Frank Barchard 1ddb18fb6b [libyuv] AVX512, NEON, WASM and RVV alpha copy and mirror rows
1275x1650 (US Letter 150 DPI, 1000 iterations) speedup:

CPU            ARGBExtractAlpha ARGBCopyYToAlpha ARGBMirror RGB24Mirror
-----------------------------------------------------------------------
Intel Granite Rapids      1.00x            1.00x      1.00x       1.04x
Intel Emerald Rapids      1.01x            0.97x      1.03x       1.07x
Intel Sapphire Rapids     0.97x            1.01x      1.08x       1.26x
Intel Ice Lake            0.99x            1.02x      0.97x       1.08x
Intel Skylake-X           1.04x            1.03x      1.01x          NA
Intel Haswell                NA               NA         NA          NA
AMD Turin (Zen 5)         1.01x            1.10x      1.25x       1.31x
AMD Genoa (Zen 4)         0.97x            1.04x      1.09x       1.42x
AMD Milan (Zen 3)            NA               NA         NA          NA
AMD Rome (Zen 2)             NA               NA         NA          NA
NVIDIA Grace (V2)         1.57x            2.51x         NA          NA
Google Axion 2            1.12x            3.17x         NA          NA
Ampere Siryn              1.06x            1.70x         NA          NA
ARM Neoverse-N1           1.49x            2.01x         NA          NA
Google Axion (Maple)      1.47x            2.03x         NA          NA
ARM Cortex-A53            1.06x            1.69x         NA          NA

Add AVX512BW ARGBExtractAlphaRow, ARGBCopyYToAlphaRow and
ARGBMirrorRow, and AVX512VBMI RGB24MirrorRow, in row_gcc.cc and as
intrinsics in row_win.cc. They are x64 only. The remainder is done
with a k-mask (bzhi) zero-masked load and a masked store, so they
handle any width without an Any wrapper and never access memory
outside the row.

RGB24MirrorRow_AVX512VBMI loads and stores 3 full zmm vectors per
64 pixels using 3 vpermi2b. The one output byte that comes from the
third input vector is merged with a masked vpbroadcastb. The 1 to 63
pixel tail rebases the same tables by 192 - 3 * r; indices >= 128 are
taken from the third vector with vpmovb2m and a masked vpermb.

Add ARGBCopyYToAlphaRow_NEON for Arm 32 bit (vld4 + vst4) and
AArch64 (zip + sli), and rewrite AArch64 ARGBExtractAlphaRow_NEON
with ldp + uzp2. Both prefetch source and destination, which is
2.5x faster on Neoverse-N1 and 1.2x to 1.5x faster on Cortex-A53
for 1280x720. Add WASM SIMD ARGBExtractAlphaRow and
ARGBCopyYToAlphaRow, using a swizzle table for CopyYToAlpha. Rework
the RVV versions to use unit stride loads with vnsrl and vzext.vf4.


R=rrwinterton@gmail.com

Bug: None
Change-Id: I436f27d70a3db0a2b176c91eb789a9491133cfcb
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/8523531
Reviewed-by: richard winterton <rrwinterton@gmail.com>
Commit-Queue: Frank Barchard <fbarchard@google.com>
2026-10-07 12:44:53 -07:00
build_overrides [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
docs convert, scale: Add P010/P210/P410 convert paths and NV16/NV24/Px10 scale 2026-09-23 20:43:22 -07:00
include [libyuv] AVX512, NEON, WASM and RVV alpha copy and mirror rows 2026-10-07 12:44:53 -07:00
infra/config Use default xcode version in libyuv 2025-11-24 07:54:14 -08:00
riscv_script [libyuv] Fix RISC-V CMake/GN/Bazel builds and C compiler driver linking 2026-09-28 10:59:30 -07:00
source [libyuv] AVX512, NEON, WASM and RVV alpha copy and mirror rows 2026-10-07 12:44:53 -07:00
tools_libyuv Remove libyuv dependency on base/ 2025-01-08 09:04:21 -08:00
unit_test [libyuv] Add WASM SIMD128 and Relaxed SIMD for RAWToRGB24Row 2026-10-05 17:45:41 -07:00
util [libyuv] Add WASM SIMD128 and Relaxed SIMD for RAWToRGB24Row 2026-10-05 17:45:41 -07:00
.clang-format clang-format libyuv 2016-11-07 17:37:23 -08:00
.gitignore DetilePlane and unittest for NEON 2022-01-31 20:05:55 +00:00
.gn [build] Use hermetic python3 for script_executable in .gn 2026-09-28 06:02:39 -07:00
Android.bp [libyuv] Update build files with missing sources and sort lists 2026-09-03 11:02:07 -07:00
Android.mk [libyuv] Update build files with missing sources and sort lists 2026-09-03 11:02:07 -07:00
AUTHORS Fix same-width vertical point upsampling 2026-08-24 19:28:50 -07:00
BUILD.bazel [libyuv] Add WASM SIMD128 and Relaxed SIMD for RAWToRGB24Row 2026-10-05 17:45:41 -07:00
BUILD.gn [libyuv] Add WASM SIMD128 compare, rotate, scale and row functions 2026-10-06 19:05:05 -07:00
CM_linux_packages.cmake Use grep extended regex for version 2024-11-13 02:11:17 +00:00
CMakeLists.txt [libyuv] Add WASM SIMD128 compare, rotate, scale and row functions 2026-10-06 19:05:05 -07:00
codereview.settings [infra] remove no longer supported git cl upload setting. 2021-04-28 12:47:52 +00:00
DEPS [build] Use hermetic python3 for script_executable in .gn 2026-09-28 06:02:39 -07:00
DIR_METADATA Move metadata in OWNERS files to DIR_METADATA files 2021-02-09 19:34:43 +00:00
download_vs_toolchain.py Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
GEMINI.md GEMINI.md: Update Arm wording and guidance 2026-08-18 11:21:14 -07:00
libyuv.bzl [libyuv] Simplify RVV configuration in BUILD.bazel and libyuv.bzl 2026-09-08 17:50:17 -07:00
libyuv.gni [libyuv] Fix RISC-V CMake/GN/Bazel builds and C compiler driver linking 2026-09-28 10:59:30 -07:00
libyuv.gyp Stop setting --dynamic-linker for target_os="android" 2026-05-27 04:34:07 -07:00
libyuv.gypi [libyuv] Update build files with missing sources and sort lists 2026-09-03 11:02:07 -07:00
LICENSE Update Copyright notice to follow new chromium conventions. 2012-08-08 19:04:24 +00:00
linux.mk Deprecate MIPS and MSA support. 2025-10-16 12:20:40 -07:00
OWNERS Remove magjed from OWNERS 2026-08-24 10:43:21 -07:00
PATENTS LibYuv: Adding PATENT and LICENSE files 2011-10-25 16:15:49 +00:00
PRESUBMIT.py Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
public.mk use unix line endings 2018-06-20 23:19:59 +00:00
pylintrc Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
README.chromium ARGBToRGB24 AVX512 with tail masking 2026-09-29 16:15:44 -07:00
README.md Update README.md and environment_variables.md for Arm 2024-09-20 00:29:33 +00:00
vpython.toml [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
vpython.toml.uv.lock [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
winarm.mk NV12 Copy, include scale_uv.h 2020-12-08 18:54:16 +00:00
WORKSPACE.bazel Add Bazel build support 2026-04-15 18:20:26 -07:00

libyuv is an open source project that includes YUV scaling and conversion functionality.

  • Scale YUV to prepare content for compression, with point, bilinear or box filter.
  • Convert to YUV from webcam formats for compression.
  • Convert to RGB formats for rendering/effects.
  • Rotate by 90/180/270 degrees to adjust for mobile devices in portrait mode.
  • Optimized for SSSE3/AVX2 on x86/x64.
  • Optimized for Neon/SVE2/SME on Arm.
  • Optimized for MSA on Mips.
  • Optimized for RVV on RISC-V.

Development

See Getting started for instructions on how to get started developing.

You can also browse the docs directory for more documentation.