verify_and_open_image(file)
      image_content = io.read
      image_sha1 = Digest::SHA1.hexdigest(image_content)

      # if this image has already been embedded, just reuse it
      if image_registry[image_sha1]
        info = image_registry[image_sha1][:info]
        image_obj = image_registry[image_sha1][:obj]
      else
        # Build the image object
        info = Prawn.image_handler.find(image_content).new(image_content)

        # Bump PDF version if the image requires it
        min_version(info.min_pdf_version) if info.respond_to?(:min_pdf_version)

        # Add the image to the PDF and register it in case we see it again.
        image_obj = info.build_pdf_object(self)
        image_registry[image_sha1] = {:obj => image_obj, :info => info}
      end

      [image_obj, info]
    end

embed_image(pdf_obj, info, options) click to toggle source

Given a PDF image resource `pdf_obj` that has been added to the page's resources and an `info` object (the pair returned from build_image_object), embed the image according to the `options` given.

@private

    # File lib/prawn/images.rb, line 107
    def embed_image(pdf_obj, info, options)
      # find where the image will be placed and how big it will be
      w,h = info.calc_image_dimensions(options)

      if options[:at]
        x,y = map_to_absolute(options[:at])
      else
        x,y = image_position(w,h,options)
        move_text_position h
      end

      # add a reference to the image object to the current page
      # resource list and give it a label
      label = "I#{next_image_id}"
      state.page.xobjects.merge!(label => pdf_obj)

      # add the image to the current page
      instruct = "\nq\n%.3f 0 0 %.3f %.3f %.3f cm\n/%s Do\nQ"
      add_content instruct % [ w, h, x, y - h, label ]
    end

image(file, options={}) click to toggle source

Add the image at filename to the current page. Currently only JPG and PNG files are supported. (Note that processing PNG images with alpha channels can be processor and memory intensive.)

Arguments:

`file` | path to file or an object that responds to read

Options:

`:at` | an array [x,y] with the location of the top left corner of the image.
`:position` | One of (:left, :center, :right) or an x-offset
`:vposition` | One of (:top, :center, :center) or an y-offset
`:height` | the height of the image [actual height of the image]
`:width` | the width of the image [actual width of the image]
`:scale` | scale the dimensions of the image proportionally
`:fit` | scale the dimensions of the image proportionally to fit inside [width,height]

    Prawn::Document.generate("image2.pdf", :page_layout => :landscape) do
      pigs = "#{Prawn::DATADIR}/images/pigs.jpg"
      image pigs, :at => [50,450], :width => 450

      dice = "#{Prawn::DATADIR}/images/dice.png"
      image dice, :at => [50, 450], :scale => 0.75
    end

If only one of :width / :height are provided, the image will be scaled proportionally. When both are provided, the image will be stretched to fit the dimensions without maintaining the aspect ratio.

If :at is provided, the image will be place in the current page but the text position will not be changed.

If instead of an explicit filename, an object with a read method is passed as `file`, you can embed images from IO objects and things that act like them (including Tempfiles and open-uri objects).

    require "open-uri"

    Prawn::Document.generate("remote_images.pdf") do
      image open("http://prawn.majesticseacreature.com/media/prawn_logo.png")
    end

This method returns an image info object which can be used to check the dimensions of an image object if needed. (See also: Prawn::Images::PNG , Prawn::Images::JPG)

    # File lib/prawn/images.rb, line 62
    def image(file, options={})
      Prawn.verify_options [:at, :position, :vposition, :height,
                            :width, :scale, :fit], options

      pdf_obj, info = build_image_object(file)
      embed_image(pdf_obj, info, options)

      info
    end

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