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

feat(imgproc): add hal for calcHist and implemented in hal/riscv-rvv

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fengyuentau added this to the4.12.0 milestone

May 19, 2025

fengyuentau requested a review fromasmorkalov

May 19, 2025 07:47

fengyuentau added the optimization label

May 19, 2025

fengyuentau added this toOpenCV 4.x HAL improvement

May 19, 2025

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May 19, 2025

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fengyuentau commentedMay 19, 2025

Performance numbers:

K1 base vs. patch

GCC

               Name of Test                 base-gcc patch-gcc patch-gcc                                                                    vs                                                                    base-gcc                                                                (x-factor)calcHist1d::Size_Source::(2048x1536, 8UC1)   10.301   10.283      1.00   calcHist1d::Size_Source::(2048x1536, 16UC1)  85.365   27.098      3.15   calcHist1d::Size_Source::(2048x1536, 32FC1)  89.674   26.296      3.41   calcHist1d::Size_Source::(2592x1944, 8UC1)   16.469   16.458      1.00   calcHist1d::Size_Source::(2592x1944, 16UC1) 136.727   43.451      3.15   calcHist1d::Size_Source::(2592x1944, 32FC1) 143.641   42.020      3.42

Clang

               Name of Test                 base-clang patch-clang patch-clang                                                                       vs                                                                        base-clang                                                                    (x-factor) calcHist1d::Size_Source::(2048x1536, 8UC1)    14.683     14.731       1.00    calcHist1d::Size_Source::(2048x1536, 16UC1)   93.299     24.766       3.77    calcHist1d::Size_Source::(2048x1536, 32FC1)   97.666     24.055       4.06    calcHist1d::Size_Source::(2592x1944, 8UC1)    23.483     23.554       1.00    calcHist1d::Size_Source::(2592x1944, 16UC1)  149.431     39.502       3.78    calcHist1d::Size_Source::(2592x1944, 32FC1)  156.469     38.562       4.06

K1 vs. RK3568

               Name of Test                   rk   patch-gcc patch-clang patch-gcc  patch-clang                                                                             vs         vs                                                                                  rk         rk                                                                              (x-factor) (x-factor) calcHist1d::Size_Source::(2048x1536, 8UC1)  7.793   10.322     14.695       0.75       0.53    calcHist1d::Size_Source::(2048x1536, 16UC1) 53.658  27.125     24.734       1.98       2.17    calcHist1d::Size_Source::(2048x1536, 32FC1) 53.998  26.311     24.013       2.05       2.25    calcHist1d::Size_Source::(2592x1944, 8UC1)  12.512  16.451     23.506       0.76       0.53    calcHist1d::Size_Source::(2592x1944, 16UC1) 86.154  43.486     39.513       1.98       2.18    calcHist1d::Size_Source::(2592x1944, 32FC1) 86.718  42.062     38.569       2.06       2.25