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Questions tagged [qr-code]

QR code is an ISO-standardized two-dimensional barcode format.

Here is a sample QR-Code, pointing to Tag wiki qr-code

Simple QR Code

A Qr-code decoder has many specific patterns to recognize how to read the QR-code

Eyes

Eyes Qr code

Alignment

Alignment

Timing

Timing

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Addition and multiplication in a Galois Field

I am attempting to generate QR codes on an extremely limited embedded platform. Everything in the specification seems fairly straightforward except for generating the error correction codewords. I have looked at a bunch of existing implementations,…
captncraig
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How to locate QR code in large image to improve decoding performance?

Background I need to detect and decode a relatively small QR code (110x110 pixels) in a large image (2500x2000) on a Raspberry Pi. The QR code can be at any location in the frame, but the orientation is expected to be normal, i.e. top-up. We are…
Jens Ehrich
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Deprecation of Google Infographics, QR Codes

For the last 5 or so years if I have needed a QR code I have used the google APIs, yesterday for around 4 hours this service stopped. On investigation I found the service is now deprecated and a link to use Google Charts instead? I can not find any…
RickWeb
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Android cameraSource.stop() causing app to freeze

I am building an app that has a qr scanner using the google vision api. I am having trouble stopping the camera after the qr code is read. the flow is MainActivity -> QrActivity once the qr-code received a detection the app should return to the main…
Lonergan6275
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How to generate QR code with logo inside it?

I am developing the application for Android devices. I want to generate QR code with logo inside it. With ZXing I know how to generate simple QR codes like this one: But I want to generate QR code with logo inside it. So I want to get something…
Huitarheroherohero
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QR code scan from image file

Tried to use several libraries like ZXing, ZBar and their forks but didn't find way to scan barcode not from camera but from file. Can someone point me to right direction? Preferably I'm looking into ZXing: how to scan image from file (not from…
Barmaley
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printing QR codes through an ESC/POS thermal printer?

I'm printing some QR codes (from a Ruby script) writing ESC/POS commands to a Epson TM-T20 thermal printer. BTW, I'm writing a simple ESC/POS commands printer "driver". The printer I'm using an Epson TM-T20 (USB interface) I'm doing some tests from…
Giorgio Robino
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ZBar vs. zxing - QR recognition comparison

Can anyone tell which library is better in small QR Codes recognition under low lighting conditions? Platform is iPhone 4/iOS 5 I tried both Barcodes (zxing) and the ZBar apps and it seems that zxing was noticeably better in recognizing the codes…
atyachin
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javascript API for generating QR codes

I am looking for a javascript API for generating QR codes (name, address and such) and outputting them in a printable format (png/jpeg/pdf). This seems to me to be something others before must have had a need for.
lmkk
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Why is the camera preview rotated by 90 degrees in the Android emulator?

I have attached the webcam to the emulator and I always see the camera rotated by 90 degrees. What I did is simply to set "Webcam0" as the device to be used as the rear camera in the emulator. Background: I'm trying to fix an issue with an app I'm…
Giordano
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phpexcel insert qrcode into excel and save it to client end

I was trying to export data to excel file with a QRcode within a cell. I googled up and tried for clue. Finally thought with adding a sample image file. then after with a phpqrcode image file. It is still not succeeded can you please help me…
Jimson Jose
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Read qrcode from a web page with camera.

Im looking for a solution to read a QRCode on a webpage. Lets say I've generated with PHP and some library (zxing or something else) a QRCode and its printed on a piece of paper, ok? What i would like to do now, is to read it back with…
Sclerato
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Analyze partial or corrupted QR codes

How can I analyze broken/partial QR codes? Normally a QR decoder will just tell you that the data can not be read. This is not very useful. Even though the code is not readable, some information can, presumably, be extracted! Is the finder patterns…
hpekristiansen
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QR codes Limits

I have to generate codes with custom fields: id of field+name of field+values of the field. How long is the data I can encode inside the QRcode? I need to know how many fields\values I can insert. Should I use XML or JSON or CSV? What is most…
Bobo2012
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Change QR Scanner orientation with ZXING in Android Studio

I hope you can help me with this. Im using the Zxing Embedded Library in order to use the QR scanner, the problem is that is on Landscape mode and I would like to change it to Portrait. I have this on the dependencies of my Graddle compile…
Matías Gaete
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