Android Question How can I select encryption level in "QRGenerator.bas (V1.60)"

[I.Härter]

Hello everyone,

I dont know, if I'm only blind or dumb or if my problem is a real bug.
I'm in my really first B4A project, so I must ask a question, someone else would say: It's so simple!
I'm sorry.

I have a problem with QRGenerator.bas (V1.60).

[B4X] QRGenerator - Cross platform QR code generator

QRGenerator is a class that generates QR codes. It is written in B4X and it is compatible with B4A, B4i and B4J. iPhone default camera app recognizing the QR code displayed in a B4A app: Can create codes made of up to 2953 bytes. It depends on XUI library and B4XCollections v1.50+. It uses...

www.b4x.com

[B4X] QRGenerator - Cross platform QR code generator (Version 1 LMQH to Version 40 LMQH in post #11)

This is based on @Erel's posting here: https://www.b4x.com/android/forum/threads/b4x-qrgenerator-cross-platform-qr-code-generator.93092/ Have added all the required generator polynomial factors that are required for Version 1 to Version 40 QR Codes Changed the names of the array holding the...

www.b4x.com

How I can select a specific encryption level (L,M,Q or H)?

With every try I only get a "Level L" in different byte-length.
The same works in the example projects: Everytime only Level L.

I've made some tries to find the problem and a solution:
- found nothing in forum
- found nothing in source code, but
- manually resort the source code made me able to get one(!) other encryption level
- analysed the sub "Create" and think there are 2 problems:

1. No parameter for select the encryption level
2. The first search-loop in this sub everytime automatically equals first with a Level L encryption (based on predefined sort).

I've tried to rewrite these 2 steps with my simple knowledge and really: Now I get a 40H ...
... evertime! shit! That's not, what I want. So I must revert back to the original code.

How is the solution for select a specific encryption level?

 

[Erel]

The answer is very simple: there is no encryption involved with QR.
The letters describe the error correction level.

 

[I.Härter]

Hi Erel,

thank you for fast reply.
Please excuse my mis-translation.
I know there is no encryption.

What I mean:
How can I manually select a specific error correction level?

PS: Can I edit the Headline and my post after replies?

 

[Erel]

Why do you need to select it yourself???

Check the code it is very simple to see how it selects the version:

For Each version As QRVersionData In versions
        If version.MaxUsableSize >= Bytes.Length Then
            vd = version
            Exit
        End If
    Next

It selects the first version that can handle the input text size.

 

[I.Härter]

I know this code and i see, that this code never gets another ecc than Level L.
"the first version that can handle the input text size" is everytime only Level L.
Examples work too only with Level L.
So it seems Level M,Q and H are never used.
problem is the predefined sorting order in

Public Sub Initialize (BitmapSize As Int)

I've tried to do some changes (see my first post), but nothing works.
I can force some single solution by resort the definitions, but thats not the correct solution.
Otherwise I tried to expand the Sub Create to

Public Sub Create(Text As String, Level As Char) As B4XBitmap

and implement a handling code, but I'm not a Professional and it didn't work.

For Logo-Overlay the ecc must be selectable.
As I know from other codings/languages select or define a needed ecc level is the normal handling, but here i can do nothing.

 

[Erel]

Public Sub Create(Text As String, ErrorLevel As String) As B4XBitmap
    Dim vd As QRVersionData
    For Each version As QRVersionData In versions
        If version.MaxUsableSize >= Bytes.Length AND version.VersionName.EndsWith(ErrorLevel) Then
            vd = version
            Exit
        End If
    Next

 

[I.Härter]

Omg! I was only a sign beside ... Thank you Erel!