opencv

Open Source Computer Vision Library https://opencv.org/

Liutong HAN 35571be570 Merge pull request #26318 from hanliutong:rvv-intrin-m2 Use LMUL=2 in the RISC-V Vector (RVV) backend of Universal Intrinsic. #26318 The modification of this patch involves the RVV backend of Universal Intrinsic, replacing `LMUL=1` with `LMUL=2`. Now each Universal Intrinsic type actually corresponds to two RVV vector registers, and each Intrinsic function also operates two vector registers. Considering that algorithms written using Universal Intrinsic usually do not use the maximum number of registers, this can help the RVV backend utilize more register resources without modifying the algorithm implementation This patch is generally beneficial in performance. We compiled OpenCV with `Clang-19.1.1` and `GCC-14.2.0` , ran it on `CanMV-k230` and `Banana-Pi F3`. Then we have four scenarios on combinations of compilers and devices. In `opencv_perf_core`, there are 3363 cases, of which: - 901 (26.8%) cases achieved more than `5%` performance improvement in all four scenarios, and the average speedup of these test cases (compared to scalar) increased from `3.35x` to `4.35x` - 75 (2.2%) cases had more than `5%` performance loss in all four scenarios, indicating that these cases are better with `LMUL=1` instead of `LMUL=2`. This involves `Mat_Transform`, `hasNonZero`, `KMeans`, `meanStdDev`, `merge` and `norm2`. Among them, `Mat_Transform` only has performance degradation in a few cases (`8UC3`), and the actual execution time of `hasNonZero` is so short that it can be ignored. For `KMeans`, `meanStdDev`, `merge` and `norm2`, we should be able to use the HAL to optimize/restore their performance. (In fact, we have already done this for `merge` #26216 ) ### 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		3 weeks ago
.github	Force contributors to define Apache 2.0 license for the new PRs.	5 months ago
3rdparty	Merge pull request #26216 from hanliutong:rvv-hal-merge	1 month ago
apps	Merge pull request #25582 from fengyuentau:dnn/dump_pbtxt	6 months ago
cmake	Merge pull request #26234 from zachlowry:apply-gcc6-fix-on-each-directory	1 month ago
data	Merge pull request #22727 from su77ungr:patch-1	2 years ago
doc	Merge pull request #26340 from Kumataro:wa26339	3 weeks ago
include	exclude opencv_contrib modules	5 years ago
modules	Merge pull request #26318 from hanliutong:rvv-intrin-m2	3 weeks ago
platforms	Merge pull request #25901 from mshabunin:fix-riscv-aarch-baseline	2 months ago
samples	Merge pull request #26212 from jamacias:feature/TickMeter-lasttime	1 month ago
.editorconfig	add .editorconfig	6 years ago
.gitattributes	cmake: generate and install ffmpeg-download.ps1	7 years ago
.gitignore	Merge pull request #17165 from komakai:objc-binding	5 years ago
CMakeLists.txt	build: set cmake policy for if(IN_LIST) support	4 weeks ago
CONTRIBUTING.md	migration: github.com/opencv/opencv	8 years ago
COPYRIGHT	copyright: 2023 (update)	2 years ago
LICENSE	Merge pull request #18073 from vpisarev:apache2_license	4 years ago
README.md	Space mistake in README.md	9 months ago
SECURITY.md	Updated PGP key for security reports	2 years ago

README.md

OpenCV: Open Source Computer Vision Library

Resources

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