Fix Python utility compatibility issues - #29755
### Problem
Several repository Python utilities emit invalid escape sequence
SyntaxWarnings under Python 3.13.
The Java test checker also attempts to parse non-Java assets as UTF-8,
causing UnicodeDecodeError, and relies on a global parser instance.
The Apple build utility accepts malformed CMake version strings because
one version separator is an unescaped regex wildcard.
### Changes
- Use raw strings for regular expressions and replacement templates.
- Skip non-Java files in the Java test checker.
- Use the current JavaParser instance instead of global state.
- Require literal dots in parsed CMake versions.
### Verification
- Compiled every tracked Python file with SyntaxWarning treated as an error.
- Ran the Java checker against modules/java/test successfully.
- Verified valid CMake versions are accepted and malformed versions rejected.
- Ran git diff --check.
Dynamic KV-cache support - #29642
The core idea is: reserveKVCache() API to pre-allocate memory for attention caches upfront, which eliminates allocation overhead during token decoding. For LLM inference, simply call reserveKVCache(prompt_len + max_new_tokens) before the prefill stage so the decode loop runs without page allocations, significantly reducing per-token latency for models like Gemma3 and Qwen.
Speedups after this PR on AMD Ryzen 9 9950X 16-Core Processor device:
Qwen2.5-0.5B-Instruct, fp32, CPU, tok/s:
```
Tokens Before After Speedup
64 12.49 23.72 1.90×
128 10.37 23.14 2.23×
256 7.20 22.40 3.11×
512 4.25 21.03 4.95×
```
Gemma 3 1B-it, fp32, CPU, 512 tokens :
```
Tokens Before After Speedup
64 6.99 11.84 1.69×
128 5.84 11.72 2.01×
256 4.17 11.50 2.76×
512 2.47 11.15 4.51×
```
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The Python tutorial sample thresholds the orientation with a single cv.threshold call, passing HighThr as the maxval argument rather than as an upper bound:
```_, imgOrientationBin = cv.threshold(imgOrientation, LowThr, HighThr, cv.THRESH_BINARY)```
That computes imgOrientation > LowThr ? HighThr : 0, so HighThr never restricts the angle. The C++ counterpart uses inRange(imgOrientation, Scalar(LowThr), Scalar(HighThr), imgOrientationBin), and the tutorial text states "LowThr and HighThr define orientation range", so the C++ behaviour is the intended one.
Add MatMulNBits layer and extend onnx coverage - #29666
Requires:https://github.com/opencv/opencv_extra/pull/1401
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Xfeat feature - #29361
## PR Description
### Summary
Integrate XFeat into OpenCV's `features` module as a native `Feature2D` implementation, enabling lightweight neural feature detection and descriptor extraction through OpenCV's standard feature extraction API.
---
### What's included
#### New class
- **`cv::XFeat`** extends `Feature2D`
- CNN-based keypoint detection
- 64-D descriptor extraction via ONNX/DNN
- Score-map based keypoint selection
- Descriptor sampling from the dense feature map
---
### Files added
| File | Description |
|------|-------------|
| `src/feature2d_xfeat.cpp` | XFeat `Feature2D` implementation |
| `test/test_xfeat.cpp` | XFeat unit and regression tests |
---
### Files modified
- `features.hpp`
- Add `cv::XFeat` declaration and public factory APIs
---
### Usage
```cpp
#include <opencv2/features.hpp>
using namespace cv;
// Feature extraction
Ptr<XFeat> xfeat =
XFeat::create("xfeat.onnx", 2000, 0.5f, 640);
std::vector<KeyPoint> keypoints;
Mat descriptors;
xfeat->detectAndCompute(image, noArray(), keypoints, descriptors);
```
---
### Test dependency
Depends on the opencv_extra changes adding the XFeat ONNX model and reference outputs.
Required test data:
https://github.com/opencv/opencv_extra/pull/1383
- `xfeat.onnx`
- `xfeat_lena_640_kpts.npy`
- `xfeat_lena_640_desc.npy`
These files are required for the `Features2d_XFeat` tests in the main OpenCV repository to validate XFeat feature extraction and descriptor generation.
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samples: fix HoughLines/HoughLinesP Python sample for 5.0 shape change (fixes#29637) - #29663
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Fixes#29637.
OpenCV 5.0 changed vector-backed Mat/OutputArray to true 1D arrays (see
migration guide: 1D and 0D array semantics). This changes HoughLines/
HoughLinesP Python return shape from (N,1,X) to (N,X), breaking the old
indexing pattern used in the tutorial sample.
Tested locally against opencv-python 5.0 — script runs without error,
lines drawn correctly on samples/data/sudoku.png.
Core, Highgui: OpenGL wrappers & window free-callback API #29485
This PR is a continuation of the work started in [20371](https://github.com/opencv/opencv/pull/20371)
### Pull Request Readiness Checklist
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fix: include ptcloud header and dependency for opengl_testdata_generator sample #29293
## Summary
Fixes the build failure in samples/opengl/opengl_testdata_generator.cpp on the 5.x
branch when building with BUILD_EXAMPLES=ON.
## Root cause
The sample uses `loadMesh`, `TriangleShadingType`, and `TriangleCullingMode`, all
declared in `modules/ptcloud/include/opencv2/ptcloud.hpp`. The sample did not
include this header, and `samples/opengl/CMakeLists.txt` did not list
`opencv_ptcloud` as a required dependency, so the ptcloud module headers/libs
were not available when compiling this sample.
## Changes
- Added `#include "opencv2/ptcloud.hpp"` to opengl_testdata_generator.cpp
- Added `opencv_ptcloud` to `OPENCV_OPENGL_SAMPLES_REQUIRED_DEPS` in
samples/opengl/CMakeLists.txt
## Acceptance criteria
- [x] opengl_testdata_generator.cpp compiles with BUILD_EXAMPLES=ON
- [x] ptcloud module dependency declared so build system links it correctly
Closes#29292
samples: add color-coded bounding boxes for multi QR code detection #29281
Improves the existing qrcode.py sample by adding color-coded bounding boxes when multiple QR codes are detected simultaneously.
Previously all QR codes were drawn with the same green color, making it hard to distinguish between them visually.
This change adds a QR_COLORS palette so each detected QR code gets a unique color, improving visual clarity for multi-QR detection.
Co-authored-by: Ayush Gupta <gupta.ayushg@gmail.com>
Enable collectContours in detect_blob.cpp and draw the per-blob
contours returned by getBlobContours(), so the sample exercises the
public contour-collection API added in #21942.
Refs #25904
[GSOC] feat: Add ALIKED feature extractor and LightGlue matcher with DNN integration #28986
## PR Description
### Summary
Integrate ALIKED and LightGlue into OpenCV's `features` module as native`Feature2D` and `DescriptorMatcher` implementations, enabling end-to-end neural feature matching within OpenCV's ecosystem.
---
### What's included
#### New classes
- **`cv::ALIKED`** extends `Feature2D`
- CNN-based keypoint detection
- 128-D descriptor extraction via ONNX Runtime
- **`cv::LightGlueMatcher`** extends `DescriptorMatcher`
- Deep feature matching with spatial context
- Uses keypoints and image sizes during matching
---
#### API design
- Standard OpenCV patterns:
- `detectAndCompute()`
- `match()`
- `knnMatch()`
- Multiple factory methods:
- ONNX model path
- In-memory model buffer
- Pre-loaded `dnn::Net`
- `Params` structs use `CV_EXPORTS_W_SIMPLE`
for Python/Java bindings support
- Optional DNN dependency:
- `HAVE_OPENCV_DNN` guards
- Stub implementations throw `StsNotImplemented`
---
### Files added
| File | Description |
|------|-------------|
| `src/feature2d_aliked.cpp` | ALIKED implementation |
| `src/matchers_lightglue.cpp` | LightGlueMatcher implementation |
| `src/aliked_context.hpp` | Shared internal context struct |
| `test/test_aliked_lightglue.cpp` | Unit tests (9 test cases) |
| `samples/cpp/example_features_aliked_lightglue.cpp` | Demo application |
---
### Files modified
- `CMakeLists.txt`
- Add `opencv_dnn` as optional dependency
- `features.hpp`
- Add ALIKED and LightGlueMatcher declarations
- `precomp.hpp`
- Add DNN include guard
---
### Usage
```cpp
// Feature extraction
Ptr<ALIKED> aliked =
ALIKED::create("aliked-n16rot-top1k-640.onnx");
vector<KeyPoint> kpts;
Mat descs;
aliked->detectAndCompute(image, Mat(), kpts, descs);
// Feature matching
Ptr<LightGlueMatcher> lg =
LightGlueMatcher::create("aliked_lightglue.onnx");
lg->setPairInfo(
kpts1Mat,
kpts2Mat,
img1.size(),
img2.size()
);
vector<DMatch> matches;
lg->match(descs1, descs2, matches);
````
please refer to samples/cpp/example_features_aliked_lightglue.cpp
---
### Test plan
* Build with `BUILD_LIST=features,dnn`
* Build without DNN:
* Verify stubs compile
* Verify `StsNotImplemented` is thrown
* Run:
* `ctest -R Features2d_ALIKED`
* `ctest -R Features2d_LightGlueMatcher`
* Run sample application with:
* Real images
* Real ONNX models
* Verify Python/Java bindings compile and work
---
### Related
Phase 1 of the
"End-to-End AI Feature Extraction and LightGlue Matching Pipeline"
GSoC project.
Designed to be extensible to:
* XFeat
* SuperPoint
* Other neural feature extractors
### test dependency
Depends on the opencv_extra PR adding ALIKED and LightGlue test models:
- [opencv_extra PR](https://github.com/opencv/opencv_extra/pull/1366)
This PR adds the following ONNX models to `download_models.py`:
- `aliked-n16rot-top1k-640.onnx`
- `aliked_lightglue.onnx`
These models are required for the `features2d` tests in the main OpenCV repository to validate the ALIKED and LightGlue feature extraction and matching pipeline.
### Pull Request Readiness Checklist
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[FOLLOW UP] : Documentation optimizations for the new Sphinx structure #29220
### Pull Request Readiness Checklist
This PR serves as a follow-up to the new documentation system introduced in [#29206](https://github.com/opencv/opencv/pull/29206)
Co-authored by: @abhishek-gola @kirtijindal14 @Akansha-977 @Prasadayus @varun-jaiswal17
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
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Inverted imgproc-geometry dependency and moved more functions to geometry #29230
Fixes: https://github.com/opencv/opencv/issues/20267
Continues: https://github.com/opencv/opencv/pull/29175
OpenCV Contrib: https://github.com/opencv/opencv_contrib/pull/4137
OpenCV Extra: https://github.com/opencv/opencv_extra/pull/1377
Summary:
- LSD returned back to imgproc
- drawing functions moved to imgproc
- undistort image and related perf-pixel functions moved to imgproc
- moments moved to geometry
- estimateXXXtransform moved to geometry
After the patch the geometry module depends on code and Flann and may be used everywhere without potential circular dependencies
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Update BarcodeDetector super-resolution API to use single-file ONNX #29227
### Pull Request Readiness Checklist
This PR updates the `BarcodeDetector` super-resolution API to support and utilize a single-file ONNX model format.
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
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Dedicated pointcloud module #29224
OpenCV contrib: https://github.com/opencv/opencv_contrib/pull/4134
### Pull Request Readiness Checklist
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Fixed Out-of-Memory issue and added VLM sample #29221
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Caffe importer cleanup #28678
Merge with: https://github.com/opencv/opencv_extra/pull/1324
### Pull Request Readiness Checklist
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Update default YuNet model to new dynamic inputs #29107
Update the default model in `face_detect.py` and `face_detect.cpp` to
`face_detection_yunet_2026may.onnx`, which has symbolic `height`/`width` input dims.
## Changes
- `samples/dnn/face_detect.py`: update default `--face_detection_model` to `face_detection_yunet_2026may.onnx`
- `samples/dnn/face_detect.cpp`: update default `fd_model` to `face_detection_yunet_2026may.onnx`
Companion PR :
- https://github.com/opencv/opencv_zoo/pull/310
- https://github.com/opencv/opencv_extra/pull/1373
Closes : https://github.com/opencv/opencv/issues/28769
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Moved geometry transformations from imgproc to 3d, future geometry module #29101
The first step of 2d geometry operations migration to the future geometry module.
I created 2d.hpp to isolate the moved functions for now. I propose to create geometry.hpp when the module is renamed and include all things there.
OpenCV contrib: https://github.com/opencv/opencv_contrib/pull/4126
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Migrated chessboard and circles grid detectors to objdetect #28804
OpenCV Contrib: https://github.com/opencv/opencv_contrib/pull/4125
OpenCV Extra: https://github.com/opencv/opencv_extra/pull/1375
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Add KV cache with paged attention and prefetch #29127
Closes: https://github.com/opencv/opencv/issues/27159
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