Qrcode is not interpretable

[MPast.1]

Hi everybody,

I'm trying to implement into a custom board, the dynamic Qrcode generation algorithm.

I'm using touchgfx 4.23.0, an SPI display with partial buffer strategy.

I would like to draw the string "https://support.touchgfx.com" . Display seem to draw it correctly but when I'm try to read it using my phone, this one is not readle. it seems not valid..

I'm using the following initialization sequence:

void Screen_QrCodeView::setupScreen()
{
Screen_QrCodeViewBase::setupScreen();

QR *code;

sprintf( string, "https://support.touchgfx.com");
code = new QR( string );

qrCode.setXY(10,10);
qrCode.setQRCode(code);
qrCode.setScale(8);
add(qrCode);
}

display screenQrcode detail

I don't understand the reason. If I change the size of QrCode using qrCode.setScale the result is the same.

Is it possibile to change the resoltuion of the QrCode? Is the QrCode resolution too poor respect the modern APP algorithm?

Does someone ahs the same issue? Please, Can someone try to draw the string https://support.touchgfx.com and share the picture for a comparison, ?

What can I check in the project?

Thanks to all

[Pavel A.]

[MPast.1]

Why your Qrcode is so different?

Can you share your sources files, you use in the project?

Thanks

[Andrew Neil]

---

@MPast.1 wrote:

Display seem to draw it correctly

---

What makes you say that?

It's drawn something - but, clearly, what it's drawn is not correct!

There's a lot of "tearing" in your image:

Can you correctly draw any other text as a QR code?

sprintf( string, "https://support.touchgfx.com");
code = new QR( string );

You haven't shown the definition of string

What if you just do

code = new QR( "https://support.touchgfx.com" );

[Andrew Neil]

---

@MPast.1 wrote:

Why your Qrcode is so different?

---

Indeed it's very different:

Apart from the "tearing", yours seems to be missing a lot of points

[MPast.1]

I know that is present a little tearing on Qrcode: i saw it and and I'm trying to understand if is QrCode sources files can be the cause.

At the moment I dont think its a big problem because Qrcode is technology has bits corrections so a little noise on the picture should not be a problem. (you imaging if a qrcode printed on a metalized label could be a little bit scratched. Your App always read it without "any" problem). The real problem is that Qrcode has a lot of missing dots.

I'm working without any optimization on code, but I don't think this is the problem

all the images and texts I'm using are drawn correctly

[Andrew Neil]

---

@MPast.1 wrote:

I dont think its a big problem because Qrcode is technology has bits corrections so a little noise on the picture should not be a problemtly

---

Exactly. So this shows that there's not just a small error in your QR code display - it is very wrong!

Probably it's a symptom of what's going wrong in creating the QR code - rather than the cause of not reading it?

Again: 

• Can you correctly draw any other text as a QR code?
  • other URLs ?
  • things that aren't URLs?
    
    
• Have you checked the definition of string
• Have you tried specifying the string as a literal directly in the constructor?

[Andrew Neil]

This site gives what looks like the same result as @Pavel A. 

https://www.qr-code-generator.com/ 

[Pavel A.]

@MPast.1 sorry cannot provide source. Just used a QR utility on my phone and checked that generated picture is recognized.

[MPast.1]

main screen

As you can see an example of correct scren with buttons, text and images.

String as decalred like "char"

QRCodeWidget qrCode;
char string[50];

Can be depend by display orientation?