Machine-readable optical label including spectrally encoded data storage patterns

Methods, systems, and computer program products for storing data in, and reading data from, machine-readable optical labels are disclosed. A machine-readable optical label includes a data storage layer and a substrate having a reflective surface. The data storage layer defines a plurality of data storage patterns in each of a corresponding number of absorption bands. Each of the data storage patterns encodes a portion of the data stored in the label as a reflectivity of the label in the absorption band of the data storage pattern. The label is read by capturing images of the label in each of a plurality of color channels, with each color channel including one absorption band and excluding the other absorption bands. The data stored by each data storage pattern is then decoded from the image in the corresponding color channel.