The data codewords follow starting with the most significant encodable character. Function codewords may be inserted to achieve data compaction. Pad codewords are subsequently added to enable the codeword sequence to be represented in a rectangular matrix. Pad codewords may also be used to fill additional complete rows to achieve the desired aspect ratio or as specified by an application. An optional Macro PDF417 Control Block.
Error correction codewords for error detection and correction.
The codewords are arranged with the most significant codeword adjacent to the symbol length descriptor, and are encoded from left to right top row to bottom. Figure 2 illustrates in layout format the sequence for the symbol like that shown in Figure 1. In Figure 2 an error correction level of 1 has been used and one pad character was needed to completely fill the symbol matrix. The rules and advice for structuring the matrix are included in the table below. All Rights Reserved.