feat: add conditional inclusion support to header parser by VadimLevin · Pull Request #27325 · opencv/opencv

VadimLevin · 2025-05-16T10:13:56Z

Brings support for conditional inclusion directives evaluation and proper #if/#else/#elif branches support.

Generated diffs are attached:

cv::Feature2D has a valid base class now, because #else is not discarded

#ifdef __EMSCRIPTEN__
class CV_EXPORTS_W Feature2D : public Algorithm
#else
class CV_EXPORTS_W Feature2D : public virtual Algorithm
#endif

Build warning is resolved:

Note: Class Feature2D has more than 1 base class (not supported by Python C extensions)
      Bases:  cv::Algorithm, cv::class, cv::Feature2D, cv::Algorithm
      Only the first base class will be used

Related diff in pyopencv_generated_types.h

# Before
CVPY_TYPE(Feature2D, Feature2D, Ptr<cv::Feature2D>, Ptr, NoBase, 0, "")
# After
CVPY_TYPE(Feature2D, Feature2D, Ptr<cv::Feature2D>, Ptr, Algorithm, 0, "")

Duplicate for cv::RotationWarper::warpPointBackward is removed from function dispatch.

#if CV_VERSION_MAJOR == 4
    virtual Point2f warpPointBackward(const Point2f& pt, InputArray K, InputArray R)
    {
        CV_UNUSED(pt); CV_UNUSED(K); CV_UNUSED(R);
        CV_Error(Error::StsNotImplemented, "");
    }
#else
    virtual Point2f warpPointBackward(const Point2f& pt, InputArray K, InputArray R) = 0;
#endif

Related diff in pyopencv_generated_types_content.h

Before

static PyObject* pyopencv_cv_PyRotationWarper_warpPointBackward(PyObject* self, PyObject* py_args, PyObject* kw)
{
    using namespace cv;


    Ptr<cv::PyRotationWarper> * self1 = 0;
    if (!pyopencv_PyRotationWarper_getp(self, self1))
        return failmsgp("Incorrect type of self (must be 'PyRotationWarper' or its derivative)");
    Ptr<cv::PyRotationWarper> _self_ = *(self1);
    pyPrepareArgumentConversionErrorsStorage(4);

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    Mat K;
    PyObject* pyobj_R = NULL;
    Mat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    Mat K;
    PyObject* pyobj_R = NULL;
    Mat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    UMat K;
    PyObject* pyobj_R = NULL;
    UMat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    UMat K;
    PyObject* pyobj_R = NULL;
    UMat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    pyRaiseCVOverloadException("warpPointBackward");

    return NULL;
}

After

static PyObject* pyopencv_cv_PyRotationWarper_warpPointBackward(PyObject* self, PyObject* py_args, PyObject* kw)
{
    using namespace cv;


    Ptr<cv::PyRotationWarper> * self1 = 0;
    if (!pyopencv_PyRotationWarper_getp(self, self1))
        return failmsgp("Incorrect type of self (must be 'PyRotationWarper' or its derivative)");
    Ptr<cv::PyRotationWarper> _self_ = *(self1);
    pyPrepareArgumentConversionErrorsStorage(2);

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    Mat K;
    PyObject* pyobj_R = NULL;
    Mat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    

    {
    PyObject* pyobj_pt = NULL;
    Point2f pt;
    PyObject* pyobj_K = NULL;
    UMat K;
    PyObject* pyobj_R = NULL;
    UMat R;
    Point2f retval;

    const char* keywords[] = { "pt", "K", "R", NULL };
    if( PyArg_ParseTupleAndKeywords(py_args, kw, "OOO:PyRotationWarper.warpPointBackward", (char**)keywords, &pyobj_pt, &pyobj_K, &pyobj_R) &&
        pyopencv_to_safe(pyobj_pt, pt, ArgInfo("pt", 0)) &&
        pyopencv_to_safe(pyobj_K, K, ArgInfo("K", 0)) &&
        pyopencv_to_safe(pyobj_R, R, ArgInfo("R", 0)) )
    {
        ERRWRAP2(retval = _self_->warpPointBackward(pt, K, R));
        return pyopencv_from(retval);
    }


        pyPopulateArgumentConversionErrors();
    }
    pyRaiseCVOverloadException("warpPointBackward");

    return NULL;
}

Closes #27250
Closes #27064
Closes #10175
Closes #12972

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

I agree to contribute to the project under Apache 2 License.
To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
The PR is proposed to the proper branch
There is a reference to the original bug report and related work
There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
The feature is well documented and sample code can be built with the project CMake

dkurt · 2025-05-16T11:16:18Z

Some related issues, can you please also check?
#10175
#12972

VadimLevin · 2025-05-16T11:43:33Z

Some related issues, can you please also check? #10175 #12972

Thank you. This patch resolves both mentioned issues. For #10175 if HAVE_OPENCV_FLANN resolves to 0

compile:
    [mkdir] Created dir: /Users/opencv-cn/GHA-OCV-3/_work/opencv/opencv/build/java_test/build/classes
    [javac] Compiling 63 source files to /Users/opencv-cn/GHA-OCV-3/_work/opencv/opencv/build/java_test/build/classes
    [javac] /Users/opencv-cn/GHA-OCV-3/_work/opencv/opencv/build/java_test/src/org/opencv/test/features2d/FlannBasedDescriptorMatcherTest.java:15: error: cannot find symbol
    [javac] import org.opencv.features2d.FlannBasedMatcher;
    [javac]                             ^
    [javac]   symbol:   class FlannBasedMatcher
    [javac]   location: package org.opencv.features2d

modules/python/src2/hdr_parser.py

cmake/OpenCVBindingsPreprocessorDefinitions.cmake

asmorkalov · 2025-05-19T07:52:03Z

@mshabunin @opencv-alalek could you take a look too?

dkurt · 2025-05-21T06:51:27Z

modules/python/src2/hdr_parser.py

+            "Failed to evaluate '{}' directive, stripped down to '{}'".format(
+                input_directive, directive
+            )
+        ) from e


Please check failed build https://pullrequest.opencv.org/buildbot/builders/precommit_windows64/builds/109668/steps/compile%20release/logs/stdio:

Traceback (most recent call last): File "C:/build/precommit_windows64/4.x/opencv/modules/java/generator/../generator/gen_java.py", line 1422, in <module> import hdr_parser File "C:\build\precommit_windows64\4.x\opencv\modules\python\src2\hdr_parser.py", line 154 ) from e ^ SyntaxError: invalid syntax opencv_gapi_SSE4_1.vcxproj -> C:\build\precommit_windows64\build\modules\gapi\opencv_gapi_SSE4_1.dir\Release\opencv_gapi_SSE4_1.lib Generate files for Python bindings and documentation C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.CppCommon.targets(171,5): error MSB6006: "cmd.exe" exited with code 1. [C:\build\precommit_windows64\build\modules\java_bindings_generator\gen_opencv_java_source.vcxproj] Traceback (most recent call last): File "C:/build/precommit_windows64/4.x/opencv/modules/python/src2/gen2.py", line 4, in <module> import hdr_parser, sys, re File "C:\build\precommit_windows64\4.x\opencv\modules\python\src2\hdr_parser.py", line 154 ) from e ^ SyntaxError: invalid syntax C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.CppCommon.targets(171,5): error MSB6006: "cmd.exe" exited with code 1. [C:

It requires Python update. I notified Alexander about it.

vrabaud · 2025-05-24T08:23:05Z

Thanks for the patch, that really helps. I have a different build system though (blaze) so I generate the binding files in CMake and then include them in blaze which works fine. Some users might need DNN in the bindings, others might not (typically, Java and Android Java) and one header for both is easier.

Would the following be possible: keep your patch but keep the guards in the bindings instead of removing the guarded sections. This way, the binding headers would be usable for different configurations (e.g. with or without HAVE_OPENCV_DNN being defined).

VadimLevin · 2025-07-24T08:10:18Z

Would the following be possible: keep your patch but keep the guards in the bindings instead of removing the guarded sections. This way, the binding headers would be usable for different configurations (e.g. with or without HAVE_OPENCV_DNN being defined).

Thank you for suggestion. Your approach requires significant changes in header parser and all bindings generators, because "availability information" should be a part of "function/enum/class/struct" definition. We can consider doing it once we begin reworking the header parser, updating intermediate representation and unifying all bindings generation.

VadimLevin requested a review from asmorkalov May 16, 2025 10:13

VadimLevin self-assigned this May 16, 2025

VadimLevin added bug category: python bindings labels May 16, 2025

VadimLevin force-pushed the dev/vlevin/header-parser-conditional-inclusion-directives-handling branch from 2392492 to 4a93fbd Compare May 16, 2025 10:25

VadimLevin force-pushed the dev/vlevin/header-parser-conditional-inclusion-directives-handling branch from 4a93fbd to d32123c Compare May 16, 2025 11:41

VadimLevin force-pushed the dev/vlevin/header-parser-conditional-inclusion-directives-handling branch 2 times, most recently from 4d8c249 to 4b68d2c Compare May 16, 2025 12:18

asmorkalov reviewed May 16, 2025

View reviewed changes

modules/python/src2/hdr_parser.py Outdated Show resolved Hide resolved

modules/python/src2/hdr_parser.py Outdated Show resolved Hide resolved

modules/python/src2/hdr_parser.py Outdated Show resolved Hide resolved

cmake/OpenCVBindingsPreprocessorDefinitions.cmake Show resolved Hide resolved

VadimLevin force-pushed the dev/vlevin/header-parser-conditional-inclusion-directives-handling branch from 4b68d2c to 6ac0816 Compare May 16, 2025 12:43

feat: add conditional inclusion support to header parser

b3e17ea

VadimLevin force-pushed the dev/vlevin/header-parser-conditional-inclusion-directives-handling branch from 6ac0816 to b3e17ea Compare May 19, 2025 07:43

asmorkalov approved these changes May 19, 2025

View reviewed changes

asmorkalov requested review from mshabunin and opencv-alalek May 19, 2025 07:51

asmorkalov added this to the 4.12.0 milestone May 20, 2025

asmorkalov merged commit 23f8e52 into opencv:4.x May 20, 2025
53 of 55 checks passed

asmorkalov mentioned this pull request May 20, 2025

OpenCV build without some internal modules fails in Linux and Windows opencv/opencv-python#1024

Closed

dkurt reviewed May 21, 2025

View reviewed changes

asmorkalov assigned asmorkalov and unassigned VadimLevin May 21, 2025

asmorkalov mentioned this pull request May 27, 2025

5.x merge 4.x #27370

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

feat: add conditional inclusion support to header parser#27325

feat: add conditional inclusion support to header parser#27325
asmorkalov merged 1 commit intoopencv:4.xfrom
VadimLevin:dev/vlevin/header-parser-conditional-inclusion-directives-handling

VadimLevin commented May 16, 2025 •

edited

Loading

Uh oh!

dkurt commented May 16, 2025 •

edited

Loading

Uh oh!

VadimLevin commented May 16, 2025

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

asmorkalov commented May 19, 2025

Uh oh!

Uh oh!

dkurt May 21, 2025 •

edited

Loading

Uh oh!

asmorkalov May 21, 2025

Uh oh!

vrabaud commented May 24, 2025

Uh oh!

VadimLevin commented Jul 24, 2025

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Uh oh!

Conversation

VadimLevin commented May 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Pull Request Readiness Checklist

Uh oh!

dkurt commented May 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

VadimLevin commented May 16, 2025

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

asmorkalov commented May 19, 2025

Uh oh!

Uh oh!

dkurt May 21, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

asmorkalov May 21, 2025

Choose a reason for hiding this comment

Uh oh!

vrabaud commented May 24, 2025

Uh oh!

VadimLevin commented Jul 24, 2025

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

VadimLevin commented May 16, 2025 •

edited

Loading

dkurt commented May 16, 2025 •

edited

Loading

dkurt May 21, 2025 •

edited

Loading