3.0 KiB
imagequant
Go bindings for libimagequant
libimagequant
is a library for lossy recompression of PNG images to reduce their filesize. It is used by the pngquant
tool. This go-imagequant
project is a set of bindings for libimagequant to enable its use from the Go programming language.
This binding was written by hand. The result is somewhat more idiomatic than an automated conversion, but some defer foo.Release()
calls are required for memory management.
Usage
Usage example is provided by a sample utility cmd/gopngquant
which mimics some functionality of the upstream pngquant
.
The sample utility has the following options:
Usage of gopngquant:
-In string
Input filename
-Out string
Output filename
-Speed int
Speed (1 slowest, 10 fastest) (default 3)
-Version
Building
This package can be installed via go get: go get code.ivysaur.me/imagequant
Import the package as code.ivysaur.me/imagequant/v2
and compile via go build
.
This is a CGO package and requires a C compiler installed. However, if you use go install
then future invocations of go build
do not require the C compiler to be present.
The imagequant.go
file also declares a number of CFLAGS
for GCC that allow the included libimagequant to build in a reasonably optimal way without using the upstream configure/make scripts.
License
I am releasing this binding under the ISC license, however, libimagequant
itself is released under GPLv3-or-later and/or commercial licenses. You must comply with the terms of such a license when using this binding in a Go project.
Changelog
2020-07-25 v2.12.6
- Update bundled libimagequant from 2.12.2 to 2.12.6
- Fix missing v2 in go.mod file causing failure to import in Modules mode
2018-12-31 v2.12.2-go1.2
- go-imagequant: Update bundled libimagequant from 2.9.0 to 2.12.2
- build: Switch to Go Modules
- build: Update bundled CFLAGS for new CGo whitelist (reduces performance)
- build: Remove nonportable Cygwin makefile
2017-03-03 v2.9.0-go1.1
- Previously tagged as 2.9go1.1
- go-imagequant: Update bundled libimagequant from 2.8.0 to 2.9.0
- go-imagequant: Separate
CGO_LDFLAGS
for Linux and Windows targets - gopngquant: Fix an issue with non-square images
- ⬇️ go-imagequant-2.9go1.1-src.zip (56.13 KiB)
- ⬇️ gopngquant-2.9go1.1-win64.7z (497.54 KiB)
2016-11-24 v2.8.0-go1.0
- Previously tagged as 2.8go1.0
- Initial public release
- ⬇️ go-imagequant-2.8go1.0-src.zip (55.40 KiB)
- ⬇️ gopngquant-2.8go1.0-win64.7z (497.98 KiB)
See also
- Pngquant homepage https://pngquant.org/
- Pngquant source code https://github.com/pornel/pngquant
- Libimagequant source code https://github.com/ImageOptim/libimagequant