I represent the table of values used to decode Huffman entropy-encoded bitstreams. From the JFIF file header entropy values, I build a derived table of codes and values for faster decoding.

	computation
	makeDerivedTables valueForCode:length:

	initialization
	initialize

	accessing	top
	bits:
	lookaheadBits
	lookaheadSymbol
	maxcode
	values:

	computation	top
	makeDerivedTables
	valueForCode:length:

	constants	top
	lookahead

	initialization	top
	initialize Object initialize