utzel-butzel/bmp-reader

This JavaScript package decodes the payload from German Bundeseinheitlicher Medikationsplan, or BMP, barcodes. BMP is a standardized medication plan format used in German healthcare. Pharmacies and doctors print patient medication plans as sheets containing a DataMatrix 2D barcode. When a scanner reads that barcode, it returns a compact XML string encoded in ISO-8859-1. This library takes that scanner output and converts it into a structured JavaScript object with patient information, medication entries, and any warnings from the data. The library does not do camera scanning or image processing. It starts after a barcode scanner or image library has already read the DataMatrix code and returned the raw text or bytes. Passing the scanner output to the decodeBmp function returns a plan object with fields for the patient's name, medications, and other sections from the BMP data. Multi-page BMP printouts are supported. Some medication plans span more than one page, each printed with its own DataMatrix code. The decodeBmpPages function accepts an array of scanned page payloads, validates that they belong to the same instance, sorts them, and merges the sections into one assembled plan. The package supports BMP versions 2.7 and 2.8 by default, which are the currently active versions. Older versions 2.6 and 2.3 can be parsed with an option flag but are not officially claimed as fully supported. The library throws an error with a stable error code when it encounters an unsupported version or malformed input, so integrators can catch and handle specific failure cases. A note on encoding: BMP payloads use ISO-8859-1, not UTF-8. If your scanner returns a text string, each byte must map directly to its character code or German characters such as umlauts will be corrupted. The library accepts raw bytes as Uint8Array or ArrayBuffer to avoid this problem, and the README recommends passing bytes directly where possible.