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1021 Commits

Author SHA1 Message Date
Alexander Smorkalov abb0115648 Merge branch 4.x 2026-07-09 12:17:24 +03:00
Jonas Perolini 37f3c7539b Merge pull request #29252 from JonasPerolini:pr-aruco-bit-threshold-in-refine
Use validBitIdThreshold for Aruco refineDetectedMarkers #29252

The goal of this PR is to solve the issue raised by @vrabaud in https://github.com/opencv/opencv/pull/28289 (comment: https://github.com/opencv/opencv/pull/28289#discussion_r3355812646). 

**Issue:** 

`refineDetectedMarkers()` converted the extracted cell ratios with `convertTo(CV_8UC1)` (an implicit 0.5 threshold) before computing the code distance, ignoring `detectorParams.validBitIdThreshold`. 

**Solution:** 

Make the refine path consistent with the main detection path `Dictionary::identify`.

**Changes:**

- Add a `Dictionary::getDistanceToId()` overload that takes the float cell pixel ratio matrix and `validBitIdThreshold` (similar to how it's done for the `identify()` overload.
- Move the per cell distance computation into a private `getDistanceToIdImpl` helper used by both `identify()` and the new overload of `getDistanceToId()` to avoid repetitions.
- `refineDetectedMarkers()` now calls the new overload.

**Tests:**

- `CV_ArucoRefine.validBitIdThreshold`: a marker with one degraded cell is recovered at threshold 0.7 but not at 0.49.
- `CV_ArucoDictionary.getDistanceToIdCellPixelRatio`: unit-tests both `getDistanceToId` overloads.

All passed
2026-06-29 13:37:43 +03:00
uwezkhan 15b5d28325 Merge pull request #29378 from uwezkhan:qr-alpha-map-bound
bound alphanumeric values in qr decodeAlpha before map lookup #29378

decodeAlpha in the no-quirc QR backend reads alphanumeric symbols from the post-ECC bitstream and indexes a fixed 45-entry map[] with the raw values. The 11-bit pair from next(11) goes up to 2047, so tuple/45 lands on 45 once the pair passes 2024, and the 6-bit trailing char from next(6) goes up to 63, so map[value] runs out to map[63]. A QR whose data codewords carry an alphanumeric segment with one of those out-of-range values reads past the static array, and the stray byte lands in the string returned by detectAndDecode. WITH_QUIRC defaults off, so this is the decoder a stock build runs.

Before, the only guard was on the encode side, which never emits those values, so the decoder trusted the stream and indexed map[] directly. New version checks value range and return empty string for malformed qr codes.

### Pull Request Readiness Checklist

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- [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
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2026-06-28 14:18:20 +03:00
Jonas Perolini 853ee9b961 Merge pull request #29329 from JonasPerolini:get-border-errors-once
Optimization ArUco: get border errors in one pass for both normal and inverted markers #29329

This PR is a follow up to optimization in https://github.com/opencv/opencv/pull/29267.

## Context:

When detecting inverted markers, we call `_getBorderErrors` twice:
- `int borderErrors = _getBorderErrors(cellPixelRatio, ...);`
- `Mat invCellPixelRatio = 1.f - cellPixelRatio;`
- `int invBError = _getBorderErrors(invCellPixelRatio, ...);`

meaning:

1. Scan border cells once.
2. Allocate a new Mat.
3. Invert the entire `cellPixelRatio` matrix, not just the border.
4. Scan border cells again on the inverted matrix.
5. If inverted marker is better, copy the full inverted matrix back

## Solution

only call `_getBorderErrors` once and compute both 
- borderErrors: `cellPixelRatio > validBitIdThreshold`
- invBorderErrors: `1 - cellPixelRatio > validBitIdThreshold`

This saves: 
1. full invert into temporary Mat: (`Mat invCellPixelRatio = 1.f - cellPixelRatio;`)
2. scan temporary border: the second `_getBorderErrors`
3. copy temporary Mat back into `cellPixelRatio`: `invCellPixelRatio.copyTo(cellPixelRatio);`

Note that the solution does not implement: 

```
 if(params.detectInvertedMarker) {
    _getBorderErrorsBoth(...);
} else {
    borderErrors = _getBorderErrors(...);
}
```

because the extra cost to computing invBorderErrors: `if(1.f - ratio > validBitIdThreshold) invBorderErrors++;` is negligible. this also avoids having to maintain two functions: `_getBorderErrorsBoth` and `_getBorderErrors`

## Tests:

No visible results when testing the full marker detection pipeline because this step is not expensive. There is a roughly 8% noise when re-running the marker detections making it hard to spot small speed diffs. 

When testing only this specific step with a float matrix of size: `(markerSize + 2*border)^2` on a AMD Ryzen 7 (8 cores / 16 threads):
 
-  The new code is 30-45× faster at this stage depending on the marker size and whether the candidate was actually an inverted one, saving ~530-580 ns per candidate, mainly because we removed `Mat invCellPixelRatio = 1.f - cellPixelRatio`
- The new code is equivalent when detecting non-inverted markers +/- 3 ns

---

### 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.
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2026-06-18 09:40:20 +03:00
Alexander Smorkalov 8bbe8eeb86 Merge pull request #29290 from vrabaud:mcc2
Get MCC to be deterministic
2026-06-15 17:08:29 +03:00
Alexander Smorkalov cfb3a8bbb7 Fixed new objdetect warnings on Windows. 2026-06-15 12:32:11 +03:00
Alexander Smorkalov 03539f67f5 Merge pull request #29289 from vrabaud:mcc1
Forward port MCC fix
2026-06-15 11:28:14 +03:00
Kumataro 9a966e96ad Merge pull request #29298 from Kumataro:remove_duplicated_bib
doc: remove duplicated bib #29298

### 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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2026-06-15 10:18:59 +03:00
Vincent Rabaud 7b7a62528f Get MCC to be deterministic 2026-06-12 17:13:15 +02:00
Vincent Rabaud 4c8c215d59 Forward port MCC fix
Somehow, https://github.com/opencv/opencv_contrib/pull/3939 was
not forward ported.
2026-06-12 17:09:22 +02:00
Vincent Rabaud fa55ed2837 Merge pull request #29267 from vrabaud:aruco
Fix speed regression in Aruco identify #29267

### Pull Request Readiness Checklist

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2026-06-11 20:54:39 +03:00
omrope79 ada32973b4 Merge pull request #29227 from omrope79:object_detect_changes
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

- [x] I agree to contribute to the project under Apache 2 License.
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- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
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      Patch to opencv_extra has the same branch name.
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2026-06-05 08:00:41 +03:00
s-trinh d9038ad00d Merge pull request #28823 from s-trinh:fix_apriltag_corners_order_update_doc
[OpenCV 5] Fix apriltag corners order and update the doc #28823

I have updated documentation for the AprilTag dictionaries.

Corresponding issues:
- https://github.com/opencv/opencv-python/issues/1195
- https://stackoverflow.com/questions/79044142/why-is-the-order-of-the-incoming-corners-different-between-apriltag-and-aruco-ma

This is a breaking change and is targeted only for OpenCV 5.

---

I have updated the ArUco doc with more information about fiducial markers detection.
I have tried to add some recommendations, best practices:
-  `DICT_ARUCO_MIP_36h12` should be the recommended family, [see](https://stackoverflow.com/a/51511558)
- link to download pregenerated markers for `MIP_36h12` is [here](https://sourceforge.net/projects/aruco/files/. I have not found some other official links for the other ArUco family, but since `MIP_36h12` should be used, I guess it is fined.
- recommendation to have a white border when printing the marker

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2026-06-04 23:28:46 +03:00
omrope79 b67ad9a422 Merge pull request #28678 from omrope79:caffe-importer-cleanup
Caffe importer cleanup #28678

Merge with: https://github.com/opencv/opencv_extra/pull/1324

### Pull Request Readiness Checklist

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2026-06-02 17:28:10 +03:00
Alexander Smorkalov 42fc6939f8 Merge pull request #29211 from vpisarev:fix_chessboard2_by_removing_ocl
Fixed the new chessboard detector by not using OpenCL #29211

This should hopefully fix test failures on macOS x64 builder in the latest 5.x branch.

The code of Chessboard detector (namely, the FastX part) runs tons of different-size box filters on the same image. Optimally, those filters need to be computed all together using once-computed integral image, but instead those multiple box filters, especially given how the current opencl path in box filter is organized, seem to 'overload' our OpenCL cache system and it breaks, at least on macOS. Given that boxfilter is relatively cheap operation, it will unlikely loose much by running on CPU vs GPU. So this is the current solution - switch to CPU path there. Local tests show that even on Apple M4 Max with very fast GPU we get better execution speed on CPU than on GPU.

### Pull Request Readiness Checklist

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- [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
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2026-06-02 16:20:12 +03:00
Vincent Rabaud 1d4d81103e Merge pull request #29077 from vrabaud:throw
Homogeneize some calib/3d behavior #29077

- use CV_Check to validate input sizes (thus throwing for invalid inputs)
- return bool to validate a function result

This fixes #22746

### Pull Request Readiness Checklist

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2026-06-02 08:25:44 +03:00
Vadim Pisarevsky e20acee958 use CPU path instead of OpenCL for image processing to avoid problems with myriads of different box filter OpenCL kernels 2026-06-02 00:47:36 +03:00
Alexander Smorkalov 59218f9edd Merge pull request #29175 from asmorkalov:as/geometry2
Geometry module #29175

OpenCV Contrib: https://github.com/opencv/opencv_contrib/pull/4129
CI changes: https://github.com/opencv/ci-gha-workflow/pull/313

Continues
- https://github.com/opencv/opencv/pull/28804
- https://github.com/opencv/opencv/pull/29101
- https://github.com/opencv/opencv/pull/29108
- https://github.com/opencv/opencv/pull/28810

Todo for followup PRs:
- [x] Rename doxygen groups
- [x] Fix JS modules layout and whitelists
- [ ] Sort tutorials code/snippets

### 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
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2026-05-31 14:23:15 +03:00
Alexander Smorkalov aac582119c Merge pull request #29101 from asmorkalov:as/geometry_module
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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2026-05-28 21:09:52 +03:00
Alexander Smorkalov e19b0ebc5c Merge pull request #28804 from asmorkalov:as/calib_boards_migration
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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2026-05-27 16:06:51 +03:00
Alexander Smorkalov d8263a9899 Merge branch 4.x 2026-05-25 17:49:25 +03:00
Alexander Smorkalov c9070f9f35 Merge branch 4.x 2026-05-20 17:57:51 +03:00
s-trinh 0abd5c86f7 Merge pull request #28824 from s-trinh:update_ArUco_doc
Update ArUco doc #28824

See https://github.com/opencv/opencv/pull/28823

Update of the ArUco doc but targeted for OpenCV 4.

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2026-05-20 15:05:51 +03:00
Rafael Muñoz Salinas 8c8b266b74 Merge pull request #29034 from rmsalinas:fix-arucodictionary
objdetect(aruco): fix maxCorrectionBits in predefined dictionaries #29034

This PR fixes the bugs in the creation of some dictionaries and standarizes its construction.

## Bugs
1. **DICT_ARUCO_MIP_36h12_DATA** was incorrectly assigned `maxCorrectionBits=12`, which is the intermarker distance. This was causing a high rate of false positives during detection, which is a significant problem.
2. **APRILTAG** dictionaries were incorrectly created with `maxCorrectionBits=0`, making it impossible to do error correction.

## Solution
Given a intermarker distance X, the correct `maxCorrectionBits = X/2 - 1`. Thus, standardize the construction of Dictionaries as such.
2026-05-19 09:18:29 +03:00
Kumataro 28b1f54468 core,objdetects,dnn,features2d: fix build warnings with GCC 16 2026-05-02 10:41:24 +09:00
Alexander Smorkalov 0ba385abe4 Merge pull request #28826 from ssam18:fix/yunet-dynamic-input-onnxruntime
objdetect: fix FaceDetectorYN dynamic input size for ONNX Runtime backend
2026-04-27 12:50:52 +03:00
Samaresh Kumar Singh 75c56661d7 objdetect: call setInputShape in FaceDetectorYN to support ONNX Runtime dynamic input 2026-04-24 07:57:49 -05:00
Alexander Smorkalov 7bde3f9ae9 Merge branch 4.x 2026-04-24 11:11:26 +03:00
Jeevan Mohan Pawar 273e52ce8d Merge pull request #28818 from jeevan6996:fix-charuco-detectdiamonds-clear-stale-output
objdetect: clear stale outputs in CharucoDetector::detectDiamonds #28818

## Summary
- clear `diamondCorners`/`diamondIds` outputs at the beginning of `CharucoDetector::detectDiamonds`
- prevent stale detections from previous calls when the current call has fewer than 4 markers or finds no diamonds
- add a regression test that pre-fills outputs, calls `detectDiamonds` with 3 markers, and verifies outputs are empty

Fixes #28783.

## Testing
- built `opencv_test_objdetect` locally
- ran `opencv_test_objdetect --gtest_filter=Charuco.detectDiamondsClearsOutputsWithLessThanFourMarkers`
- result: PASS
2026-04-22 15:42:37 +03:00
Vincent Rabaud ae6198e000 Rewrite getBitsFromByteList to avoid harmless buffer overflow
At the end, currentByte = byteList.ptr()[base + currentByteIdx];
could be out of bound though never used.
2026-04-15 16:14:25 +02:00
Alexander Smorkalov b5a7e0c662 Merge branch 4.x 2026-03-19 11:29:57 +03:00
Vadim Pisarevsky 1b483ffea6 Merge pull request #28585 from vpisarev:dnn_block_layout_v5
Block layout-based convolution in DNN #28585

merge together with https://github.com/opencv/opencv_extra/pull/1321

Some core parts of the new engine in DNN module have been revised substantially:

1. all tests seem to pass, except for `Test_Graph_Simplifier.ResizeSubgraph`, which has been disabled because it does not take the newly added `TransformLayoutLayer` into account. The test should be reworked perhaps.
1. convolution and related operations (maxpool/avgpool) now use so-called block layout (`DATA_LAYOUT_BLOCK`), where `NxCxHxW` tensors are represented  as `NxC1xHxWxC0`, where `C1=(C + C0-1)/C0` and `C0` is a power-of-two (usually 4, 8, 16 or 32).
1. graph is now pre-processed and `TransformLayoutLayer` is inserted to convert data from NCHW or NHWC layout to the block layout or vice versa. The transformations are done in a lazy way only when they are really needed. For example, in the whole Resnet only 2 transformations are performed.
1. transformer-based models and other models that do not use convolutions will run as usual, without going to block layout.
1. there is yet another graph preprocessing stage added that embeds constant weights/scale and bias into convolution and batch norm layers.
1. 'batchnorm', 'activation' and 'adding a residual' are now fused with convolution, just like in the old engine. That brings some noticeable acceleration.
1. optimized convolution kernels have been added.
     * depthwise convolution, as well as maxpool and avgpool support C0=4, 8, 16 etc. _as long as_  C0 is divisible by the number of fp32 lanes in a SIMD register of the target platform (e.g. on ARM with NEON there must be `C0 % 4 == 0`, on x64 with AVX2 `C0 % 8 == 0`).
     * non-depthwise convolution only supports C0=8 for now. C0=8 seems to be a sweetspot for ARM with NEON, x64 with AVX2 or RISC-V with RVV (with 128- or 256-bit registers). For some platforms with dedicated matrix accelerators C0=16 or even C0=32 might be more efficient, but we could add the respective kernels later.
     * only fp32 kernels have been added. fp16/bf16 kernels might be added a little later.

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2026-03-13 17:09:27 +03:00
Jonas Perolini 5e91b461bc Merge pull request #28289 from JonasPerolini:pr-aruco-identification
Identify ArUco markers based on threshold to reduce false positives #28289

**Goal:** parametrize the current marker identification process (pixel-based majority count) to reduce the number of false positives while maintaining high recall. Useful in high risk scenarios in which false positives are not acceptable. 

**Context:** This PR builds on top of https://github.com/opencv/opencv/pull/23190 in which we've introduced a pixel-based confidence in the marker detection.

**Solution:** Include a new parameter: `validBitIdThreshold` used to identify markers based on the pixel count of each cell. Set the parameter default either to 50% which is equivalent to the current majority count implementation or to 49% which already singnificantly reduces the number of false positives (see details below). 

**Test coverage:** 
- Unit tests: `CV_ArucoDetectionThreshold`, `CV_InvertedArucoDetectionThreshold`
- The impact of `validBitIdThreshold` on false positives was also tested using the benchmark dataset: `MIRFLICKR-25k` https://www.kaggle.com/datasets/skfrost19/mirflickr25k which contains random images without any markers. Every marker detection is a false positive. 

Example of images in the dataset:

![im2048](https://github.com/user-attachments/assets/3e38796b-67ce-44be-a91d-2fd268414515)

![im17627](https://github.com/user-attachments/assets/37253b9f-829d-4bac-b9fc-c844d16f546e)

**Results:** A threshold of 49% already allows to significantly reduce the number of false positives for the dict `DICT_4X4_1000`: 
- `5942` false positives for `validBitIdThreshold = 0.5`
- `629` false positives for `validBitIdThreshold = 0.49` and `0.46` 
   - number of false positives divided by `9.5` when compared to `validBitIdThreshold = 0.5`
- `139` false positives for `validBitIdThreshold = 0.43` and `0.4` 
   - number of false positives divided by `42` when compared to `validBitIdThreshold = 0.5`

Dicts with a higher number of cells are not as impacted since it's much harder to obtain false positives. However, the less cells in a marker the further away it can be reliably detected, so the dict `DICT_4X4_1000` is commonly used.

<img width="1280" height="800" alt="false_positive_image_rate" src="https://github.com/user-attachments/assets/1a0ee16a-221d-443e-835b-022ed6dea6b0" />

In the image attached, the values of `validBitIdThreshold` tested are:  `0.10f, 0.20f, 0.30f, 0.40f, 0.43f, 0.46f, 0.49f, 0.50f, 0.53f, 0.56f, 0.60f, 0.70f, 0.80f, 0.90f`

Summary of the results: [summary.csv](https://github.com/user-attachments/files/24315662/summary.csv)

Note that we can also analyse the number of false positives per marker `id`. For example, here's the histogram for the dict `DICT_4X4_1000`. (The CSV attached contains all the results)

<img width="1440" height="640" alt="false_positive_ids_DICT_4X4_1000_thr0 50" src="https://github.com/user-attachments/assets/af4f3ff8-9b8f-4682-9d51-a090c2610d8c" />

For example, the marker id 17 is detected 252 times with  `validBitIdThreshold = 0.5` and only 34 times with `validBitIdThreshold = 0.49`. Looking at marker 17 (see below), we understand that this simple pattern randomly occurs in images.

<img width="447" height="441" alt="Marker17" src="https://github.com/user-attachments/assets/f5d09227-b39b-4598-94f9-b529f8300703" />

Results for every dict and every `validBitIdThreshold` [per_id.csv](https://github.com/user-attachments/files/24315667/per_id.csv)

**Missing coverage:** there is no labeled dataset with images containing markers to analyse the impact of on the recall  (i.e. look at the true positive rate). For my specific use case (drones) any threshold above `0.4` allows to maintain a high recall in all conditions.

### Pull Request Readiness Checklist


- [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
2026-03-04 08:44:28 +03:00
Murat Raimbekov 91c78f5064 Merge pull request #28309 from raimbekovm:fix-typos-batch6
docs: fix typos in documentation and code comments #28309

## Summary

This PR fixes 10 spelling errors in documentation and code comments across 7 files.

## Changes
- `suppport` → `support` (2 occurrences in test_video_io.cpp)
- `compability` → `compatibility` (2 occurrences in face.hpp)
- `successfull` → `successful` (1 occurrence in cv2.cpp)
- `accomodate` → `accommodate` (2 occurrences in calib3d.hpp and test_camera.cpp)
- `minimun` → `minimum` (1 occurrence in aruco_detector.hpp)
- `maximun` → `maximum` (1 occurrence in aruco_detector.hpp)
- `orignal` → `original` (1 occurrence in aruco_detector.cpp)

## Test plan
- [x] No API changes
- [x] Documentation-only changes
- [x] Code compiles without errors
2026-03-03 14:29:47 +03:00
Alexander Smorkalov 6c995c768f Merge branch 4.x 2026-02-20 22:05:35 +03:00
Alexander Smorkalov 82ff8e45e9 Merge branch 4.x 2026-02-14 15:37:33 +03:00
Alexander Smorkalov 7b3977727c Merge pull request #28460 from falloficarus22:qrcode-remove-duplicated-compute
Optimize duplicated computation in QR code error correction
2026-02-10 09:17:15 +03:00
Siddharth Panditrao 0c613de006 Merge pull request #28380 from WalkingDevFlag:fix/charuco-detector-offset-25539
Fix ~0.5px systematic offset in CharucoDetector subpixel refinement #28380

Resolves #25539

### Problem

`CharucoDetector::detectBoard` produces Charuco corner coordinates that are consistently offset by approximately **+0.5 pixels** compared to `findChessboardCorners + cornerSubPix`.

This offset is systematic (mean ≈ −0.5 px when comparing legacy − Charuco) and reproducible across images. Visual inspection also shows that the legacy chessboard detector aligns better with the actual corner locations.

### Root cause

In `charuco_detector.cpp`, the points passed to `cornerSubPix` are manually shifted by `-Point2f(0.5f, 0.5f)` before refinement and then shifted back by `+Point2f(0.5f, 0.5f)` after refinement.

However, `cornerSubPix` refines corners in **absolute image coordinates** and converges to the true saddle point based on image gradients. Shifting the initial guess does not affect the converged result as long as the true corner lies within the refinement window.

The additional `+0.5` shift applied after refinement therefore introduces a constant bias, resulting in:

```

P_out = P_true + 0.5

```

### Solution

Remove the manual `±0.5` coordinate shifts around the `cornerSubPix` call and let the refined result be returned directly.

### Test updates

Updated expected corner values in the following tests:

- `testBoardSubpixelCoords`
- `testSeveralBoardsWithCustomIds`

The previous expected values (e.g. `200`, `250`, `300`) were only correct due to the +0.5px bias introduced by the bug.

`generateImage` creates checkerboard squares of exactly **50 pixels**, which places true corner locations on **pixel boundaries** rather than pixel centers. As a result, the correct subpixel coordinates are:

```

199.5, 249.5, 299.5

```

instead of the previously expected integer values.

After updating the expected values, all **30 Charuco-related tests pass** with the fix applied.

### Verification

I verified the fix using a Python reproducer that compares `CharucoDetector` output against `findChessboardCorners + cornerSubPix`:

- **Before fix:** mean error ≈ −0.501 px  
![before_fix_multilocus](https://github.com/user-attachments/assets/cc812956-c081-4f00-a7e2-78b7427b1235)
![before_fix_zoomed_small](https://github.com/user-attachments/assets/7e6887cb-b09d-47dc-9fcd-03a27b17f310)

- **After fix:** mean error ≈ −0.001 px
![after_fix_multilocus](https://github.com/user-attachments/assets/1c4f8dfa-d0ae-417c-881e-e2a9cbc4b9f1)
![after_fix_zoomed_small](https://github.com/user-attachments/assets/9c325995-fe0b-42f3-bdbb-6754f985e936)

After the change, the Charuco detector output aligns with the legacy chessboard detector both numerically and visually.

### Notes

This change only affects the post-refinement coordinate handling and does not alter detection logic, refinement parameters, or performance.

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
- [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
2026-01-28 14:31:54 +03:00
Murat Raimbekov 774c7e01b3 Merge pull request #28301 from raimbekovm:fix-more-typos
docs: fix spelling errors in documentation and code #28301

- [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
- [ ] The feature is well documented and sample code can be built with the project CMake

### Description

Fixed multiple spelling errors across documentation, comments, and code:

- 'colummn' → 'column' (cublas.hpp, 3 occurrences)
- 'points_per_colum' → 'points_per_column' (calib3d.hpp, 3 occurrences)
- 'Asignee' → 'Assignee' (sift files, 2 occurrences)
- 'compability' → 'compatibility' (face.hpp, 2 occurrences)
- 'orignal' → 'original' (aruco_detector.cpp)
- 'refrence' → 'reference' (chessboard.cpp)
- 'indeces' → 'indices' (stitching.hpp)
- 'OutputPrecison' → 'OutputPrecision' (test)
- 'tranform' → 'transform' (slice_layer.cpp, 3 occurrences)

Total: 24 fixes across 14 files. Documentation and comment changes only, no functional impact.
2026-01-26 21:28:50 +03:00
Abhishek b93ea5412c Optimize duplicated computation in QR code error correction
Precompute X values in Forney algorithm to eliminate redundant gfPow calls.

Previously, gfPow(2, ...) was computed multiple times for the same error
location across different loop iterations, resulting in O(L²) redundant
Galois field arithmetic operations.

This change:
- Precomputes all X values once before the main loop
- Reduces complexity from O(L²) to O(L) for X value computations
- Removes the TODO comment at line 1642
- No functional changes, only performance improvement

The optimization is most beneficial when there are many error locations
in QR codes (larger L values).
2026-01-24 17:21:12 +00:00
Alexander Smorkalov 74addff3d0 Merge pull request #28303 from raimbekovm:fix-typos-batch4
docs: fix spelling errors in code and comments
2026-01-23 13:42:15 +03:00
Alexander Smorkalov 5258bc5de9 Merge pull request #28317 from raimbekovm:fix-typos-batch7
docs: fix typos in documentation and code comments
2026-01-23 11:29:02 +03:00
Alexander Smorkalov 40ab411032 Merge pull request #28285 from akretz:fix_issue_28241
Fixed stack-use-after-scope errors in charuco detector
2025-12-27 18:17:58 +03:00
raimbekovm c058072d62 docs: fix typos in documentation and code comments
Fixed 19 typos across 15 files:
- properies → properties
- posible → possible (2×)
- indeces → indices
- matrixs → matrices (2×)
- grater → greater
- whith → with
- ouput → output
- choosen → chosen (4×)
- constains → contains
- refrence → reference
- dont → don't (4×)
- cant → can't
2025-12-26 23:42:51 +06:00
raimbekovm be7e2c91c6 docs: fix spelling errors in code and comments
- Fixed 'suported' -> 'supported' in imgproc.hpp
- Fixed 'constane/constans' -> 'constant/constants' in onevpl utils
- Fixed 'pushconstance' -> 'pushconstant' in op_matmul.cpp
- Fixed 'bufer' -> 'buffer' in test_imgwarp.cpp
- Fixed 'Framebuffrer' -> 'Framebuffer' in window_framebuffer
- Fixed 'readComplexPropery' -> 'readComplexProperty' in cap_msmf.cpp
- Fixed 'behavoir' -> 'behavior' in test_exr.impl.hpp
- Fixed 'previos' -> 'previous' in qrcode_encoder.cpp
2025-12-25 15:34:48 +06:00
Alexander Smorkalov 5c1737e0dc Merge pull request #28297 from raimbekovm:fix-documentation-typos
docs: fix typos in documentation
2025-12-25 08:35:19 +03:00
raimbekovm 17a01d687c docs: fix spelling errors in documentation
- Fixed 'reinitalized' -> 'reinitialized' in background_segm.hpp
- Fixed 'dimentions/dimentional/dimentinal' -> 'dimensions/dimensional' in mat.hpp, imgproc.hpp, gmat.hpp, recurrent_layers.cpp
- Fixed 'tresholded' -> 'thresholded' in aruco_detector.cpp
2025-12-24 22:37:09 +06:00
raimbekovm 2fb95415dd Fix typos in documentation: 'algorighm' -> 'algorithm', 'necesary' -> 'necessary' 2025-12-24 22:11:28 +06:00
Alexander Smorkalov a1b682254e Warning fix on Windows. 2025-12-23 18:25:26 +03:00
Adrian Kretz 54fc9dce0b Guarantee temporary object lifetime extension 2025-12-23 15:54:37 +01:00