Class: DynamicImage::Metadata

Inherits:
Object
  • Object
show all
Defined in:
lib/dynamic_image/metadata.rb

Overview

DynamicImage Metadata

Parses metadata from an image. Expects to receive image data as a binary string.

Instance Method Summary collapse

Constructor Details

#initialize(data) ⇒ Metadata

Returns a new instance of Metadata.



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# File 'lib/dynamic_image/metadata.rb', line 9

def initialize(data)
  @data = data
end

Instance Method Details

#colorspace ⇒ Object

Returns the color space of the image as a string. The result will be one of the following: “rgb”, “cmyk”, “gray”.



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# File 'lib/dynamic_image/metadata.rb', line 15

def colorspace
  return unless valid?

  case metadata[:colorspace]
  when /rgb/i
    "rgb"
  when /cmyk/i
    "cmyk"
  when /gray/i
    "gray"
  end
end

#content_type ⇒ Object

Returns the content type of the image.



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# File 'lib/dynamic_image/metadata.rb', line 29

def content_type
  "image/#{format.downcase}" if valid?
end

#dimensions ⇒ Object

Returns the dimensions of the image as a vector.



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# File 'lib/dynamic_image/metadata.rb', line 34

def dimensions
  Vector2d.new(*metadata[:dimensions]) if valid?
end

#format ⇒ Object

Returns the format of the image.



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# File 'lib/dynamic_image/metadata.rb', line 49

def format
  metadata[:format] if valid?
end

#height ⇒ Object

Returns the height of the image.



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# File 'lib/dynamic_image/metadata.rb', line 44

def height
  dimensions.try(:y)
end

#valid? ⇒ Boolean

Returns true if the image is valid.

Returns:

  • (Boolean) 


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# File 'lib/dynamic_image/metadata.rb', line 54

def valid?
  @data && reader.valid_header? && metadata != :invalid
end

#width ⇒ Object

Returns the width of the image.



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# File 'lib/dynamic_image/metadata.rb', line 39

def width
  dimensions.try(:x)
end