govips

A lightning fast image processing and resizing library for Go

Programming language: Go

License: MIT License

Tags: Images    

README

govips

A lightning fast image processing and resizing library for Go

This package wraps the core functionality of libvips image processing library by exposing all image operations on first-class types in Go.

Libvips is generally 4-8x faster than other graphics processors such as GraphicsMagick and ImageMagick. Check the benchmark: Speed and Memory Use

The intent for this is to enable developers to build extremely fast image processors in Go, which is suited well for concurrent requests.

Requirements

• libvips 8.10+
• C compatible compiler such as gcc 4.6+ or clang 3.0+
• Go 1.14+

Dependencies

MacOS

Use homebrew to install vips and pkg-config:

brew install vips pkg-config

Ubuntu

You need a recent libvips to work with govips. New govips functionality is continuously added which takes advantage of new libvips functionality. Groovy (20.10) and Hirsute (21.04) repositories have working versions. However on Focal (20.04), you need to install libvips and dependencies from a backports repository:

sudo add-apt-repository -y ppa:strukturag/libde265
sudo add-apt-repository -y ppa:strukturag/libheif
sudo add-apt-repository ppa:tonimelisma/ppa

Then:

sudo apt -y install libvips-dev

Windows

The recommended approach on Windows is to use Govips via WSL and Ubuntu.

If you need to run Govips natively on Windows, it's not difficult but will require some effort. We don't have a recommended environment or setup at the moment. Windows is also not in our list of CI/CD targets so Govips is not regularly tested for compatibility. If you would be willing to setup and maintain a robust CI/CD Windows environment, please open a PR, we would be pleased to accept your contribution and support Windows as a platform.

Installation

go get -u github.com/davidbyttow/govips/v2/vips

MacOS note

On MacOS, govips may not compile without first setting an environment variable:

export CGO_CFLAGS_ALLOW="-Xpreprocessor"

Example usage

package main

import (
    "fmt"
    "io/ioutil"
    "os"

    "github.com/davidbyttow/govips/v2/vips"
)

func checkError(err error) {
    if err != nil {
        fmt.Println("error:", err)
        os.Exit(1)
    }
}

func main() {
    vips.Startup(nil)
    defer vips.Shutdown()

    image1, err := vips.NewImageFromFile("input.jpg")
    checkError(err)

    // Rotate the picture upright and reset EXIF orientation tag
    err = image1.AutoRotate()
    checkError(err)

    ep := vips.NewDefaultJPEGExportParams()
    image1bytes, _, err := image1.Export(ep)
    err = ioutil.WriteFile("output.jpg", image1bytes, 0644)
    checkError(err)

}

See examples/ folder for more examples.

Running tests

$ make test

Memory usage note

MALLOC_ARENA_MAX

libvips uses GLib for memory management, and it brings GLib memory fragmentation issues to heavily multi-threaded programs. First thing you can try if you noticed constantly growing RSS usage without Go's sys memory growth is set MALLOC_ARENA_MAX:

MALLOC_ARENA_MAX=2 application

This will reduce GLib memory appetites by reducing the number of malloc arenas that it can create. By default GLib creates one are per thread, and this would follow to a memory fragmentation.

Contributing

Feel free to file issues or create pull requests. See this guide on contributing for more information.

Credits

Thanks to:

• John Cupitt for creating and maintaining libvips
• Toni Melisma for pushing to a 2.x release
• wix.com for the govips logo and lots of great functionality
• All of our fantastic contributors

License

MIT