mirror of
https://github.com/python-pillow/Pillow.git
synced 2025-08-25 22:54:46 +03:00
fix list (+6 squashed commits)
Squashed commits: [c45b871] update for Pillow-SIMD 3.4.0 [bedd83f] no alpha compositing in this release [e8fe730] update results for latest version add Skia results [a16ff97] add SIMD changes [82ffbd6] fix readme (+4 squashed commits) Squashed commits: [85677f9] fix error [f44ebb1] update results for unrolled implementation [83968c3] fix #4 [cd73c51] update link (+11 squashed commits) Squashed commits: [5882178] correct spelling [a0e5956] Why Pillow-SIMD is even faster [108e72e] Why Pillow itself is so fast [e8eeda1] spelling fixes [e816e9c] spelling [d2eefef] methodology, why not contributed [2e55786] installation and conclusion [9f6415e] more info [67e55b7] more benchmarks test files [471d4c5] remove spaces [904d89d] add performance tests [4fe17fe] simple readme
This commit is contained in:
homm
Alexander
parent
0ac14725ef
commit
b5bad9489d
67
CHANGES.SIMD.rst
Normal file
67
CHANGES.SIMD.rst
Normal file
|
|
@ -0,0 +1,67 @@
|
||||||
|
Changelog (Pillow-SIMD)
|
||||||
|
=======================
|
||||||
|
|
||||||
|
3.3.0.post1
|
||||||
|
-----------
|
||||||
|
|
||||||
|
Alpha compositing
|
||||||
|
~~~~~~~~~~~~~~~~~
|
||||||
|
|
||||||
|
- SSE4 and AVX2 fixed-point full loading implementation.
|
||||||
|
Up to 4.6x faster.
|
||||||
|
|
||||||
|
3.3.0.post0
|
||||||
|
-----------
|
||||||
|
|
||||||
|
Resampling
|
||||||
|
~~~~~~~~~~
|
||||||
|
|
||||||
|
- SSE4 and AVX2 fixed-point full loading horizontal pass.
|
||||||
|
- SSE4 and AVX2 fixed-point full loading vertical pass.
|
||||||
|
|
||||||
|
Convertion
|
||||||
|
~~~~~~~~~~
|
||||||
|
|
||||||
|
- RGBA -> RGBa SSE4 and AVX2 fixed-point full loading implementations.
|
||||||
|
Up to 2.6x faster.
|
||||||
|
- RGBa -> RGBA AVX2 implementation using gather instructions.
|
||||||
|
Up to 5x faster.
|
||||||
|
|
||||||
|
|
||||||
|
3.2.0.post3
|
||||||
|
-----------
|
||||||
|
|
||||||
|
Resampling
|
||||||
|
~~~~~~~~~~
|
||||||
|
|
||||||
|
- SSE4 and AVX2 float full loading horizontal pass.
|
||||||
|
- SSE4 float full loading vertical pass.
|
||||||
|
|
||||||
|
|
||||||
|
3.2.0.post2
|
||||||
|
-----------
|
||||||
|
|
||||||
|
Resampling
|
||||||
|
~~~~~~~~~~
|
||||||
|
|
||||||
|
- SSE4 and AVX2 float full loading horizontal pass.
|
||||||
|
- SSE4 float per-pixel loading vertical pass.
|
||||||
|
|
||||||
|
|
||||||
|
2.9.0.post1
|
||||||
|
-----------
|
||||||
|
|
||||||
|
Resampling
|
||||||
|
~~~~~~~~~~
|
||||||
|
|
||||||
|
- SSE4 and AVX2 float per-pixel loading horizontal pass.
|
||||||
|
- SSE4 float per-pixel loading vertical pass.
|
||||||
|
- SSE4: Up to 2x for downscaling. Up to 3.5x for upscaling.
|
||||||
|
- AVX2: Up to 2.7x for downscaling. Up to 3.5x for upscaling.
|
||||||
|
|
||||||
|
|
||||||
|
Box blur
|
||||||
|
~~~~~~~~
|
||||||
|
|
||||||
|
- Simple SSE4 fixed-point implementations with per-pixel loading.
|
||||||
|
- Up to 2.1x faster.
|
||||||
183
README.md
Normal file
183
README.md
Normal file
|
|
@ -0,0 +1,183 @@
|
||||||
|
# Pillow-SIMD
|
||||||
|
|
||||||
|
Pillow-SIMD is "following" Pillow fork (which is PIL fork itself).
|
||||||
|
|
||||||
|
For more information about original Pillow, please
|
||||||
|
[read the documentation][original-docs],
|
||||||
|
[check the changelog][original-changelog] and
|
||||||
|
[find out how to contribute][original-contribute].
|
||||||
|
|
||||||
|
|
||||||
|
## Why SIMD
|
||||||
|
|
||||||
|
There are many ways to improve the performance of image processing.
|
||||||
|
You can use better algorithms for the same task, you can make better
|
||||||
|
implementation for current algorithms, or you can use more processing unit
|
||||||
|
resources. It is perfect when you can just use more efficient algorithm like
|
||||||
|
when gaussian blur based on convolutions [was replaced][gaussian-blur-changes]
|
||||||
|
by sequential box filters. But a number of such improvements are very limited.
|
||||||
|
It is also very tempting to use more processor unit resources
|
||||||
|
(via parallelization) when they are available. But it is handier just
|
||||||
|
to make things faster on the same resources. And that is where SIMD works better.
|
||||||
|
|
||||||
|
SIMD stands for "single instruction, multiple data". This is a way to perform
|
||||||
|
same operations against the huge amount of homogeneous data.
|
||||||
|
Modern CPU have different SIMD instructions sets like
|
||||||
|
MMX, SSE-SSE4, AVX, AVX2, AVX512, NEON.
|
||||||
|
|
||||||
|
Currently, Pillow-SIMD can be [compiled](#installation) with SSE4 (default)
|
||||||
|
and AVX2 support.
|
||||||
|
|
||||||
|
|
||||||
|
## Status
|
||||||
|
|
||||||
|
[![Uploadcare][uploadcare.logo]][uploadcare.com]
|
||||||
|
|
||||||
|
Pillow-SIMD can be used in production. Pillow-SIMD has been operating on
|
||||||
|
[Uploadcare][uploadcare.com] servers for more than 1 year.
|
||||||
|
Uploadcare is SAAS for image storing and processing in the cloud
|
||||||
|
and the main sponsor of Pillow-SIMD project.
|
||||||
|
|
||||||
|
Currently, following operations are accelerated:
|
||||||
|
|
||||||
|
- Resize (convolution-based resampling): SSE4, AVX2
|
||||||
|
- Gaussian and box blur: SSE4
|
||||||
|
- Alpha composition: SSE4, AVX2
|
||||||
|
- RGBA → RGBa (alpha premultiplication): SSE4, AVX2
|
||||||
|
- RGBa → RGBA (division by alpha): AVX2
|
||||||
|
|
||||||
|
See [CHANGES](CHANGES.SIMD.rst).
|
||||||
|
|
||||||
|
|
||||||
|
## Benchmarks
|
||||||
|
|
||||||
|
The numbers in the table represent processed megapixels of source RGB 2560x1600
|
||||||
|
image per second. For example, if resize of 2560x1600 image is done
|
||||||
|
in 0.5 seconds, the result will be 8.2 Mpx/s.
|
||||||
|
|
||||||
|
- Skia 53
|
||||||
|
- ImageMagick 6.9.3-8 Q8 x86_64
|
||||||
|
- Pillow 3.3.0
|
||||||
|
- Pillow-SIMD 3.3.0.post1
|
||||||
|
|
||||||
|
Operation | Filter | IM | Pillow| SIMD SSE4| SIMD AVX2| Skia 53
|
||||||
|
------------------------|---------|------|-------|----------|----------|--------
|
||||||
|
**Resize to 16x16** | Bilinear| 41.37| 337.12| 571.67| 903.40| 809.49
|
||||||
|
| Bicubic | 20.58| 185.79| 305.72| 552.85| 453.10
|
||||||
|
| Lanczos | 14.17| 113.27| 189.19| 355.40| 292.57
|
||||||
|
**Resize to 320x180** | Bilinear| 29.46| 209.06| 366.33| 558.57| 592.76
|
||||||
|
| Bicubic | 15.75| 124.43| 224.91| 353.53| 327.68
|
||||||
|
| Lanczos | 10.80| 82.25| 153.10| 244.22| 196.92
|
||||||
|
**Resize to 1920x1200** | Bilinear| 17.80| 55.87| 131.27| 152.11| 192.30
|
||||||
|
| Bicubic | 9.99| 43.64| 90.20| 112.34| 112.84
|
||||||
|
| Lanczos | 6.95| 34.51| 72.55| 103.16| 104.76
|
||||||
|
**Resize to 7712x4352** | Bilinear| 2.54| 6.71| 16.06| 20.33| 20.58
|
||||||
|
| Bicubic | 1.60| 5.51| 12.65| 16.46| 16.52
|
||||||
|
| Lanczos | 1.09| 4.62| 9.84| 13.38| 12.05
|
||||||
|
**Blur** | 1px | 6.60| 16.94| 35.16| |
|
||||||
|
| 10px | 2.28| 16.94| 35.47| |
|
||||||
|
| 100px | 0.34| 16.93| 35.53| |
|
||||||
|
|
||||||
|
|
||||||
|
### Some conclusion
|
||||||
|
|
||||||
|
Pillow is always faster than ImageMagick. And Pillow-SIMD is faster
|
||||||
|
than Pillow in 2—2.5 times. In general, Pillow-SIMD with AVX2 always
|
||||||
|
**8-20 times faster** than ImageMagick and almost equal to the Skia results,
|
||||||
|
high-speed graphics library used in Chromium.
|
||||||
|
|
||||||
|
### Methodology
|
||||||
|
|
||||||
|
All tests were performed on Ubuntu 14.04 64-bit running on
|
||||||
|
Intel Core i5 4258U with AVX2 CPU on the single thread.
|
||||||
|
|
||||||
|
ImageMagick performance was measured with command-line tool `convert` with
|
||||||
|
`-verbose` and `-bench` arguments. I use command line because
|
||||||
|
I need to test the latest version and this is the easiest way to do that.
|
||||||
|
|
||||||
|
All operations produce exactly the same results.
|
||||||
|
Resizing filters compliance:
|
||||||
|
|
||||||
|
- PIL.Image.BILINEAR == Triangle
|
||||||
|
- PIL.Image.BICUBIC == Catrom
|
||||||
|
- PIL.Image.LANCZOS == Lanczos
|
||||||
|
|
||||||
|
In ImageMagick, the radius of gaussian blur is called sigma and the second
|
||||||
|
parameter is called radius. In fact, there should not be additional parameters
|
||||||
|
for *gaussian blur*, because if the radius is too small, this is *not*
|
||||||
|
gaussian blur anymore. And if the radius is big this does not give any
|
||||||
|
advantages but makes operation slower. For the test, I set the radius
|
||||||
|
to sigma × 2.5.
|
||||||
|
|
||||||
|
Following script was used for testing:
|
||||||
|
https://gist.github.com/homm/f9b8d8a84a57a7e51f9c2a5828e40e63
|
||||||
|
|
||||||
|
|
||||||
|
## Why Pillow itself is so fast
|
||||||
|
|
||||||
|
There are no cheats. High-quality resize and blur methods are used for all
|
||||||
|
benchmarks. Results are almost pixel-perfect. The difference is only effective
|
||||||
|
algorithms. Resampling in Pillow was rewritten in version 2.7 with
|
||||||
|
minimal usage of floating point numbers, precomputed coefficients and
|
||||||
|
cache-awareness transposition.
|
||||||
|
|
||||||
|
|
||||||
|
## Why Pillow-SIMD is even faster
|
||||||
|
|
||||||
|
Because of SIMD, of course. There are some ideas how to achieve even better
|
||||||
|
performance.
|
||||||
|
|
||||||
|
- **Efficient work with memory** Currently, each pixel is read from
|
||||||
|
memory to the SSE register, while every SSE register can handle
|
||||||
|
four pixels at once.
|
||||||
|
- **Integer-based arithmetic** Experiments show that integer-based arithmetic
|
||||||
|
does not affect the quality and increases the performance of non-SIMD code
|
||||||
|
up to 50%.
|
||||||
|
- **Aligned pixels allocation** Well-known that the SIMD load and store
|
||||||
|
commands work better with aligned memory.
|
||||||
|
|
||||||
|
|
||||||
|
## Why do not contribute SIMD to the original Pillow
|
||||||
|
|
||||||
|
Well, it's not that simple. First of all, Pillow supports a large number
|
||||||
|
of architectures, not only x86. But even for x86 platforms, Pillow is often
|
||||||
|
distributed via precompiled binaries. To integrate SIMD in precompiled binaries
|
||||||
|
we need to do runtime checks of CPU capabilities.
|
||||||
|
To compile the code with runtime checks we need to pass `-mavx2` option
|
||||||
|
to the compiler. However this automatically activates all `if (__AVX2__)`
|
||||||
|
and below conditions. And SIMD instructions under such conditions exist
|
||||||
|
even in standard C library and they do not have any runtime checks.
|
||||||
|
Currently, I don't know how to allow SIMD instructions in the code
|
||||||
|
but *do not allow* such instructions without runtime checks.
|
||||||
|
|
||||||
|
|
||||||
|
## Installation
|
||||||
|
|
||||||
|
In general, you need to do `pip install pillow-simd` as always and if you
|
||||||
|
are using SSE4-capable CPU everything should run smoothly.
|
||||||
|
Do not forget to remove original Pillow package first.
|
||||||
|
|
||||||
|
If you want the AVX2-enabled version, you need to pass the additional flag to C
|
||||||
|
compiler. The easiest way to do that is define `CC` variable while compilation.
|
||||||
|
|
||||||
|
```bash
|
||||||
|
$ pip uninstall pillow
|
||||||
|
$ CC="cc -mavx2" pip install -U --force-reinstall pillow-simd
|
||||||
|
```
|
||||||
|
|
||||||
|
|
||||||
|
## Contributing to Pillow-SIMD
|
||||||
|
|
||||||
|
Pillow-SIMD and Pillow are two separate projects.
|
||||||
|
Please submit bugs and improvements not related to SIMD to
|
||||||
|
[original Pillow][original-issues]. All bugs and fixes in Pillow
|
||||||
|
will appear in next Pillow-SIMD version automatically.
|
||||||
|
|
||||||
|
|
||||||
|
[original-docs]: http://pillow.readthedocs.io/
|
||||||
|
[original-issues]: https://github.com/python-pillow/Pillow/issues/new
|
||||||
|
[original-changelog]: https://github.com/python-pillow/Pillow/blob/master/CHANGES.rst
|
||||||
|
[original-contribute]: https://github.com/python-pillow/Pillow/blob/master/.github/CONTRIBUTING.md
|
||||||
|
[gaussian-blur-changes]: http://pillow.readthedocs.io/en/3.2.x/releasenotes/2.7.0.html#gaussian-blur-and-unsharp-mask
|
||||||
|
[uploadcare.com]: https://uploadcare.com/?utm_source=github&utm_medium=description&utm_campaign=pillow-simd
|
||||||
|
[uploadcare.logo]: https://ucarecdn.com/dc4b8363-e89f-402f-8ea8-ce606664069c/-/preview/
|
||||||
2
setup.py
2
setup.py
|
|
@ -767,7 +767,7 @@ try:
|
||||||
setup(name=NAME,
|
setup(name=NAME,
|
||||||
version=PILLOW_VERSION,
|
version=PILLOW_VERSION,
|
||||||
description='Python Imaging Library (Fork)',
|
description='Python Imaging Library (Fork)',
|
||||||
long_description=_read('README.rst').decode('utf-8'),
|
long_description=_read('README.md').decode('utf-8'),
|
||||||
author='Alex Clark (Fork Author)',
|
author='Alex Clark (Fork Author)',
|
||||||
author_email='aclark@aclark.net',
|
author_email='aclark@aclark.net',
|
||||||
url='http://python-pillow.org',
|
url='http://python-pillow.org',
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue
Block a user