Better Durand-Kerner Initialization #29109
While investigating issue #23644, I have found [this paper](https://link.springer.com/article/10.1007/BF01935059) which presents a good initialization for the Durand-Kerner algorithm. Basically the idea is to put the initial points equidistantly on a circle on the complex plane. The radius of the circle is computed as
<img width="607" height="178" alt="image" src="https://github.com/user-attachments/assets/ea31b002-c924-4b93-9334-3e59597c896b" />
Note that the $a_i$ coefficients in that paper are reversed compared to OpenCV. That's where the `(n - i)` in the code comes from.
I have implemented just the mean of the $u_i$'s for the sake of simplicity. That's already enough to make the algorithm converge in all cases I have tested. I have used this to test for convergence for many polynomials of order 2 and 4 and coefficients of different magnitudes:
```cpp
TEST(Core_SolvePoly, large_test)
{
cv::Mat_<float> coefs3(1,3);
cv::Mat_<float> coefs5(1,5);
cv::Mat r;
double prec;
for (int c0 = -20; c0 <= 20; c0++)
{
coefs3.at<float>(0) = c0;
for (int c1 = -20; c1 <= 20; c1++)
{
coefs3.at<float>(1) = c1;
for (int c2 = -20; c2 <= 20; c2++)
{
coefs3.at<float>(2) = c2;
prec = cv::solvePoly(coefs3, r);
EXPECT_LE(prec, 1e-6);
}
}
}
for (int c0 = -10; c0 <= 10; c0++)
{
coefs5.at<float>(0) = c0;
for (int c1 = -10; c1 <= 10; c1++)
{
coefs5.at<float>(1) = c1;
for (int c2 = -10; c2 <= 10; c2++)
{
coefs5.at<float>(2) = c2;
for (int c3 = -10; c3 <= 10; c3++)
{
coefs5.at<float>(3) = c3;
for (int c4 = -10; c4 <= 10; c4++)
{
coefs5.at<float>(4) = c4;
prec = cv::solvePoly(coefs5, r);
EXPECT_LE(prec, 1e-2);
}
}
}
}
}
for (int i = -10; i < 10; i++)
{
coefs3.at<float>(0) = pow(2, i);
for (int j = -10; j < 10; j++)
{
coefs3.at<float>(1) = pow(2, j);
for (int k = -10; k < 10; k++)
{
coefs3.at<float>(2) = pow(2, k);
prec = cv::solvePoly(coefs3, r);
EXPECT_LE(prec, 1e-6);
}
}
}
}
```
This test passes, but I have not committed it because it runs for a couple of seconds.
This fixes#23644 and replaces #29055. I have checked #29055 and it does not pass the test above. It seems to be optimized to the precise polynomial of #23644.
### Pull Request Readiness Checklist
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- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- [x] The PR is proposed to the proper branch
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Patch to opencv_extra has the same branch name.
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Add missing DataLayout constants in generated bindings for 5.x #29074
- Added DATA_LAYOUT_* constants to missing_consts so they
are manually injected into Core.java (same approach used for CV_8U, FILLED etc.)
- Added DataLayout entry to type_dict so the generator correctly maps
DataLayout
### Tests
modules/dnn/misc/java/test/DnnBlobFromImageWithParamsTest.java:
New test added:
- testDataLayoutConstants: verifies all DATA_LAYOUT_* constants are accessible from Core
Pre-existing tests enabled (were commented out earlier):
- testBlobFromImageWithParamsNHWCScalarScale: verifies blobFromImageWithParams
produces correct output with DATA_LAYOUT_NHWC and per-channel scalar scaling
- testBlobFromImageWithParams4chMultiImage: verifies blobFromImagesWithParams
correctly handles a batch of images with DATA_LAYOUT_NHWC layout
Closes : #27264
### Pull Request Readiness Checklist
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- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake
Introduce option to generate Java code with finalize() or Cleaners interface #28159
Closes https://github.com/opencv/opencv/issues/22260
Replaces https://github.com/opencv/opencv/pull/23467
The PR introduce configuration option to generate Java code with Cleaner interface for Java 9+ and old-fashion finalize() method for old Java and Android. Mat class and derivatives are manually written. The PR introduce 2 base classes for it depending on the generator configuration.
Pros:
1. No need to implement complex and error prone cleaner on library side.
2. No new CMake templates, easier to modify code in IDE.
Cons:
1. More generator branches and different code for modern desktop and Android.
TODO:
- [x] Add Java version check to cmake
- [x] Use Cleaners for ANDROID API 33+
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- Added vector_vector_Mat to gen_dict.json
- Implemented Mat_to_vector_vector_Mat and vector_vector_Mat_to_Mat conversion functions in converters.h/cpp and Converters.java
- Added DnnForwardAndRetrieve.java test to verify List<List<Mat>> conversion : Reference: C++ test in modules/dnn/test/test_misc.cpp - TEST(Net, forwardAndRetrieve)
Enable Java wrapper generation for Vec4i #27567
Fixes an issue where Java wrapper generation skips methods using Vec4i.
Related PR in opencv_contrib: https://github.com/opencv/opencv_contrib/pull/3988
The root cause was the absence of Vec4i in gen_java.json, which led to important methods such as aruco.drawCharucoDiamond() and ximgproc.HoughPoint2Line() being omitted from the Java bindings.
This PR includes the following changes:
- Added Vec4i definition to gen_java.json
- Updated gen_java.py to handle jintArray-based types properly
- ~~Also adjusted jn_args and jni_var for Vec2d and Vec3d to ensure correct JNI behavior~~
The modified Java wrapper generator successfully builds and includes the expected methods using Vec4i.
### Pull Request Readiness Checklist
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- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- [x] 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
* started working on adding 32u, 64u, 64s, bool and 16bf types to OpenCV
* core & imgproc tests seem to pass
* fixed a few compile errors and test failures on macOS x86
* hopefully fixed some compile problems and test failures
* fixed some more warnings and test failures
* trying to fix small deviations in perf_core & perf_imgproc by revering randf_64f to exact version used before
* trying to fix behavior of the new OpenCV with old plugins; there is (quite strong) assumption that video capture would give us frames with depth == CV_8U (0) or CV_16U (2). If depth is > 7 then it means that the plugin is built with the old OpenCV. It needs to be recompiled, of course and then this hack can be removed.
* try to repair the case when target arch does not have FP64 SIMD
* 1. fixed bug in itoa() found by alalek
2. restored ==, !=, > and < univ. intrinsics on ARM32/ARM64.
Build Java without ANT #23724
### Pull Request Readiness Checklist
Enables a path of building Java bindings without ANT
* Able to build OpenCV JAR and Docs without ANT
```
-- Java:
-- ant: NO
-- JNI: /usr/lib/jvm/default-java/include /usr/lib/jvm/default-java/include/linux /usr/lib/jvm/default-java/include
-- Java wrappers: YES
-- Java tests: NO
```
* Possible to build OpenCV JAR without ANT but tests still require ANT
**Merge with**: https://github.com/opencv/opencv_contrib/pull/3502
Notes:
- Use `OPENCV_JAVA_IGNORE_ANT=1` to force "Java" flow for building Java bindings
- Java tests still require Apache ANT
- JAR doesn't include `.java` source code files.
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake
* Expose more C++ functionality in the Java wrapper of the Mat class
In particular expose methods for handling Mat with more than 2 dimensions
* add constructors taking an array of dimension sizes
* add constructor taking an existing Mat and an array of Ranges
* add override of the create method taking an array of dimension sizes
* add overrides of the ones and zeros methods taking an array of dimension sizes
* add override of the submat method taking an array of ranges
* add overrides of put and get taking arrays of indices
* add wrapper for copySize method
* fix crash in the JNI wrapper of the reshape(int cn, int[] newshape) method
* add test for each method added to Mat.java
* Fix broken test
* make sure that the matrix with more than INT_MAX elements is marked as non-continuous, and thus all the pixel-wise functions process it correctly (i.e. row-by-row, not as a single row, where integer overflow may occur when computing the total number of elements)
Alexander Smorkalov
Adrian Kretz
Varun Jaiswal
Alexander Smorkalov
utibenkei
utibenkei
Onuralp SEZER
Alexander Smorkalov
Vadim Pisarevsky
Dmitry Kurtaev
Giles Payne
Alexander Alekhin
Alexander Alekhin
Maksim Shabunin
berak
Ahmed Ashour
Giles Payne
CUI Hao (Lab)
Dmitry Kurtaev
Sayed Adel