class ChunkyPNG::Datastream

def each_chunk
  yield(header_chunk)
  other_chunks.each { |chunk| yield(chunk) }
  yield(palette_chunk)      if palette_chunk
  yield(transparency_chunk) if transparency_chunk
  yield(physical_chunk)     if physical_chunk
  data_chunks.each { |chunk| yield(chunk) }
  yield(end_chunk)
end