Class: FastImage

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

Defined Under Namespace

Modules: StreamUtil Classes: CannotParseImage, Exif, FastImageException, FiberStream, Gif, IOStream, ImageFetchFailure, SizeNotFound, Svg, UnknownImageType

Constant Summary collapse

DefaultTimeout =
2
LocalFileChunkSize =
256

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(uri, options = {}) ⇒ FastImage

Returns a new instance of FastImage.


210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
# File 'lib/fastimage.rb', line 210

def initialize(uri, options={})
  @uri = uri
  @options = {
    :type_only        => false,
    :timeout          => DefaultTimeout,
    :raise_on_failure => false,
    :proxy            => nil,
    :http_header      => {}
  }.merge(options)

  @property = if @options[:animated_only]
    :animated
  elsif @options[:type_only]
    :type
  else
    :size
  end

  @type, @state = nil

  if uri.respond_to?(:read)
    fetch_using_read(uri)
  elsif uri.start_with?('data:')
    fetch_using_base64(uri)
  else
    begin
      @parsed_uri = URI.parse(uri)
    rescue URI::InvalidURIError
      fetch_using_file_open
    else
      if @parsed_uri.scheme == "http" || @parsed_uri.scheme == "https"
        fetch_using_http
      else
        fetch_using_file_open
      end
    end
  end

  raise SizeNotFound if @options[:raise_on_failure] && @property == :size && !@size

rescue Timeout::Error, SocketError, Errno::ECONNREFUSED, Errno::EHOSTUNREACH, Errno::ECONNRESET,
  Errno::ENETUNREACH, ImageFetchFailure, Net::HTTPBadResponse, EOFError, Errno::ENOENT,
  OpenSSL::SSL::SSLError
  raise ImageFetchFailure if @options[:raise_on_failure]
rescue NoMethodError  # 1.8.7p248 can raise this due to a net/http bug
  raise ImageFetchFailure if @options[:raise_on_failure]
rescue UnknownImageType
  raise UnknownImageType if @options[:raise_on_failure]
rescue CannotParseImage
  if @options[:raise_on_failure]
    if @property == :size
      raise SizeNotFound
    else
      raise ImageFetchFailure
    end
  end

ensure
  uri.rewind if uri.respond_to?(:rewind)

end

Instance Attribute Details

#animatedObject (readonly)

Returns the value of attribute animated


73
74
75
# File 'lib/fastimage.rb', line 73

def animated
  @animated
end

#bytes_readObject (readonly)

Returns the value of attribute bytes_read


75
76
77
# File 'lib/fastimage.rb', line 75

def bytes_read
  @bytes_read
end

#content_lengthObject (readonly)

Returns the value of attribute content_length


73
74
75
# File 'lib/fastimage.rb', line 73

def content_length
  @content_length
end

#orientationObject (readonly)

Returns the value of attribute orientation


73
74
75
# File 'lib/fastimage.rb', line 73

def orientation
  @orientation
end

#sizeObject (readonly)

Returns the value of attribute size


73
74
75
# File 'lib/fastimage.rb', line 73

def size
  @size
end

#typeObject (readonly)

Returns the value of attribute type


73
74
75
# File 'lib/fastimage.rb', line 73

def type
  @type
end

Class Method Details

.animated?(uri, options = {}) ⇒ Boolean

Returns a boolean value indicating the image is animated. It will return nil if the image could not be fetched, or if the image type was not recognised.

By default there is a timeout of 2 seconds for opening and reading from a remote server. This can be changed by passing a :timeout => number_of_seconds in the options.

If you wish FastImage to raise if it cannot find the type of the image for any reason, then pass :raise_on_failure => true in the options.

Example

require 'fastimage'

FastImage.animated?("test/fixtures/test.gif")
=> false
FastImage.animated?("test/fixtures/animated.gif")
=> true

Supported options

:timeout

Overrides the default timeout of 2 seconds. Applies both to reading from and opening the http connection.

:raise_on_failure

If set to true causes an exception to be raised if the image type cannot be found for any reason.

Returns:

  • (Boolean)

206
207
208
# File 'lib/fastimage.rb', line 206

def self.animated?(uri, options={})
  new(uri, options.merge(:animated_only=>true)).animated
end

.size(uri, options = {}) ⇒ Object

Returns an array containing the width and height of the image. It will return nil if the image could not be fetched, or if the image type was not recognised.

By default there is a timeout of 2 seconds for opening and reading from a remote server. This can be changed by passing a :timeout => number_of_seconds in the options.

If you wish FastImage to raise if it cannot size the image for any reason, then pass :raise_on_failure => true in the options.

FastImage knows about GIF, JPEG, BMP, TIFF, ICO, CUR, PNG, PSD, SVG and WEBP files.

Example

require 'fastimage'

FastImage.size("http://stephensykes.com/images/ss.com_x.gif")
=> [266, 56]
FastImage.size("http://stephensykes.com/images/pngimage")
=> [16, 16]
FastImage.size("http://farm4.static.flickr.com/3023/3047236863_9dce98b836.jpg")
=> [500, 375]
FastImage.size("http://www-ece.rice.edu/~wakin/images/lena512.bmp")
=> [512, 512]
FastImage.size("test/fixtures/test.jpg")
=> [882, 470]
FastImage.size("http://pennysmalls.com/does_not_exist")
=> nil
FastImage.size("http://pennysmalls.com/does_not_exist", :raise_on_failure=>true)
=> raises FastImage::ImageFetchFailure
FastImage.size("http://stephensykes.com/favicon.ico", :raise_on_failure=>true)
=> [16, 16]
FastImage.size("http://stephensykes.com/images/squareBlue.icns", :raise_on_failure=>true)
=> raises FastImage::UnknownImageType
FastImage.size("http://stephensykes.com/favicon.ico", :raise_on_failure=>true, :timeout=>0.01)
=> raises FastImage::ImageFetchFailure
FastImage.size("http://stephensykes.com/images/faulty.jpg", :raise_on_failure=>true)
=> raises FastImage::SizeNotFound

Supported options

:timeout

Overrides the default timeout of 2 seconds. Applies both to reading from and opening the http connection.

:raise_on_failure

If set to true causes an exception to be raised if the image size cannot be found for any reason.


136
137
138
# File 'lib/fastimage.rb', line 136

def self.size(uri, options={})
  new(uri, options).size
end

.type(uri, options = {}) ⇒ Object

Returns an symbol indicating the image type fetched from a uri. It will return nil if the image could not be fetched, or if the image type was not recognised.

By default there is a timeout of 2 seconds for opening and reading from a remote server. This can be changed by passing a :timeout => number_of_seconds in the options.

If you wish FastImage to raise if it cannot find the type of the image for any reason, then pass :raise_on_failure => true in the options.

Example

require 'fastimage'

FastImage.type("http://stephensykes.com/images/ss.com_x.gif")
=> :gif
FastImage.type("http://stephensykes.com/images/pngimage")
=> :png
FastImage.type("http://farm4.static.flickr.com/3023/3047236863_9dce98b836.jpg")
=> :jpeg
FastImage.type("http://www-ece.rice.edu/~wakin/images/lena512.bmp")
=> :bmp
FastImage.type("test/fixtures/test.jpg")
=> :jpeg
FastImage.type("http://stephensykes.com/does_not_exist")
=> nil
File.open("/some/local/file.gif", "r") {|io| FastImage.type(io)}
=> :gif
FastImage.type("test/fixtures/test.tiff")
=> :tiff
FastImage.type("test/fixtures/test.psd")
=> :psd

Supported options

:timeout

Overrides the default timeout of 2 seconds. Applies both to reading from and opening the http connection.

:raise_on_failure

If set to true causes an exception to be raised if the image type cannot be found for any reason.


178
179
180
# File 'lib/fastimage.rb', line 178

def self.type(uri, options={})
  new(uri, options.merge(:type_only=>true)).type
end