README
¶
go-avif 
go-avif implements AVIF (AV1 Still Image File Format) encoder for Go using libaom, the high quality AV1 codec.
Requirements
Make sure libaom is installed. On typical Linux distro just run:
sudo apt-get install libaom-dev
Usage
To use go-avif in your Go code:
import "github.com/Kagami/go-avif"
To install go-avif in your $GOPATH:
go get github.com/Kagami/go-avif
For further details see GoDoc documentation.
Example
package main
import (
"image"
_ "image/jpeg"
"log"
"os"
"github.com/Kagami/go-avif"
)
func main() {
if len(os.Args) != 3 {
log.Fatalf("Usage: %s src.jpg dst.avif", os.Args[0])
}
srcPath := os.Args[1]
src, err := os.Open(srcPath)
if err != nil {
log.Fatalf("Can't open sorce file: %v", err)
}
dstPath := os.Args[2]
dst, err := os.Create(dstPath)
if err != nil {
log.Fatalf("Can't create destination file: %v", err)
}
img, _, err := image.Decode(src)
if err != nil {
log.Fatalf("Can't decode source file: %v", err)
}
err = avif.Encode(dst, img, nil)
if err != nil {
log.Fatalf("Can't encode source image: %v", err)
}
log.Printf("Encoded AVIF at %s", dstPath)
}
CLI
go-avif comes with handy CLI utility avif. It supports encoding of JPEG and
PNG files to AVIF:
# Compile and put avif binary to $GOPATH/bin
go get github.com/Kagami/go-avif/...
# Encode JPEG to AVIF with default settings
avif -e cat.jpg -o kitty.avif
# Encode PNG with slowest speed
avif -e dog.png -o doggy.avif --best -q 15
# Lossless encoding
avif -e pig.png -o piggy.avif --lossless
# Show help
avif -h
Static 64-bit builds for Windows, macOS and Linux are available at releases page. They include latest libaom from git at the moment of build.
Display
To display resulting AVIF files take a look at software listed here. E.g. use avif.js web viewer.
License
go-avif is licensed under CC0.
Documentation
¶
Overview ¶
Package avif implements a AVIF image encoder.
The AVIF specification is at https://aomediacodec.github.io/av1-avif/.
Example ¶
package main
import (
"image"
_ "image/jpeg"
"log"
"os"
"github.com/Kagami/go-avif"
)
const usageHelp = "Usage: %s src.jpg dst.avif"
func main() {
if len(os.Args) != 3 {
log.Fatalf(usageHelp, os.Args[0])
}
srcPath := os.Args[1]
src, err := os.Open(srcPath)
if err != nil {
log.Fatalf("Can't open sorce file: %v", err)
}
dstPath := os.Args[2]
dst, err := os.Create(dstPath)
if err != nil {
log.Fatalf("Can't create destination file: %v", err)
}
img, _, err := image.Decode(src)
if err != nil {
log.Fatalf("Can't decode source file: %v", err)
}
err = avif.Encode(dst, img, nil)
if err != nil {
log.Fatalf("Can't encode source image: %v", err)
}
log.Printf("Encoded AVIF at %s", dstPath)
}
Output:
Index ¶
Examples ¶
Constants ¶
const ( MinSpeed = 0 MaxSpeed = 8 MinQuality = 0 MaxQuality = 63 )
Encoder constants.
Variables ¶
var DefaultOptions = Options{ Threads: 0, Speed: 4, Quality: 25, SubsampleRatio: nil, }
DefaultOptions defines default encoder config.
Functions ¶
func Encode ¶
Encode writes the Image m to w in AVIF format with the given options. Default parameters are used if a nil *Options is passed.
NOTE: Image pixels are converted to RGBA first using standard Go library. This is no-op for PNG images and does the right thing for JPEG since they are normally stored as BT.601 full range with some chroma subsampling. Then pixels are converted to BT.709 limited range with specified chroma subsampling.
Alpha channel and monochrome are not supported at the moment. Only 4:2:0 8-bit images are supported at the moment.
Types ¶
type EncoderError ¶
type EncoderError int
An EncoderError reports that the encoder error has occured.
func (EncoderError) Error ¶
func (e EncoderError) Error() string
func (EncoderError) ToString ¶
func (e EncoderError) ToString() string
type MuxerError ¶
type MuxerError string
A MuxerError reports that the muxer error has occured.
func (MuxerError) Error ¶
func (e MuxerError) Error() string
type Options ¶
type Options struct {
Threads int
Speed int
Quality int
SubsampleRatio *image.YCbCrSubsampleRatio
}
Options are the encoding parameters. Threads ranges from 1, 0 means use all available cores. Speed ranges from MinSpeed to MaxSpeed. Quality ranges from MinQuality to MaxQuality, lower is better, 0 means lossless encoding. SubsampleRatio specifies subsampling of the encoded image, nil means 4:2:0.
type OptionsError ¶
type OptionsError string
An OptionsError reports that the passed options are not valid.
func (OptionsError) Error ¶
func (e OptionsError) Error() string
Source Files
Directories