I'm trying to create an application that detects all the QR Codes in my current camera frame, but am limited in that AVFoundation seems to only give me 4 QR Codes focused near the middle. Is it possible to detect more QR Codes simultaneously in one frame?
Code: pretty much this
Welcome!
It seems you can use Vision to detect all QR codes in an image.
From the docs of VNDetectBarcodesRequest:
By default, a barcode request first locates all barcodes in the input image, then analyzes each to decode payload.
(Note that even though it's named "barcodes", the symbologies also support QR.)
This tutorial might be helpful.
Related
The native AVFoundation QR code scanner just can't see a low-contrast QR code that I need to be able to scan. I know it's possible to scan the code though, because it works fine with WeChat's QR scanner.
How do I scan this QR code? Is there a way to adjust my AVCaptureSession to allow for lower-constrast QR codes? Is there a package I can use that would be better?
Try to set capture quality to high.
session.sessionPreset = .high
I got it working with Zbar. Super easy to use, too. Here's a tiny demo (Xcode 9.3 and Swift 4.1): https://github.com/philipshen/ZBar-Demo-Swift-4
The documentation and the header file does not contain any information related to support of 3D barcodes. However, explicitly mentions AVMetadataMachineReadableCodeObject supports one-dimensional and two-dimensional barcodes. Therefore, does anybody know 3D Barcodes are supported by AVFoundation ?
Supported QRCodes by AVFoundation are upce,code39,Code 39 mod 43,EAN-13,EAN-8,code93,code128,pdf417,Interleaved 2 of 5,ITF14,DataMatrix ,Aztec & All of them are 1d/2d .https://www.scandit.com/types-barcodes-choosing-right-barcode/
If we try to go into detail of 3d bar codes which are called Custom QR Codes, The bars in a 3D barcode are read by a scanner that reads the differences in the height of each line .http://www.qrcodestickers.org/qr-code-articles/3D-barcodes.html.
We have implemented a QRCode reading function in iOS using the AVCaptureSession class, as described nicely here:
https://github.com/HEmobile/ScanBarCode/tree/master/ScanBarCodes
https://developer.apple.com/library/ios/documentation/AVFoundation/Reference/AVCaptureSession_Class/
But one thing we notice... the QRCode has to be aligned exactly vertically or horizontally. Oblique angles such as 45 degress does not trigger a scan. This issue doesn't really google, which is surprising.
Our experiments with other QRcode reading apps indicate that this limitation does not exist. Perhaps/seemingly (presumably -- since the built-in function is new) these apps don't use AVCaptureSession.
Our question is, is this a sign that Apple's version of this function is not mature yet? Or is there some option to enable or improve this capability?
Thanks for any thoughts.
It seems you've written some sort of limitation in your code. Check out my github repo: https://github.com/alexekoren/qr-3d
It was built specifically for reading QR Codes at angles in a pretty way. I'm testing it now and it pulls at 30-45 degrees easily.
Here's the direct link for everything you'll need to make the scanner object that can present on a UIView: https://github.com/AlexEKoren/QR-3D/blob/master/Code%20Scanner/Scanner/CSScanner.m
It should work out of the box!
Currently i am using ZBAR reader for decoding the QR codes. It is working fine. The problem occurs when QR code is heavily populated. ZBAR takes some time to read the content and due to this delay, the camera is kept open which annoys some users. So is there any way to capture the QR code as image and store in local and decode the image of QR code from local. This will stop the camera immediately and user won't see the camera opened for a long time. Thanks in advance
You didn't say anything about platform or language, but the the answer is "yes". See these examples.
I have integrate the zxing lib for qr code decoding in blackberry with OS 6.
i want to know how small image can be read the QR code any possibility to read minimum small image.I have try this that it is not working for 2.5x2.5 cm image.
The device contains the 5 MP camera.
EDITED:i have check the using the default camera looking nice but in camera open by the zxing lib is not look great.so is there any way to change the quality of camera view.
Please provide me help me.
As well as the size of the code, you also need to factor in how far away the code is from the camera and whether the camera supports macro-focus mode.
I would suggest using a larger code.