x265-4.3

[Joe Locash]

MulticoreWare switched from bitbucket to github back in April and they stopped syncronizing repo's on June 30th so this slipped through the cracks. Currency will have to be updated for this change.

Version 4.3
===========

Release date - 31st July 2026

New feature
-----------
1. LoongArch64 architecture support
2. Foveated encoding - spatially varies quality around a gaze point, spending
   fewer bits in the viewer's periphery.
3. Selective (noise-based) MCSTF filtering avoiding unnecessary filtering
   cost/quality impact on low-noise content.

Enhancements to existing features
----------------------------------
1. MCSTF : Reworked Multi-threaded motion estimation and bilateral filtering,
   HME decoupled from the b-adapt flow, lowres planes generated with
   HM-equivalent averaging, TestBench harness support and profiling stats.
2. Visual Studio 2026 (vc18) build scripts.
3. Migrated continuous integration from Bitbucket Pipelines to GitHub Actions,
   with code-quality checks and smoke tests on pull requests.

API changes
-----------
1. Foveated encoding command-line options: :option:`--fovea-gaze`,
   :option:`--fovea-delta`, :option:`--fovea-sigma`, and
   :option:`--fovea-gaze-file`.
2. MCSTF command-line options: :option:`--selective-mcstf` and
   :option:`--mcstf-ref-range`.
3. Removed the MCSTF param-only options: temporalFilterStrength and
   searchRangeForLayers. Callers referencing the removed fields must be updated.

Optimizations
-------------
1. LoongArch64 SIMD optimizations across the loopfilter, ipfilter, DCT, motion
   compensation, block copy, pixel processing and intra-prediction modules.
2. AArch64 SIMD optimizations: improved Neon and SVE DCT16/DCT32, stride-aware
   DCT, new SVE2 implementations of psyCost, sa8d and satd, and faster Neon
   sa8d, satd and psyCost (including 12-bit sa8d).
3. AVX2 implementations for the MCSTF kernels resulted in speed up of 2x when
   combined with multithreading.
4. Threaded Motion Estimation: Early exit diamond search

Bug fixes
---------
1. Resolve ASAN/UBSAN reported out-of-bounds accesses and undefined behavior.
2. Fix TestBench segfault at high bit depth caused by alias trampolines.
3. Resolve TSAN data races in weight-analysis chroma extension, rate-control
   row stats, threaded-ME, and shared encoder state.
4. Fix MCSTF segfault and fix threaded-me crashes and multi-pool subscription
   issue
5. Fix scenecut not being active when :option:`--bframes` is 0.
6. Fix incorrect thread-pool size and regression in :option:`--pools` behaviour
7. Fix bitstream error when VUI timing info is disabled.
8. Fix i686 build failure (non-PC-relative PLT references) and PowerPC64 build
   with Clang.
9. Fix AArch64 filter-prim-sve test failures.
10. CPU feature detection fixes for OpenBSD/FreeBSD (elf_aux_info) and PowerPC.
11. Silence Clang -Wnontrivial-memcall and -Wundef warnings; assorted
    build-warning cleanups.

Known issues
------------
1. Performance regression observed with the threaded-me feature on
   high-frequency systems and higher resolutions (4k).
2. Inconsistent hash mismatch with abr-ladder feature

[Bruce Dubbs]

Fixed at commits:

2240b07a36 Update to glycin-2.2.1.
603afed78d Update to xfsprogs-7.2.0.
b567a02984 Update to WebKitGTK-2.54.0.
7b84efa233 Update to x265_4.3.