Small Aztec Code is a special space-saving version of Aztec Code for encoding shorter messages (up to 95 characters). Space is saved by removing one set of rings from the finder pattern, eliminating the reference grid, and using a shorter mode message which limits the symbols to four data layers; otherwise, the encoding rules are generally the same as for standard Aztec Code. Small Aztec symbols are completely decoder compatible with standard Aztec symbols so the two types can be intermixed in applications.

There are four possible sizes of Small Aztec symbol. As with standard Aztec Code, the one and two layer symbols employ 6-bit codewords for error correction while the three and four layer symbols employ 8-bit codewords. Although the 4-layer symbol holds 76 codewords, at most 64 of those can be data words, thus Small Aztec symbols are limited to encoding 512 bits of data (typically about 95 characters or 120 digits).

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