Class: ID3Tag::AudioFile

Inherits:
Object
  • Object
show all
Defined in:
lib/id3tag/audio_file.rb

Constant Summary collapse

ID3V1_TAG_SIZE = 
128
ID3V2_TAG_HEADER_SIZE = 
10
IDV1_TAG_IDENTIFIER = 
"TAG"
IDV2_TAG_IDENTIFIER = 
"ID3"
BLANK_STRING = 
""

Instance Method Summary collapse

Constructor Details

#initialize(file) ⇒ AudioFile

Returns a new instance of AudioFile.



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# File 'lib/id3tag/audio_file.rb', line 9

def initialize(file)
  @file = file
end

Instance Method Details

#v1_tag_body ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 27

def v1_tag_body
  if v1_tag_present?
    @file.seek(-v1_tag_size, IO::SEEK_END)
    @file.read(v1_tag_size)
  else
    nil
  end
end

#v1_tag_present? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/id3tag/audio_file.rb', line 13

def v1_tag_present?
  if @file.size >= ID3V1_TAG_SIZE
    @file.seek(-ID3V1_TAG_SIZE, IO::SEEK_END)
    @file.read(3) == IDV1_TAG_IDENTIFIER
  else
    false
  end
end

#v1_tag_size ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 36

def v1_tag_size
  if v1_tag_present?
    ID3V1_TAG_SIZE - IDV1_TAG_IDENTIFIER.size
  else
    0
  end
end

#v2_tag_body ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 44

def v2_tag_body
  if v2_tag_size > 0
    @file.seek(v2_tag_frame_and_padding_position)
    bytes_to_read = v2_tag_frame_and_padding_size
    return BLANK_STRING if bytes_to_read < 0
    limit = ID3Tag.configuration.v2_tag_read_limit
    if (limit > 0) && (bytes_to_read > limit)
      bytes_to_read = limit
    end
    @file.read(bytes_to_read) || BLANK_STRING
  end
end

#v2_tag_major_version_number ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 69

def v2_tag_major_version_number
  v2_tag_header.major_version_number
end

#v2_tag_minor_version_number ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 73

def v2_tag_minor_version_number
  v2_tag_header.minor_version_number
end

#v2_tag_present? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/id3tag/audio_file.rb', line 22

def v2_tag_present?
  @file.seek(0)
  @file.read(3) == IDV2_TAG_IDENTIFIER
end

#v2_tag_size ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 57

def v2_tag_size
  if v2_tag_present?
    v2_tag_header.tag_size
  else
    0
  end
end

#v2_tag_version ⇒ Object 



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# File 'lib/id3tag/audio_file.rb', line 65

def v2_tag_version
  v2_tag_header.version_number
end