microsoft / opencv

Open Source Computer Vision Library

OpenCV: Open Source Computer Vision Library

Resources

• Homepage: https://opencv.org
  • Courses: https://opencv.org/courses
• Docs: https://docs.opencv.org/master/
• Q&A forum: http://answers.opencv.org
• Issue tracking: https://github.com/opencv/opencv/issues
• Additional OpenCV functionality: https://github.com/opencv/opencv_contrib

Contributing

Please read the contribution guidelines before starting work on a pull request.

Summary of the guidelines:

• One pull request per issue;
• Choose the right base branch;
• Include tests and documentation;
• Clean up "oops" commits before submitting;
• Follow the coding style guide.

opencv's Issues

Contribute videoio maintenance update

A few refactoring changes simplifying inner structure of videoio for WinRT bits, comment improvements and overall code cleanup.

Related PR: #4047

Contribute WinRT video sample improved with face detection

Adding a UAP WinRT application able to detect human faces using OCV default Haar classifier.

Related commit: 3408114
Related PR: #4073

Backslash samples update

Because of current approach in samples *.props files OPENCV_WINRT_INSTALL_DIR environment variable requires trailing slash and samples fail to build in case there is no trailing slash.

Related PR: opencv#4075

WINRT imgcodecs decode_infinite_rowsperstrip failure

New test Imgcodecs_Tiff.decode_infinite_rowsperstrip fails on WINRT:
unknown file: error: SEH exception with code 0xc0000005 thrown in the test body.

Wrong initialisation of Mat in all your sample

Hi,

You inverted the height and the width when creating the cv::Mat on all your samples. Your sample works because Lena.png is a square image ^^

Thanks

Refactor ts CMakeLists.txt

Code

if(NOT WINRT)
  ocv_add_module(ts INTERNAL opencv_core opencv_imgproc opencv_imgcodecs opencv_videoio opencv_highgui)
else()
  ocv_add_module(ts INTERNAL opencv_core opencv_imgproc opencv_imgcodecs opencv_videoio)
endif()

can be optimized as

ocv_add_module(ts INTERNAL opencv_core opencv_imgproc opencv_imgcodecs opencv_videoio)
if(NOT WINRT)
  ocv_add_module(opencv_highgui)
endif()

however this causes build issues on Linux

WIN32: Debug opencv_test_ml crashes in ML_DTree.regression test

Debug version of opencv_test_ml crashes on the following output:
[ RUN ] ML_DTree.regression

The reason is _ITERATION_DEBUG_LEVEL 2 suppose performing of numerous checks. There is working with element outside of the vector bounds that is not checked by Release mode and may cause undefined behavior.

Callstack:

>   opencv_ml300d.dll!std::vector<int,std::allocator<int> >::operator[](unsigned int _Pos) Line 1201    C++
    opencv_ml300d.dll!cv::ml::DTreesImpl::addTree(const std::vector<int,std::allocator<int> > & sidx) Line 289  C++
    opencv_ml300d.dll!cv::ml::DTreesImpl::train(const cv::Ptr<cv::ml::TrainData> & trainData, int flags) Line 227   C++
    opencv_test_mld.exe!CV_MLBaseTest::train(int testCaseIdx) Line 440  C++
    opencv_test_mld.exe!CV_AMLTest::run_test_case(int testCaseIdx) Line 69  C++
    opencv_test_mld.exe!CV_MLBaseTest::run(int __formal) Line 257   C++
    opencv_test_mld.exe!cvtest::BaseTest::safe_run(int start_from) Line 221 C++
    opencv_test_mld.exe!ML_DTree_regression_Test::Body() Line 126   C++
    opencv_test_mld.exe!ML_DTree_regression_Test::TestBody() Line 126   C++
    opencv_test_mld.exe!testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test,void>(testing::Test * object, void (void) * method, const char * location) Line 3563    C++
    opencv_test_mld.exe!testing::internal::HandleExceptionsInMethodIfSupported<testing::Test,void>(testing::Test * object, void (void) * method, const char * location) Line 3614   C++
    opencv_test_mld.exe!testing::Test::Run() Line 3651  C++
    opencv_test_mld.exe!testing::TestInfo::Run() Line 3830  C++
    opencv_test_mld.exe!testing::TestCase::Run() Line 3945  C++
    opencv_test_mld.exe!testing::internal::UnitTestImpl::RunAllTests() Line 5824    C++
    opencv_test_mld.exe!testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl,bool>(testing::internal::UnitTestImpl * object, bool (void) * method, const char * location) Line 3563    C++
    opencv_test_mld.exe!testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl,bool>(testing::internal::UnitTestImpl * object, bool (void) * method, const char * location) Line 3614   C++
    opencv_test_mld.exe!testing::UnitTest::Run() Line 5437  C++
    opencv_test_mld.exe!RUN_ALL_TESTS() Line 20123  C++
    opencv_test_mld.exe!main(int argc, char * * argv) Line 3    C++

WINRT: perf tests failure

Command line:
opencv_perf_core.exe --perf_write_validation_results=some_file
Result:
unknown file: error: SEH exception with code 0xc0000005 thrown in auxiliary test code (environments or event listeners).
in the end of execution

Command line:
opencv_perf_core.exe --perf_read_validation_results=some_file
Fail:
Immediate app crash. Callstack:

    ntdll.dll!RtlpWaitOnCriticalSection()   Unknown
    ntdll.dll!RtlpEnterCriticalSectionContended�()  Unknown
    msvcp120_app.dll!std::basic_istream<char,struct std::char_traits<char> >::operator>>(float &)   Unknown
>   opencv_perf_imgproc.exe!loadPerfValidationResults(const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & fileName) Line 677   C++
    opencv_perf_imgproc.exe!perf::TestBase::Init(const std::vector<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,std::allocator<std::basic_string<char,std::char_traits<char>,std::allocator<char> > > > & availableImpls, int argc, const char * const * argv) Line 907 C++
    opencv_perf_imgproc.exe!main(int argc, char * * argv) Line 3    C++

Core_Matx.fromMat_ Windows 8.0 failure

Windows 8.0 has Core_Matx.fromMat_ test failure.

Initial check based on test-contrib branch.
Also reproduced on Windows 8.0 for Itseez master

Repro:

Itseez master

1. Generate projects for Visual Studio 2012 (cmake -G "Visual Studio 11 2012" <path to src> w/o additional parameters should be enough)
2. Build solution
3. Start opencv_test_core.exe. You may use parameter --gtest_filter=*fromMat_ to reduce execution time

test-contrib branch

1. Set all environment variables and install required tools from this readme
2. Run the following command from platforms\winrt to generate solution:
   setup_winrt.bat WS 8.0 x86 -G "Visual Studio 11 2012"
3. Build solution
4. Start opencv_test_core.exe. You may use parameter --gtest_filter=*fromMat_ to reduce execution time

Log:

[----------] 1 test from Core_Matx
[ RUN      ] Core_Matx.fromMat_
..\..\..\..\..\..\modules\core\test\test_mat.cpp(1217): error: Value of: 0.
  Actual: 0
Expected: norm(a, b, NORM_INF)
Which is: 13
[  FAILED  ] Core_Matx.fromMat_ (0 ms)
[----------] 1 test from Core_Matx (0 ms total)

Additional info:

 TEST(Core_Matx, fromMat_)
 {
     Mat_<double> a = (Mat_<double>(2,2) << 10, 11, 12, 13);
     cout << " MatA: " << a; // a is correct there
     Matx22d b(a);
     cout << " MatB: " << b; // b is [0, 0; 0, 0]
     ASSERT_EQ( norm(a, b, NORM_INF), 0.);
 }

Say, replacing of Matx22d b(a); with explicit initialization via pointer Matx22d b((double *)a.ptr()); makes the test pass. However I think this cannot be considered as fix because test checks work of the constructor b(a)

Install dir is incorrect for ARM builds

Install dir is incorrect for ARM builds. Builds are put in x86 dir instead of ARM. The x86 dir in the image below should be ARM.

Contribute concurrency support

Related PR-3840

OpenCV Image processing on WindowsPhone 8.1

Hi, i'm a student and currently develloping an Windows Phone 8.1 application to use on a nokia lumia 625. This application must be capable of capturing an image from the camera, process it to create a vector of KeyPoints and compare it to another image. The images will be very simple forms, so it won't use a lot of memory.

My problem is that all the examples i can find use the highgui's functions to load images (imread()), and cvLoadImage() doesn't seem to work either. I know now that the Highgui lib is not yet implemented, so my question is, is there a way to load and process images with the actual implementation ?

All of this will be wrapped in a c# application, so the capture part could be done there, but the processing part is still up to openCV.

Thank you in advance for your replys/advices.

Targeting issues to Phone 8.1

Hi there.

I just downloaded the repo from git and added all project references to my 8.1 phone app solution. they display as for 8.0 but offer no ability to retarget. this prevents me from adding references of these to my 8.1 project.

even after modifying the project files in notepad it doesnt help.

any ideas?

Mac unstable test

Log with this issue points at modules/stitching/perf/opencl/perf_stitch.cpp:140 for a failure of OCL_stitch_boat.boat test.

OCV folks mentioned this test fails sometimes.

Here is an example of a subsequent build log without any code changes.

This doesn't seem to be related to WinRT and is simply an unstable behavior of this specific test.

CMake generated WindowsStore 8.0 ARM core module missing ole32.lib

How to reproduce:

setup_winrt.bat ws 8.0 arm
build OpenCV.sln in bin/WS/8.0/ARM

core module generates the following error because linker input is missing ole32.lib.

1>------ Build started: Project: opencv_core, Configuration: Debug ARM ------
1>LINK : warning LNK4075: ignoring '/INCREMENTAL' due to '/OPT:ICF' specification
1> Creating library D:/GitHub/opencv/bin/WS/8.0/arm/lib/Debug/opencv_core300d.lib and object D:/GitHub/opencv/bin/WS/8.0/arm/lib/Debug/opencv_core300d.exp
1>system.obj : error LNK2019: unresolved external symbol __imp_CoCreateGuid referenced in function __unwind$4
1>D:\GitHub\opencv\bin\WS\8.0\arm\bin\Debug\opencv_core300d.dll : fatal error LNK1120: 1 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Updating OCV structure

cuda_test and ocl_test (and possible some other) files contain some macros and functions that are required for other tests. So these files are added even in case there is no CUDA and OpenCL support on the platform.

Contribute imgcodecs module

imgcodecs module contains logic that is in high demand e.g. cv::imread() and cv::imwrite()

Related feature request: #10
Related PR: #3892

WinRT and WP8 samples are using msvcr120.dll

A developer reports that the WinRT and WP8 samples are using msvcr120.dll. Make sure the apps pass the Windows App Certification tests.

Can't build test-vs2015 branch, error code: APPX1639

I'm getting the errors (44, specifically for all libs and test applications)

Severity Code Description Project File Line
Error APPX1639 File 'Microsoft.Windows.Build.Appx.AppxPackaging.dll.manifest' not found. See http://go.microsoft.com/fwlink/?prd=12560&pver=1.0&plcid=0x409&ar=MSDN&sar=PlatformMultiTargeting&o1=UAP&o2=10.0.10069.0 for more information. libjasper C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\AppxPackage\Microsoft.AppXPackage.Targets 765

But the link provided above doesn't seem to take me anywhere except the Microsoft home page and a google search fails to turn up anything related to either VS2015, Windows 10 Preview or OpenCV.

Any help is appreciated, thanks in advance!

Contribute highgui module dummy implementation

highgui module contains API for quick UI prototyping. It is also a dependency for tests contribution:

• local - #43
• itseez - #4064

This contribution is aiming to provide dummy implementation that would allow test run on winrt avoiding numerous macro-wrappers disabling highgui dependent code. That should unblock tests contribution referred above.

Subsequent contribution should actually enable highgui related logic for WinRT.

• Added dummy highgui WinRT implementation: 7810fda

Related PR: #4090

Contribute WinRT support

Backtracking initial contribution PR-3700

WINRT: opencv_test_photo crash

opencv_test_photo test suite crashes in the end of the execution. See details below (installation of dll symbols may be required):

Callstack:

    msvcr120.dll!_invoke_watson()   Unknown
    msvcr120.dll!_invalid_parameter()   Unknown
    msvcr120.dll!_invalid_parameter_noinfo()    Unknown
    msvcr120.dll!_close()   Unknown
    msvcr120.dll!_fclose_nolock()   Unknown
    msvcr120.dll!fclose()   Unknown
    msvcr120.dll!_fcloseall()   Unknown
    msvcr120.dll!__endstdio()   Unknown
    msvcr120.dll!_initterm()    Unknown
    msvcr120.dll!__crtdll_callstaticterminators()   Unknown
    msvcr120.dll!_CrtEndBoot()  Unknown
    ntdll.dll!LdrpCallInitRoutine() Unknown
    ntdll.dll!LdrShutdownProcess()  Unknown
    ntdll.dll!RtlExitUserProcess()  Unknown
    kernel32.dll!ExitProcessImplementation()    Unknown
>   opencv_test_photo.exe!__tmainCRTStartup() Line 643  C
    kernel32.dll!BaseThreadInitThunk()  Unknown
    ntdll.dll!RtlUserThreadStart()  Unknown

Exception details:

Unhandled exception at 0x00007FFBAF83DD27 (msvcr120.dll) in opencv_test_photo.exe: An invalid parameter was passed to a function that considers invalid parameters fatal.

File:
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\crt\src\crtexe.c
Line 643:

#if !defined (_WINMAIN_) && defined (_CRT_APP)

            _cexit();
            /* WINAPI_FAMILY_APP "Windows" applications should never reach here,
            * but Console applications will - if they do not exit the process first.
            * So, exit the process.
            */
>            ExitProcess(mainret);

Contribute Python script UNIX support update

This updates UNIX binaries to use relative RPATH to libraries and updates run.py to copy bin and lib folders to the same dir when performing --tests_move.

OSX support is not implemented because of technical difficulties. It looks like the most common for OSX is post build updating of the absolute paths on binaries.

Something like this should work (Checked manual way from there):

otool -l binary | grep -oE "[^ ]libopencv[^ ]*" | xargs -I % install_name_tool -change % @loader_path/../lib/<substitution of library name>

However it is difficult to get and substitute <substitution of library name> part in this command using OSX terminal utilities.

In case there are any ideas or suggestions on OSX, I can try to extend run.py move functionality for OSX too.

Undefined behavior in test

In case we entered this conditional block basing on !f condition, we get undefined behavior there as f is uninitialized

Q: Use of these libraries in Cordova or Xamarin built applications?

Is it possible to consume these libraries in either Cordova or Xamarin (to ease cross platform builds).

Thanks in advance!
//Adam

VS2015 x64 calib3d crash

Repro steps (Windows 10 Preview):

1. Install VS2015 CTP6 from there
2. Install Windows 10 SDK from there
3. Clone https://github.com/Microsoft/CMake.git
4. Checkout feature/Win10 branch
5. Build CMake for Windows
6. Clone https://github.com/MSOpenTech/opencv.git
7. Checkout test-vs2015 branch
8. Create "bin" directory and cd to it
9. Run command Path\To\New CMake\bin\Release\cmake.exe -G "Visual Studio 14 2015 Win64" -DCMAKE_SYSTEM_NAME:String=WindowsStore -DCMAKE_SYSTEM_VERSION:String="10.0" -DCMAKE_VS_EFFECTIVE_PLATFORMS:String=x64 -DCMAKE_INSTALL_PREFIX:PATH=C:\Users\ocv_install ..
10. Open solution, change configuration to Release and build it
11. Start opencv_test_calib3d

Expected: Full test pass
Actual: Crash in the fisheye.jacobians test

Reproduced for VS2015 CTP6 x64 solution only. Pass for VS2015 CTP6 x86, VS2013 x64, VS2013 x86

Pass for VS2015 x64 with this patch:

diff --git a/modules/core/src/rand.cpp b/modules/core/src/rand.cpp
index bd1d80c..39dcc02 100644
--- a/modules/core/src/rand.cpp
+++ b/modules/core/src/rand.cpp
@@ -634,8 +634,7 @@ void RNG::fill( InputOutputArray _mat, int disttype,
         }

         if( n1 < cn )
-            for( j = n1*esz; j < cn*esz; j++ )
-                mean[j] = mean[j - n1*esz];
+            mean = mean + n1 * esz;

         if( _param2.isContinuous() && _param2.type() == ptype )
             stddev = _param2.ptr();
@@ -647,8 +646,7 @@ void RNG::fill( InputOutputArray _mat, int disttype,
         }

         if( n1 < cn )
-            for( j = n1*esz; j < cn*esz; j++ )
-                stddev[j] = stddev[j - n1*esz];
+            stddev = stddev + n1 * esz;

         stdmtx = _param2.rows == cn && _param2.cols == cn;
         scaleFunc = randnScaleTab[depth];

Contribute WinRT test support

Adding test support for Windows RT.
Some unused highgui #include's were removed (sample)
Instructions on building and running tests for WinRT are in platforms/winrt/readme.txt

NOTE: Tests are not supposed to run on real ARM devices in this contribution. Please use Windows 8.0 or Windows 8.1 PC to run tests.

Test results for Windows 8.0 VS2012 and Windows 8.1 VS2013 are there

Building OpenCV on WIndows Phone 8.0

Thank you for the effort on the opencv build.
However, I couldn't build it successfully.
Since I am building on WIndows Phone 8.0, I skip the step: "How to build OpenCV for WinRT".
And when I got to step 3 on "How to setup CMake GUI to build the WinRT Projects", I selected only the options mentioned on README.md.
After that error appears on step 5 saying that it could not load "cudev.lib", and "core300.lib".
I am doing all these on visual studio 2012 on windows 8.
It would be very helpful if you can give me a hand on this one. Thank you

WIN32: opencv_test_imgproc x86 version fails

Repro steps:

1. Clone https://github.com/Itseez/opencv
2. Open CMake UI
3. Click Configure and choose Visual Studio 12 2013 as generator
4. Build opencv_test_imgproc
5. Run opencv_test_imgproc(d).exe
6. Expected: all tests pass; Actual: Imgproc_Hist_MinMaxVal.accuracy failed

Note: All tests pass for Visual Studio 12 2013 Win64 generator

Adding references to WP8.0 project

I’m trying to use the OpenCV dlls in a Windows Phone 8.0 project.

I built the solution at binWP8 folder by targeting ARM. However when I try to add dlls as a reference to WP8.0 project, I get below error message:
“A reference to a higher version or incompatible assembly cannot be added to the project”

Is this this the correct way of adding the references to a new WP8.0 project or should I do something else before hand? Thanks.

x64 arc is an available option in setup_winrt.bat but is not actually supported

setup_winrt.bat -h

 architecture - Array of target architectures to build for.
             Default: x86
             Example: 'ARM,x64'
             Options: x86, ARM, x64. Available options may be limited depending on your local setup.

Readme file does not mention x64 as we don't support it.

Should make setup_winrt.bat options consistent with readme file: either remove x64 option from setup_winrt.bat or make a note in readme that x64 only works for WS platform and not for WP.

Support for other modules

Hello , are there any plans in the future to support other modules for windows phone ( highgui, contrib, ...) ?
Thanks for reply.

WINRT: opencv_test_photo failures

The following tests in opencv_test_photo test suite fail with the similar exception:

Photo_MergeMertens.regression
Photo_MergeDebevec.regression
Photo_MergeRobertson.regression
Photo_CalibrateDebevec.regression
Photo_CalibrateRobertson.regression

Exception: unknown file: error: SEH exception with code 0xc0000005 thrown in the test body.

Support for Windows Universal Apps

Thanks for cool opencv port!

1 week ago, Visual Studio 2013 Update 2 was released which include "Universal App" support. It contains unification API of WP8 and WinRT.

Is this opencv lib support Universal App?

WINRT: opencv_test_video failure

Test Video_calcOpticalFlowDual_TVL1.Regression from opencv_test_video test suite fails with the following exception:
Exception: unknown file: error: SEH exception with code 0xc0000005 thrown in the test body.

Contribute WinRT linker issue fix (remove vfw32.lib)

Related PR: opencv#3863

CMake requires Windows Desktop SDK / Windows Phone '8.0' SDK

Hi there,

I'm attempting to build OpenCV but coming across this error. I'm pretty sure I have the SDK's installed, in fact I have the enterprise edition of Visual Studio 2015 RC installed. I checked for the SDK folders and they are there, plus I can obviously build for both phone and desktop in the IDE.

Any idea how to resolve this issue? Maybe it isn't compatible with 2015 yet?

---

cd opencv/platforms/winrt
setup_winrt.bat "WP,WS" "8.0,8.1" "x86,ARM" -b

---

Security warning
Run only scripts that you trust. While scripts from the internet can be useful,
this script can potentially harm your computer. If you trust this script, use
the Unblock-File cmdlet to allow the script to run without this warning
message. Do you want to run
C:\bob\opencv-master\opencv-master\platforms\winrt\setup_winrt.ps1?
[D] Do not run [R] Run once [S] Suspend [?] Help (default is "D"): R
DEBUG> Input Platforms: WP,WS
DEBUG> WP is valid
DEBUG> WS is valid
DEBUG> Processed Platforms: WP WS
DEBUG> Input Versions: 8.0,8.1
DEBUG> 8.0 is valid
DEBUG> 8.1 is valid
DEBUG> Processed Versions: 8.0 8.1
DEBUG> Input Architectures: x86,ARM
DEBUG> x86 is valid
DEBUG> ARM is valid
DEBUG> Processed Architectures: x86 ARM
INFO> -----------------------------------------------
INFO> Target:
INFO> Directory: C:\bob\opencv-master\opencv-master\bin\WP\8.0\x86
INFO> Platform: WindowsPhone
INFO> Version: 8.0
INFO> Architecture: x86
INFO> Generator: Visual Studio 12 2013
INFO> Install Directory: C:\bob\opencv-master\opencv-master\bin\insta
ll\WP\8.0\x86

Directory: C:\bob\opencv-master\opencv-master\bin\WP\8.0

Mode LastWriteTime Length Name

---

d---- 26/05/2015 16:46 x86
INFO> Generating project:
INFO> cmake -G Visual Studio 12 2013 -DCMAKE_SYSTEM_NAME:String=WindowsPhone -DC
MAKE_SYSTEM_VERSION:String=8.0 -DCMAKE_VS_EFFECTIVE_PLATFORMS:String=x86 -DCMAKE
_INSTALL_PREFIX:PATH=C:\bob\opencv-master\opencv-master\bin\install\WP\8.
0\x86 C:\bob\opencv-master\opencv-master
CMake Error at CMakeLists.txt:88 (project):
A Windows Phone component with CMake requires both the Windows Desktop SDK
as well as the Windows Phone '8.0' SDK. Please make sure that you have
both installed

-- Configuring incomplete, errors occurred!
See also "C:/bob/opencv-master/opencv-master/bin/WP/8.0/x86/CMakeFiles/CM
akeOutput.log".
INFO> -----------------------------------------------
INFO> Building and installing project:
INFO> Executing: msbuild OpenCV.sln /p:Configuration='Debug' /m
Microsoft (R) Build Engine version 12.0.31010.0
[Microsoft .NET Framework, version 4.0.30319.0]
Copyright (C) Microsoft Corporation. All rights reserved.

MSBUILD : error MSB1009: Project file does not exist.
Switch: OpenCV.sln
INFO> Error: Failure executing command: msbuild OpenCV.sln /p:Configuration='Deb
ug' /m

WINRT: Windows 8.0 build issue

Windows 8.0 fails to build w/ tests:

File: ts_perf.cpp
Line: 1239, Sleep(perf_validation_idle_delay_ms);

Sleep is unsupported on Windows 8.0 and is supported on 8.1;
Need to find a replacement and use it on Windows 8.0 (or remove this for 8.0 if possible w/o additional issues)

Contribute WinRT face detection sample

Adding a sample WinRT modern desktop application able to detect human faces using OCV default Haar classifier. Sample was created by @ericmitt.

Related commit: c6875d8
Related PR: #4069

Contribute Python script update

Related PR: opencv#3887

Request for sample Winmd component

Hi,
It would really help us .Net developers with minimal working experience of C++/CX to have a sample that shows how to create Winmd components to cover a tiny surface area of OpenCV. This would enable us to do our own winmd components for the functionality we need in OpenCV.

e.g. Facedetection sample would be a great candidate.

1. Load image into an XAML control in the C# project.
2. Pass image data/buffer on through the winmd component to OpenCV to run face detection
   3a. Get back detection results from winmd into C# calling code - so caller can decide how to present that info i.e. put squares in XAML over detected regions
   3b. Get back processed image data/buffer from Winmd component - with the detected "squares" on it AND then set that data/buffer as source of the XAML image control

I think this would really help us create our own Winmd components so we can still do as much as possible in .Net while reach out to teh performant C++/CX for OpenCV.

Contribute JavaScript sample

Related PR-3841

Cannot release camera

Could you please show me how the AppMain::stop() method in the wintry_universal/VideoCapture could be implemented in a way that actually makes the code re-entrant on Windows Phone 8.1?

Everything we tried resulted in the camera being locked (and / or the App freezes as soon as the CaptureFrameGrabber destructor calls (void)_capture->StopPreviewAsync()). If the MediaCapture object is not disposed, it is necessary to reset the Windows Phone before either our App or other Apps (like the Camera App) can use the camera again.

It is very cool to have this OpenCV port, but not being able to release the camera correctly sadly makes it impossible to release an Windows Phone 8.1 App based on this library.

Optimization on Windows Phone (e.g. Lumia 920)

We develop an SDK for road sign recognition on Windows Phone. It is a port from iOS and Android. Performance on e.g. a Lumia 920 is not so good at the moment. Will there be optimization efforts of OpenCV for Windows Phone planned that will improve performance? Also, what can we do/investigate to improve our classifier on Windows Phone at the moment?

Contribute ml accuracy tests fix

Branch doesn't align with RPI2/IoT instructions on blog

Trying to generate/find RPI2 binaries for Windows 10 IoT development however the blog post on the matter is misaligned with the git repo.

https://msopentech.com/blog/2015/05/15/uap-in-action-running-opencv-on-raspberry-pi-ii/

Contribute videoio module

videoio module contains video handling logic that has been migrated from highgui module in OCV 3.0

• Moved old wrappers: 54526f8
• Added WinRT support for videoio: 4262567
• Added configuration changes: 5845726
• Added sample Windows Universal application: 7b34ebe

Related PR: #4005

Use new License headers

Switch from

Copyright © Microsoft Open Technologies, Inc.
All Rights Reserved
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
...

to

Copyright (c) Microsoft Open Technologies, Inc. 
All rights reserved.

(3-clause BSD License)

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
...

CC @qjhd554 Adalberto

Update README to mention -b flag

Current readme does not mention that script should be invoked with -b flag to build and install all binaries and includes. This is required for the samples to make them work. Should add this and contribute.

Removing unused winrttest.cpp file

Related PR: opencv#3864