An exceptionally dense information encoding system, with 4-10 times the density of CD ROM diskettes, employs colored areas in the form of bars or checkerboard matrices of colored dot regions to encode information including alphanumerics, with each colored region being variable as to both color and intensity. In one embodiment, so-called super pixel dots have differently colored sub-regions within them, arranged with side-by-side colors or with colored regions stacked one on top of the other, such that information from one dot has as many color variables as there are stacked layers or mixed colors. In one embodiment the super pixel dot is 5 microns in diameter with 2 micron spacing between adjacent dots. For each color in one embodiment there are as many as 64 intensities yielding a coding system of high information density. The various colors are read out at one super pixel dot position by dividing out reflected or transmitted energy from a dot by color filtering such that a color and intensity can be detected for each color intensity within the super pixel dot. The code provided by the subject system is substantially invisible to the naked eye, with machine vision and computer analysis of the information being required to effectively decode differences of intensity. Additionally, encrypting can be performed on the digitally encoded information to further hide the information carried by the colored dot matrix. Moreover, standardized intensities are established by one or more of the coded regions to assist in machine decoding, and correction techniques are applied for variations in detected color and intensity.