Storing barcodes as ASCII

Question

I am currently looking at a TIFF file generated by a microscope vendor. They store an XML within the TIFF (ImageDescription tag). Within this XML I can find a <barcode> element. But instead of storing the actual barcode (PDF417, DataMatrix) value, they store something else.

I have three samples, first one is a PDF417, the last two are DataMatrix. Decoding the values leads to:

1. 04050629C
2. H13150154711A11
3. H13150154512A02

while the XML element <barcode> contains (in that order):

1. MDQwNTA2MjlD
2. SDEzMTUwMTU0NzExQTEx
3. SDEzMTUwMTU0NTEyQTAy

What type of encoding is this ?

Answer 1

The type of encoding is Base64 encoding.

$ echo MDQwNTA2MjlD | base64 -d
04050629C

$ echo SDEzMTUwMTU0NzExQTEx | base64 -d
H13150154711A11