it is quite stranger that the libary can't scan this qrcode

[pppaulpeter]

when i run the qrtest, the library can't detect the qrcode in the image, idon't know the reason, it seems the qrcode is quite clear.

[dlbeer]

On Thu, Jul 15, 2021 at 02:59:36PM -0700, pppaulpeter wrote: when i run the qrtest, the library can't detect the qrcode in the image, idon't know the reason, it seems the qrcode is quite clear. 

It looks like the rightmost column of the QR code has been cropped off, and the finder patterns don't like like they're in the correct proportion (the rings are very thin).

…

-- Daniel Beer ***@***.***> http://dlbeer.co.nz/ PGP: BA6E 0B26 1F89 246C E3F3 C910 1E58 C43A 160A 553B

[pppaulpeter]

Hi
thanks for explain. but i scan this image by my iphone. and this is the orignal image, by the library i still can't get a result. maybe the reason is the distortion? do i need distortion correction before call the api?
home/qrtest /home/qr
qrcode_three.png qrtest

/home/qrtest /home/qrcode_three.png

quirc test program
Copyright (C) 2010-2012 Daniel Beer [email protected]
Library version: 1.0

                                      Time (ms)       Count

Filename Load ID Total ID Dec

qrcode_three.png : 27 1387 1428 6 0

[dlbeer]

On Fri, Jul 16, 2021 at 01:02:34AM -0700, pppaulpeter wrote: thanks for explain. but i scan this image by my iphone. and this is the orignal image, by the library i still can't get a result. maybe the reason is the distortion? do i need distortion correction before call the api?

Do you mean that the iPhone is able to decode the QR code from that image? I tried a couple of online decoders (including ZXing) and they couldn't manage it either. I think distortion is part of the problem, but also the missing cells. Cheers, Daniel

…

-- Daniel Beer ***@***.***> http://dlbeer.co.nz/ PGP: BA6E 0B26 1F89 246C E3F3 C910 1E58 C43A 160A 553B

[pppaulpeter]

On Fri, Jul 16, 2021 at 01:02:34AM -0700, pppaulpeter wrote: thanks for explain. but i scan this image by my iphone. and this is the orignal image, by the library i still can't get a result. maybe the reason is the distortion? do i need distortion correction before call the api?
Do you mean that the iPhone is able to decode the QR code from that image? I tried a couple of online decoders (including ZXing) and they couldn't manage it either. I think distortion is part of the problem, but also the missing cells. Cheers, Daniel
…
-- Daniel Beer @.***> http://dlbeer.co.nz/ PGP: BA6E 0B26 1F89 246C E3F3 C910 1E58 C43A 160A 553B

yes, iphone could decode that QR code.
Do you know the reason why quirc could just detect the qr code in the orignal image, but can't decode them?
this is the log output:

# /home/qrtest /home/qrcode_three.png
_quirc test program
Copyright (C) 2010-2012 Daniel Beer [email protected]
Library version: 1.0

                                      Time (ms)       Count

Filename Load ID Total ID Dec
-------------------------------------------------------------------------------_
qrcode_three.png : 27 1387 1428 6 0

[dlbeer]

On Tue, Jul 20, 2021 at 08:23:18AM -0700, pppaulpeter wrote: > On Fri, Jul 16, 2021 at 01:02:34AM -0700, pppaulpeter wrote: thanks for explain. but i scan this image by my iphone. and this is the orignal image, by the library i still can't get a result. maybe the reason is the distortion? do i need distortion correction before call the api? > Do you mean that the iPhone is able to decode the QR code from that image? I tried a couple of online decoders (including ZXing) and they couldn't manage it either. I think distortion is part of the problem, but also the missing cells. Cheers, Daniel > […](#) > -- Daniel Beer ***@***.***> http://dlbeer.co.nz/ PGP: BA6E 0B26 1F89 246C E3F3 C910 1E58 C43A 160A 553B yes, iphone could decode that QR code. Do you know the reason why quirc could just detect the qr code in the orignal image, but can't decode them? this is the log output:

If you have a look at the image with the "inspect" tool, it looks like the image is distorted in a way that can't be undone with the perspective transform that quirc uses.

…

-- Daniel Beer ***@***.***> http://dlbeer.co.nz/ PGP: BA6E 0B26 1F89 246C E3F3 C910 1E58 C43A 160A 553B

[numberone0001]

Hi，I also met the same problem. When I trying to detect the QR code below, it can not work through "quric". But other algorithms work perfectly, Such as the Wechat QR detect.
![200]

[numberone0001]

Or you can use this online detect: https://cli.im/deqr. They also can show the results.