How to encode a GS1 using the DataMatrix format

[cah-brandon-trebbien]

What string should I pass to the datamatrix.py file so that I can have a GS1 encoded output with FNC1 characters and GS (group separators)?

i.e.
(01)00312345678901(21)040404(10)MYFAVLOT(17)201031

So that the appropriate function 1 characters are encoded into the barcode? Currently any attempt I have done (entering \x1d for example) has led to those characters actually being encoded straight into the text string itself.

i.e.
]d2(01)00312345678901(21)040404\x1d(10)MYFAVLOT\x1d(17)201031

My goal is to be able to scan this barcode and with the appropriate FNC1's or GS's inserted, the barcode can be parsed via standard GS1 logic.

This is an awesome project.. any help here would be greatly appreciated.

[emil-balashov]

@btrebbien I've used chr(231) as a group separator which I could find only by brute-force and comparing with the original barcode. According to the documentation it has to be 232 which is quite confusing. @mmulqueen would you mind to let me know if it's correct and update the documentation?

[Andreikaz]

@btrebbien I've used chr(231) as a group separator which I could find only by brute-force and comparing with the original barcode. According to the documentation it has to be 232 which is quite confusing. @mmulqueen would you mind to let me know if it's correct and update the documentation?

Emil, thank you so much! I've tried different libraries and didn't find right way to add FNC1 symbol. I tried chr(232) and \xe8, and only your solution gave me right result!

[klausmcm]

Any ideas on how this could be implemented in the algorithm so that a character like \xf1 can be passed into the encoder? When I include \xf1 in the string to be encoded, the generated barcode cannot be scanned.

[mmulqueen]

Sorry about the radio silence on this issue.

The reason that chr(231) works is because the encoding for ASCII characters is offset by 1.

e.g. ord("A") = 65, so the DataMatrix codeword for the letter A is 66.

The codeword for FNC1 is 232, so if pyStrich sees ç (\xe7 \u00e7), it translates that to the desired codeword.

This workaround relies on a bug, non-ASCII characters are improperly encoded by pyStrich - but you can assume this bug is now a feature!

def data_matrix_special_character(char):
    return chr(ord(char)-1)

FNC1 = data_matrix_special_character("\xf1")  # codeword 232
data = FNC1 + "019781910050262"

Disclaimer: I've not tested this thoroughly and we don't generate any GS1 barcodes ourselves - your mileage may vary!

[xjpf]

def data_matrix_special_character(char):
return chr(ord(char)-1)

FNC1 = data_matrix_special_character("\xf1") # codeword 232
data = FNC1 + "019781910050262"

this doesnt work.
You can't anyhow add fnc1 symbols to 'data'. Looks like it have to be put before, after or within process of matrix generation, but not in the data itself..
Just tested it

[DjDecent]

def data_matrix_special_character(char):

return chr(ord(char)-1)

FNC1 = data_matrix_special_character("\xf1") # codeword 232

data = FNC1 + "019781910050262"

this doesnt work.

You can't anyhow add fnc1 symbols to 'data'. Looks like it have to be put before, after or within process of matrix generation, but not in the data itself..

Just tested it

This definitely works I just did it

[xjpf]

from pystrich.datamatrix import DataMatrixEncoder
FNC1 = chr(ord('\xf1')-1) # codeword 232
inp = FNC1 + '0104603757996235215X09mURooMGUg�91EE10�92b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M='
print(inp)
encoder = DataMatrixEncoder(inp)
encoder.save( "datamatrix_test.png" )

ð0104603757996235215X09mURooMGUg�91EE10�92b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M=

Doesn't work

[DjDecent]

from pystrich.datamatrix import DataMatrixEncoder FNC1 = chr(ord('\xf1')-1) # codeword 232 inp = FNC1 + '0104603757996235215X09mURooMGUg�91EE10�92b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M=' print(inp) encoder = DataMatrixEncoder(inp) encoder.save( "datamatrix_test.png" )

ð0104603757996235215X09mURooMGUg�91EE10�92b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M=

Doesn't work

Make sure you are using char 29 between the AIs

[xjpf]

Make sure you are using char 29 between the AIs

What is AIs?
If you meant chr(29) symbols instead of � bytes, that doesn't help aswell

[DjDecent]

Application Identifiers
https://plznpg.onrender.com/ This is something I'm working on that uses pystrich to generate a GS1 DataMatrix

Use the ZPL below to generate your GS1 DataMatrix

^XA

^FT10,10^BXN,5,200,,,,_\n^FD_10104603757996235215X09mURooMGUg_191EE10_192b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M=^FS

^XZ

EDIT. Scanned value: (01) 04603757996235 (21) 5X09mURooMGUg (91) EE10 (92) b4wYepTreVa2N0cvArPX0n2LNc7MDs/B52dJFOAxl3M=

[xjpf]

Sir. Is this really how pyStrich works?
I have to go on some sites in internet, look for some strange symbol combinations(which is I still don't understand) and inject them manually directrly to each line?
And there is no way to do it "framework-way"?

[DjDecent]

Sir. Is this really how pyStrich works?
I have to go on some sites in internet, look for some strange symbol combinations(which is I still don't understand) and inject them manually directrly to each line?
And there is no way to do it "framework-way"?

This is a testing page for a project I built that relies on pyStrich to draw barcodes. Just showing that this will work if you get the formatting right.

[xjpf]

This is a testing page for a project I built that relies on pyStrich to draw barcodes. Just showing that this will work if you get the formatting right.

So you approve that pyStirch doesn't work "right way" by itself?
And you have own project that that will help to all FNC1 symbol?
Will you kindly share it?

All my codes is looks like this:

01046610395010722151eP4NHkeQJP!�91EE10�92wmYcQ3ujsJuaLP+5R/fw9je0SrM5QTsCr02uOMamQgI=
0104661039501072215GqgKFaB%aGY2�91EE10�92aAGGtkj+/MUXHbkhM29BrmlldlHtVdlvhwqeD9gvO/g=
0104661039501072215cuOUcEj/+W;=�91EE10�92aSQjemJJ0wdIfLFUMwGNS+v0PhK8hf0kCsn0Nlr7gDM=
And I'm looking towards framework that'll be able to add FNC1 at start and GS as separators

[DjDecent]

This is a testing page for a project I built that relies on pyStrich to draw barcodes. Just showing that this will work if you get the formatting right.

So you approve that pyStirch doesn't work "right way" by itself?
And you have own project that that will help to all FNC1 symbol?
Will you kindly share it?

All my codes is looks like this:

01046610395010722151eP4NHkeQJP!�91EE10�92wmYcQ3ujsJuaLP+5R/fw9je0SrM5QTsCr02uOMamQgI=
0104661039501072215GqgKFaB%aGY2�91EE10�92aAGGtkj+/MUXHbkhM29BrmlldlHtVdlvhwqeD9gvO/g=
0104661039501072215cuOUcEj/+W;=�91EE10�92aSQjemJJ0wdIfLFUMwGNS+v0PhK8hf0kCsn0Nlr7gDM=
And I'm looking towards framework that'll be able to add FNC1 at start and GS as separators

Just make sure the output you are sending pyStrich matches the GS1 Data: from the log on my app. That is a print statement right before sending the string to pyStrich.

[xjpf]

I'm sorry, and really appreciate your help.. but looks we are kinda speaking different languages..

I have a task, to add FNC1 symbol at start of a dataline and print datamatrix where scanners will detect FNC1 at start and GS as delimeters
GS part is currently working perfectly with \x1d mask
But FNC1 part is not that straightforward

Currently all my datalines is matching this pattern: '01046610395010722151eP4NHkeQJP!�91EE10�92wmYcQ3ujsJuaLP+5R/fw9je0SrM5QTsCr02uOMamQgI=' and have to contain FNC1 as leading symbol

What exaclty I need to do to add that FNC1 to thousands of different datamatrixes to print them?