Method: NuWav::WaveFile#parse

Defined in:
lib/nu_wav/wave_file.rb

#parse(wave_file) ⇒ Object 



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# File 'lib/nu_wav/wave_file.rb', line 15

def parse(wave_file)
  NuWav::WaveFile.log "Processing wave file #{wave_file.inspect}...."
  wave_file_size = File.size(wave_file)

  File.open(wave_file, 'r') do |f|

    #only for windows, make sure we are operating in binary mode 
    f.binmode
    #start at the very beginning, a very good place to start
    f.seek(0)

    riff, riff_length = read_chunk_header(f)
    NuWav::WaveFile.log "riff: #{riff}"
    NuWav::WaveFile.log "riff_length: #{riff_length}"
    NuWav::WaveFile.log "wave_file_size: #{wave_file_size}"

    raise NotRIFFFormat unless riff == 'RIFF' || riff == 'RF64'
    riff_end = [f.tell + riff_length, wave_file_size].min

    riff_type = f.read(4)
    raise NotWAVEFormat unless riff_type == 'WAVE'

    @header = RiffChunk.new(riff, riff_length, riff_type)

    while (f.tell + 8) <= riff_end
      NuWav::WaveFile.log "while #{f.tell} < #{riff_end}"
      chunk_name, chunk_length = read_chunk_header(f)
      fpos = f.tell

      NuWav::WaveFile.log "found chunk: '#{chunk_name}', size #{chunk_length}"
      
      if chunk_name && chunk_length

        self.chunks[chunk_name.to_sym] = chunk_class(chunk_name).parse(chunk_name, chunk_length, f)
        parsed_chunk_size = self.chunks[chunk_name.to_sym].size

        NuWav::WaveFile.log "about to do a seek..."
        NuWav::WaveFile.log "f.seek #{fpos} + #{parsed_chunk_size}"
        f.seek(fpos + parsed_chunk_size)
        NuWav::WaveFile.log "seek done"

        if parsed_chunk_size.odd?
          NuWav::WaveFile.log("parsed_chunk_size is ODD #{chunk_name}: #{parsed_chunk_size}")
          pad = f.read(1)
          if (pad.nil? || pad.ord != 0)
            NuWav::WaveFile.log("NOT PADDED")
            self.chunks[chunk_name.to_sym].pad_byte = false
            f.seek(fpos + parsed_chunk_size)
          else
            self.chunks[chunk_name.to_sym].pad_byte = true
          end
        end

      else
        NuWav::WaveFile.log "chunk or length was off - remainder of file does not parse properly: #{riff_end} - #{fpos} = #{riff_end - fpos}"
        f.seek(riff_end)
      end
    end
  end
  @chunks.each{|k,v| NuWav::WaveFile.log "#{k}: #{v}\n\n" unless k.to_s == 'data'}
  NuWav::WaveFile.log "parse done"
  self
end