Reduce the buffer usage in `QualitySSIM::compute`

[lumina37]

Reduce the buffer usage in QualitySSIM::compute by safely reusing I1_I2, mu1_mu2 and sigma12.

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
• [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 Patch to opencv_extra has the same branch name.
• [ ] The feature is well documented and sample code can be built with the project CMake

[lumina37]

The test result on my own PC:

CTEST_FULL_OUTPUT
OpenCV version: 4.10.0-dev
OpenCV VCS version: b2e118e
Build type: Debug
Compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.41.34120/bin/Hostx64/x64/cl.exe  (ver 19.41.34120.0)
Algorithm hint: ALGO_HINT_ACCURATE
HAL: NO
[ INFO:[email protected]] global registry_parallel.impl.hpp:96 cv::parallel::ParallelBackendRegistry::ParallelBackendRegistry core(parallel): Enabled backends(3, sorted by priority): ONETBB(1000); TBB(990); OPENMP(980)
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load E:\Code\Cpp\opencv\cmake-build-debug\bin\opencv_core_parallel_onetbb4100_64d.dll => FAILED
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load opencv_core_parallel_onetbb4100_64d.dll => FAILED
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load E:\Code\Cpp\opencv\cmake-build-debug\bin\opencv_core_parallel_tbb4100_64d.dll => FAILED
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load opencv_core_parallel_tbb4100_64d.dll => FAILED
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load E:\Code\Cpp\opencv\cmake-build-debug\bin\opencv_core_parallel_openmp4100_64d.dll => FAILED
[ INFO:[email protected]] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load opencv_core_parallel_openmp4100_64d.dll => FAILED
Parallel framework: ms-concurrency (nthreads=24)
CPU features: SSE SSE2 SSE3 SSSE3 SSE4.1 POPCNT SSE4.2 AVX FP16 AVX2 FMA3
TEST: Skip tests with tags: 'mem_6gb', 'verylong', 'debug_verylong'
[==========] Running 17 tests from 5 test cases.
[----------] Global test environment set-up.
[----------] 5 tests from CV_Quality_BRISQUE
[ RUN      ] CV_Quality_BRISQUE.static_
[     SKIP ] OpenCV tests: Can't find data file: brisque_range_live.yml
[       OK ] CV_Quality_BRISQUE.static_ (1 ms)
[ RUN      ] CV_Quality_BRISQUE.single_channel
[     SKIP ] OpenCV tests: Can't find data file: brisque_model_live.yml
[       OK ] CV_Quality_BRISQUE.single_channel (1 ms)
[ RUN      ] CV_Quality_BRISQUE.multi_channel
[     SKIP ] OpenCV tests: Can't find data file: brisque_model_live.yml
[       OK ] CV_Quality_BRISQUE.multi_channel (9 ms)
[ RUN      ] CV_Quality_BRISQUE.model_persistence
[     SKIP ] OpenCV tests: Can't find data file: brisque_model_live.yml
[       OK ] CV_Quality_BRISQUE.model_persistence (0 ms)
[ RUN      ] CV_Quality_BRISQUE.compute_features
[     SKIP ] OpenCV tests: Can't find data file: brisque_model_live.yml
[       OK ] CV_Quality_BRISQUE.compute_features (0 ms)
[----------] 5 tests from CV_Quality_BRISQUE (11 ms total)

[----------] 3 tests from CV_Quality_GMSD
[ RUN      ] CV_Quality_GMSD.static_
[       OK ] CV_Quality_GMSD.static_ (7 ms)
[ RUN      ] CV_Quality_GMSD.single_channel
[       OK ] CV_Quality_GMSD.single_channel (12 ms)
[ RUN      ] CV_Quality_GMSD.multi_channel
[       OK ] CV_Quality_GMSD.multi_channel (57 ms)
[----------] 3 tests from CV_Quality_GMSD (76 ms total)

[----------] 3 tests from CV_Quality_MSE
[ RUN      ] CV_Quality_MSE.static_
[       OK ] CV_Quality_MSE.static_ (3 ms)
[ RUN      ] CV_Quality_MSE.single_channel
[       OK ] CV_Quality_MSE.single_channel (6 ms)
[ RUN      ] CV_Quality_MSE.multi_channel
[       OK ] CV_Quality_MSE.multi_channel (34 ms)
[----------] 3 tests from CV_Quality_MSE (43 ms total)

[----------] 3 tests from CV_Quality_PSNR
[ RUN      ] CV_Quality_PSNR.static_
[       OK ] CV_Quality_PSNR.static_ (3 ms)
[ RUN      ] CV_Quality_PSNR.single_channel
[       OK ] CV_Quality_PSNR.single_channel (5 ms)
[ RUN      ] CV_Quality_PSNR.multi_channel
[       OK ] CV_Quality_PSNR.multi_channel (34 ms)
[----------] 3 tests from CV_Quality_PSNR (42 ms total)

[----------] 3 tests from CV_Quality_SSIM
[ RUN      ] CV_Quality_SSIM.static_
[       OK ] CV_Quality_SSIM.static_ (18 ms)
[ RUN      ] CV_Quality_SSIM.single_channel
[       OK ] CV_Quality_SSIM.single_channel (34 ms)
[ RUN      ] CV_Quality_SSIM.multi_channel
[       OK ] CV_Quality_SSIM.multi_channel (158 ms)
[----------] 3 tests from CV_Quality_SSIM (210 ms total)

[----------] Global test environment tear-down
[ SKIPSTAT ] 5 tests skipped
[ SKIPSTAT ] TAG='skip_other' skip 5 tests
[==========] 17 tests from 5 test cases ran. (382 ms total)
[  PASSED  ] 17 tests.

Thanks for your review!

[lumina37]

@asmorkalov dear maintainer, could you please take a moment to review this simple commit?