mirror of
https://github.com/lovell/sharp.git
synced 2025-07-09 18:40:16 +02:00
d26f6b3b89
Add structure via mkdocs (replaces ever-growing README) Inline usage examples with the method they demonstrate Add changelog
104 lines
3.8 KiB
Markdown
104 lines
3.8 KiB
Markdown
# sharp
|
|
|
|
The typical use case for this high speed Node.js module
|
|
is to convert large images of many formats to
|
|
smaller, web-friendly JPEG, PNG and WebP images of varying dimensions.
|
|
|
|
Resizing an image is typically 4x faster than using
|
|
the quickest ImageMagick and GraphicsMagick settings.
|
|
|
|
[](https://coveralls.io/r/lovell/sharp?branch=master)
|
|
|
|
### Formats
|
|
|
|
This module supports reading JPEG, PNG, WebP, TIFF, OpenSlide,
|
|
GIF and other libmagick-supported formats.
|
|
|
|
Output images can be in JPEG, PNG and WebP formats as well as uncompressed raw pixel data.
|
|
|
|
Streams, Buffer objects and the filesystem can be used for input and output.
|
|
|
|
A single input Stream can be split into multiple processing pipelines and output Streams.
|
|
|
|
Deep Zoom image pyramids can be generated,
|
|
suitable for use with "slippy map" tile viewers like
|
|
[OpenSeadragon](https://github.com/openseadragon/openseadragon)
|
|
and [Leaflet](https://github.com/turban/Leaflet.Zoomify).
|
|
|
|
### Features
|
|
|
|
As well as image resizing, operations such as
|
|
rotation, extraction, compositing and gamma correction are available.
|
|
|
|
Colour spaces, embedded ICC profiles and alpha transparency channels
|
|
are all handled correctly.
|
|
|
|
### Fast
|
|
|
|
This module is powered by the blazingly fast
|
|
[libvips](https://github.com/jcupitt/libvips) image processing library,
|
|
originally created in 1989 at Birkbeck College
|
|
and currently maintained by
|
|
[John Cupitt](https://github.com/jcupitt).
|
|
|
|
Only small regions of uncompressed image data
|
|
are held in memory and processed at a time,
|
|
taking full advantage of multiple CPU cores and L1/L2/L3 cache.
|
|
|
|
Everything remains non-blocking thanks to _libuv_,
|
|
no child processes are spawned and Promises/A+ are supported.
|
|
|
|
### Optimal
|
|
|
|
Huffman tables are optimised when generating JPEG output images
|
|
without having to use separate command line tools like
|
|
[jpegoptim](https://github.com/tjko/jpegoptim) and
|
|
[jpegtran](http://jpegclub.org/jpegtran/).
|
|
|
|
PNG filtering can be disabled,
|
|
which for diagrams and line art often produces the same result
|
|
as [pngcrush](http://pmt.sourceforge.net/pngcrush/).
|
|
|
|
### Contributing
|
|
|
|
A [guide for contributors](https://github.com/lovell/sharp/blob/master/CONTRIBUTING.md)
|
|
covers reporting bugs, requesting features and submitting code changes.
|
|
|
|
### Credits
|
|
|
|
This module would never have been possible without
|
|
the help and code contributions of the following people:
|
|
|
|
* [John Cupitt](https://github.com/jcupitt)
|
|
* [Pierre Inglebert](https://github.com/pierreinglebert)
|
|
* [Jonathan Ong](https://github.com/jonathanong)
|
|
* [Chanon Sajjamanochai](https://github.com/chanon)
|
|
* [Juliano Julio](https://github.com/julianojulio)
|
|
* [Daniel Gasienica](https://github.com/gasi)
|
|
* [Julian Walker](https://github.com/julianwa)
|
|
* [Amit Pitaru](https://github.com/apitaru)
|
|
* [Brandon Aaron](https://github.com/brandonaaron)
|
|
* [Andreas Lind](https://github.com/papandreou)
|
|
* [Maurus Cuelenaere](https://github.com/mcuelenaere)
|
|
* [Linus Unnebäck](https://github.com/LinusU)
|
|
* [Victor Mateevitsi](https://github.com/mvictoras)
|
|
* [Alaric Holloway](https://github.com/skedastik)
|
|
* [Bernhard K. Weisshuhn](https://github.com/bkw)
|
|
|
|
Thank you!
|
|
|
|
### Licence
|
|
|
|
Copyright 2013, 2014, 2015 Lovell Fuller and contributors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
[http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0.html)
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|