core: ARM64 loop unrolling in kmeans to improve Weighted Filter performance #27596
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modules/core/src/kmeans.cpp
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| { | ||
| double p = (double)rng*sum0; | ||
| int ci = 0; | ||
| #if defined(_M_ARM64) |
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#if CV_ENABLE_UNROLLED should be checked too.
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Hi @opencv-alalek , just following up on this PR. This loop unrolling has resulted in significant performance improvements in the WeightedMedianFilterTest function from the ximgproc module. |
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The patch shows speedup on other platforms too. |
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Mac M1 (single thread): |
asmorkalov
approved these changes
Sep 23, 2025
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This PR improves the performance of the Weighted Filter function from the ximgproc module on Windows on ARM64.
The optimization is achieved by unrolling two performance-critical loops in the generateCentersPP function in modules/core/src/kmeans.cpp, which is internally used by the Weighted Filter function.
The unrolling is enabled only for ARM64 builds using #if defined(_M_ARM64) guards to preserve compatibility and maintain performance on other architectures.
Performance Improvements: