7.5 KiB
bimg 
Small Go library for blazing fast and efficient image processing based on libvips using C bindings.
bimg is designed to be a small and efficient library with a generic and useful set of features.
It uses internally libvips, which requires a low memory footprint
and it's typically 4x faster than using the quickest ImageMagick and GraphicsMagick settings or Go native image package, and in some cases it's even 8x faster processing JPEG images.
It can read JPEG, PNG, WEBP, TIFF and Magick formats and it can output to JPEG, PNG and WEBP. It supports common image transformation operations such as crop, resize, rotate... and conversion between multiple formats.
For getting started, take a look to the examples and programmatic API documentation.
bimg was heavily inspired in sharp, its homologous package built for node.js by Lovell Fuller.
Note: bimg is still beta. Pull request and issues are highly appreciated
Prerequisites
- libvips v7.40.0+ (7.42.0+ recommended)
- C compatible compiler such as gcc 4.6+ or clang 3.0+
- Go 1.3+
Installation
go get -u gopkg.in/h2non/bimg.v0
libvips
Run the following script as sudo (supports OSX, Debian/Ubuntu, Redhat, Fedora, Amazon Linux):
curl -s https://raw.githubusercontent.com/lovell/sharp/master/preinstall.sh | sudo bash -
The install script requires curl and pkg-config
Supported image operations
- Resize
- Enlarge
- Crop
- Rotate
- Flip
- Thumbnail
- Extract area
- Format conversion
- EXIF metadata (size, alpha channel, profile, orientation...)
Performance
libvips is probably the faster open source solution for image processing. Here you can see some performance test comparisons for multiple scenarios:
bimg performance tests coming soon!
API
Examples
import (
"fmt"
"os"
"gopkg.in/h2non/bimg.v0"
)
Resize
buffer, err := bimg.Read("image.jpg")
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
newImage, err := bimg.NewImage(buffer).Resize(800, 600)
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
size, err := bimg.NewImage(newImage).Size()
if size.Width == 400 && size.Height == 300 {
fmt.Println("The image size is valid")
}
bimg.Write("new.jpg", newImage)
Rotate
buffer, err := bimg.Read("image.jpg")
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
newImage, err := bimg.NewImage(buffer).Rotate(90)
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
bimg.Write("new.jpg", newImage)
Convert
buffer, err := bimg.Read("image.jpg")
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
newImage, err := bimg.NewImage(buffer).Convert(bimg.PNG)
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
if bimg.NewImage(newImage).Type() == "png" {
fmt.Fprintln(os.Stderr, "The image was converted into png")
}
Custom options
See Options struct to discover all the available fields
options := bimg.Options{
Width: 800,
Height: 600,
Crop: true,
Quality: 95,
Rotate: 180,
}
buffer, err := bimg.Read("image.jpg")
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
newImage, err := bimg.NewImage(buffer).Process(options)
if err != nil {
fmt.Fprintln(os.Stderr, err)
}
bimg.Write("new.jpg", newImage)
func DetermineImageTypeName
func DetermineImageTypeName(buf []byte) string
func Initialize
func Initialize()
func IsTypeNameSupported
func IsTypeNameSupported(t string) bool
func IsTypeSupported
func IsTypeSupported(t ImageType) bool
func Read
func Read(path string) ([]byte, error)
func Resize
func Resize(buf []byte, o Options) ([]byte, error)
func Shutdown
func Shutdown()
type Angle
type Angle int
const (
D0 Angle = C.VIPS_ANGLE_D0
D90 Angle = C.VIPS_ANGLE_D90
D180 Angle = C.VIPS_ANGLE_D180
D270 Angle = C.VIPS_ANGLE_D270
)
type Direction
type Direction int
const (
HORIZONTAL Direction = C.VIPS_DIRECTION_HORIZONTAL
VERTICAL Direction = C.VIPS_DIRECTION_VERTICAL
)
type Gravity
type Gravity int
const (
CENTRE Gravity = iota
NORTH
EAST
SOUTH
WEST
)
type Image
type Image struct {
}
func NewImage
func NewImage(buf []byte) *Image
func (*Image) Convert
func (i *Image) Convert(t ImageType) ([]byte, error)
func (*Image) Crop
func (i *Image) Crop(width int, height int) ([]byte, error)
func (*Image) Extract
func (i *Image) Extract(top int, left int, width int, height int) ([]byte, error)
func (*Image) Flip
func (i *Image) Flip() ([]byte, error)
func (*Image) Flop
func (i *Image) Flop() ([]byte, error)
func (*Image) Metadata
func (i *Image) Metadata() (ImageMetadata, error)
func (*Image) Process
func (i *Image) Process(o Options) ([]byte, error)
func (*Image) Resize
func (i *Image) Resize(width int, height int) ([]byte, error)
func (*Image) Rotate
func (i *Image) Rotate(a Angle) ([]byte, error)
func (*Image) Size
func (i *Image) Size() (ImageSize, error)
func (*Image) Type
func (i *Image) Type() string
type ImageMetadata
type ImageMetadata struct {
Orientation int
Alpha bool
Profile bool
Space int
Type string
Size ImageSize
}
func Metadata
func Metadata(buf []byte) (ImageMetadata, error)
type ImageSize
type ImageSize struct {
Width int
Height int
}
func Size
func Size(buf []byte) (ImageSize, error)
type ImageType
type ImageType int
const (
UNKNOWN ImageType = iota
JPEG
WEBP
PNG
TIFF
MAGICK
)
func DetermineImageType
func DetermineImageType(buf []byte) ImageType
type Interpolator
type Interpolator int
const (
BICUBIC Interpolator = iota
BILINEAR
NOHALO
)
func (Interpolator) String
func (i Interpolator) String() string
type Options
type Options struct {
Height int
Width int
Top int
Left int
Crop bool
Enlarge bool
Extend int
Embed bool
Quality int
Compression int
Type ImageType
Rotate Angle
Flip Direction
Gravity Gravity
Interpolator Interpolator
}
License
MIT - Tomas Aparicio