Gets the Decode array in effect: the dictionary's, else the default for the colour space and depth (Table 88). Two numbers per component; empty when the image cannot be decoded.
public IReadOnlyList<double> DecodeArray { get; }
ISO 32000-2 §8.9.5.2, Table 88. An Indexed image defaults to [0 2^n−1]; an image mask to [0 1]. An array too
short or not numeric is replaced by the default, one too long cut, both with a diagnostic. A JPEG 2000 image without a colour
space ignores the array (§7.4.9).