wechat_qrcode exception

[zhanglaplace]

System information (version)

• OpenCV => 4.2
• Operating System / Platform => Ubuntu16.04
• Compiler => g++

Detailed description

qrcode decode image get a Segmentation Fault
received signal SIGSEGV, Segmentation fault. （double free or corruption (out)）
#0 0x00005555555949db in zxing::UnicomBlock::Bfs(int, int) ()
#1 0x0000555555594b09 in zxing::UnicomBlock::GetUnicomBlockIndex(int, int) ()
#2 0x00005555555b684f in zxing::qrcode::FinderPatternFinder::find(zxing::DecodeHints const&, zxing::ErrorHandler&) ()
#3 0x00005555555a1fd3 in zxing::qrcode::Detector::detect(zxing::DecodeHints const&, zxing::ErrorHandler&) ()
#4 0x00005555555ba32d in zxing::qrcode::QRCodeReader::decodeMore(zxing::Refzxing::BinaryBitmap, zxing::Refzxing::BitMatrix, zxing::DecodeHints, zxing::ErrorHandler&) ()
#5 0x00005555555bc7a1 in zxing::qrcode::QRCodeReader::decode(zxing::Refzxing::BinaryBitmap, zxing::DecodeHints) ()
#6 0x00005555555797e4 in cv::wechat_qrcode::DecoderMgr::Decode(zxing::Refzxing::BinaryBitmap, zxing::DecodeHints) ()
#7 0x0000555555579984 in cv::wechat_qrcode::DecoderMgr::TryDecode(zxing::Refzxing::LuminanceSource, zxing::Refzxing::Result&) ()
#8 0x0000555555579e37 in cv::wechat_qrcode::DecoderMgr::decodeImage(cv::Mat, bool, std::__cxx11::basic_string<char, std::char_traits, std::allocator >&) ()

Steps to reproduce

Issue submission checklist

• I report the issue, it's not a question
• I checked the problem with documentation, FAQ, open issues,
  answers.opencv.org, Stack Overflow, etc and have not found solution
• I updated to latest OpenCV version and the issue is still there
• There is reproducer code and related data files: videos, images, onnx, etc

[alalek]

Please provide complete minimal reproducer including used flags and input image

/cc @dddzg

[zhanglaplace]

@alalek decode will be failed when detect output boundingbox is big enough, such as 1024x1024;

[dddzg]

Could you please try some images and check whether it only happens for the image with a big bounding box?

[DoubleHeartLi]

I also have this problem, whether there is a solution or whether the reason has been found? thanks
I use wechat_qrcode in iOS, the detailed description is the same as mine.

[MichaelHuyp]

same issue... Has the latest version been resolved?

[dddzg]

I am not clear about how to reimplement this bug.
Did it only happen when the input image is large?

[Channingss]

I ran into a similar problem, and the stack of errors reported was almost the same
遇到类似的问题，报错的堆栈几乎一致。

[Channingss]

@alalek decode will be failed when detect output boundingbox is big enough, such as 1024x1024;

@zhanglaplace

When the boundingbox is too large, does the bug appear occasionally or must go wrong?

[MichaelHuyp]

My side is the daily scan code image that occasionally crashes. So far, I haven’t found the regularity of the crash image.

[MichaelHuyp]

崩溃标识 mach
崩溃类型 EXC_BAD_ACCESS (SIGSEGV)
崩溃子类型 KERN_INVALID_ADDRESS
崩溃地址 0x000000014541c000
崩溃诊断 Attempted to dereference garbage pointer 0x14541c000.Originated at or in a subcall of unknown, cannot find symbol
It is a decode image executed in a multi-threaded environment, I don't know if it is related to thread safety

[wxyjevol]

the same issue..
i found that scan code when i cover the camera with hand is easier to happen.
ps. my device is Huawei P20

在我的华为P20上用手半捂住摄像头扫描时比较容易出现

[alalek]

Use imwrite(.png) to save the last frame before crash.
After that try to prepare complete minimal reproducer (including the image).

[Channingss]

@dddzg

When the hand is not completely covered, the above errors will occasionally occur.

it's strange, under the above circumstances, the QR code detection model will predict large bbox。