Pulse Width Modulation is one of the original techniques for encoding and decoding barcode symbols and is still in use today. Initially developed for use within libraries, PWM barcodes such as Plessey Code and MSI are still being used in a wide variety of industries and applications.
MSI / Modified Plessey Code
MSI is a variation of the Plessey Code symbol which can encode the numbers 0-9 and is used to identify shelving locations in retail stores. MSI symbols can be any length and contain one or two check digits.
LEADTOOLS symbology identifier
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