mirror of
https://chromium.googlesource.com/libyuv/libyuv
synced 2025-12-07 17:26:49 +08:00
5d694bec38
The existing Neon code makes use of a pair of UQSHRN and UQSHRN2
instructions to extract the top half of a widened multiply result.
These instructions would ordinarily saturate, however saturation can
never happen in this case since we are shifting by 16 to get the top
half of each element, the top bits remain as-is.
We could move this to using a slightly simpler non-saturating shift,
however in this case it is simpler and faster to just use UZP2 to
extract the top half of each 32-bit lane directly.
Reduction in runtime for selected kernels:
Kernel | Cortex-A55 | Cortex-A76 | Cortex-X2
I400ToARGBRow_NEON | -9.4% | -14.9% | -13.9%
I422AlphaToARGBRow_NEON | -7.9% | -11.4% | -11.5%
I422ToARGB1555Row_NEON | -7.3% | -17.2% | -14.7%
I422ToARGB4444Row_NEON | -7.6% | -17.9% | -13.7%
I422ToARGBRow_NEON | -8.2% | -9.8% | -11.9%
I422ToRGB24Row_NEON | -8.0% | -13.3% | -12.8%
I422ToRGB565Row_NEON | -7.5% | -15.1% | -14.6%
I422ToRGBARow_NEON | -8.3% | -13.1% | -12.2%
I444AlphaToARGBRow_NEON | -8.3% | -7.6% | -12.7%
I444ToARGBRow_NEON | -8.6% | -3.5% | -13.5%
I444ToRGB24Row_NEON | -8.5% | -7.8% | -13.4%
NV12ToARGBRow_NEON | -8.8% | -1.4% | -12.0%
NV12ToRGB24Row_NEON | -8.5% | -11.5% | -12.3%
NV12ToRGB565Row_NEON | -7.9% | -15.0% | -15.7%
NV21ToARGBRow_NEON | -8.7% | -1.6% | -12.3%
NV21ToRGB24Row_NEON | -8.4% | -11.5% | -12.0%
UYVYToARGBRow_NEON | -8.8% | -8.9% | -11.9%
YUY2ToARGBRow_NEON | -8.7% | -10.8% | -13.3%
Bug: libyuv:976
Change-Id: I6c505fe722e5f91f93718b85fe881ad056d8602d
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5366653
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
Commit-Queue: Frank Barchard <fbarchard@chromium.org>
|
||
|---|---|---|
| build_overrides | ||
| docs | ||
| include | ||
| infra/config | ||
| riscv_script | ||
| source | ||
| tools_libyuv | ||
| unit_test | ||
| util | ||
| .clang-format | ||
| .gitignore | ||
| .gn | ||
| .vpython | ||
| .vpython3 | ||
| Android.bp | ||
| Android.mk | ||
| AUTHORS | ||
| BUILD.gn | ||
| cleanup_links.py | ||
| CM_linux_packages.cmake | ||
| CMakeLists.txt | ||
| codereview.settings | ||
| DEPS | ||
| DIR_METADATA | ||
| download_vs_toolchain.py | ||
| libyuv.gni | ||
| libyuv.gyp | ||
| libyuv.gypi | ||
| LICENSE | ||
| linux.mk | ||
| OWNERS | ||
| PATENTS | ||
| PRESUBMIT.py | ||
| public.mk | ||
| pylintrc | ||
| README.chromium | ||
| README.md | ||
| winarm.mk | ||
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 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.