anchor: CompressedImageData:getWidth
  Gets the width of the CompressedImageData.
  width = CompressedImageData:getWidth()
  width number The width of the CompressedImageData.
  width = CompressedImageData:getWidth( level )
  level number A mipmap level. Must be in the range of CompressedImageData:getMipmapCount().
  width number The width of a specific mipmap level of the CompressedImageData.