Is it possible to set ECI header (encoding hint) when using BYTE mode about qr-code-generator

[nayuki]

Hi amvtek, thank you for the feedback. I understand the problem you are describing.

My library has currently no support for ECI, but I can add it sometime this week. I had no idea this niche feature had real-world usage. Please provide examples of good QR Codes for your application in mind, so that I can check my upcoming work.

For JavaScript, I am thinking of designing the API such that your code would look something like this:

var bytes = [3, 0, 9, 81, 255];
var eciAssignment = 31337;
var segments = [qrcodegen.QrSegment.makeEci(eciAssignment), qrcodegen.QrSegment.makeBytes(bytes)];
var qr = qrcodegen.QrCode.encodeSegments(segments, qrcodegen.QrCode.Ecc.LOW);

[amvtek]

Hello Nayuki,

thank you for your feedback.

Our QR codes contain cryptographic public key information, you can have a look here to get a feel of what use cases we are trying to enable https://www.amvtek.com/projects/kerpass-ust/

For test purpose we are using [255, 254, 253, ...0] repeated 2 times ( 512 bytes is maximum payload size in this project. For now we are using NUMERIC mode to encode bytes by group of 6 ( 12 hexa digits --> 15 decimal digits). This allow using capacity better than with base64 in the case of QR.

Your support is greatly appreciated, I will let you know if adding ECI segment allow binary to be decoded successfully by machine vision library.

Bests regards,
Marc

[nayuki]

Okay. Can you show examples of QR codes with ECI that scan successfully, along with their input description? I want to be able to replicate them exactly to the bit.

[amvtek]

Hello Nayuki,

for now on our side we haven't had the opportunity to attend scanning a barcode containing an ECI segment. Our assumption that it could solve problem decoding BYTE QrCode with google machine vision library come from here http://stackoverflow.com/questions/38398840/qr-codes-raw-binary-data/38506751

The person who reported to stackoverflow claims he managed to insert an ECI header using libqrencode. I looked there and ECI support is unclear as the doc claims that library does not currently support it.

The only encoder I found that appears to have partial support for ECI appears to be the zxing one, see here https://github.com/zxing/zxing/blob/master/core/src/main/java/com/google/zxing/qrcode/encoder/Encoder.java . I will try later on on my side to generate some barcode with ECI using zxing or your code after modification.

Best regards,
Marc

[nayuki]

Oh I see. I think I know what is going on now. Give me a bit of time to implement and validate some new code. In the meantime, a donation to Project Nayuki would be appreciated!

[amvtek]

OK Nayuki,
I will look to your suggestion.

Bests,
Marc

[nayuki]

ECI segment functionality has been added. Please try out the new API and see if it produces QR Codes that work correctly in your application.

[amvtek]

Hello,
we tested on our side and it worked

We used 1 as ECI segment value when encoding which apparently corresponds to ISO-8859-1.
Thank you very much for this, I think we shall mention this somewhere, as potentially zxing & machine vision barcode reading libraries won't let you recover encoded binaries without such segment

Bests,
Marc