Vipsgen – Go binding generator for libvips image processing library

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vipsgen is a Go binding generator for libvips - a fast and efficient image processing library.

Existing Go libvips bindings rely on manually written code that is often incomplete, error-prone, and difficult to maintain as libvips evolves. vipsgen aims to solve this problem by generating type-safe, robust, and fully documented Go bindings using GObject introspection.

vipsgen provides a pre-generated library you can import directly github.com/cshum/vipsgen/vips. Also allows code generation via vipsgen command that adapts to your specific libvips installation.

Coverage: Comprehensive bindings for around 300 libvips operations
Type-Safe: Generates proper Go types for libvips enums and structs
Idiomatic: Creates clear Go style code that feels natural to use
Streaming: Includes VipsSource bindings with io.ReadCloser integration for streaming

Use homebrew to install vips and pkg-config:

brew install vips pkg-config

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

export CGO_CFLAGS_ALLOW="-Xpreprocessor"

Use the package directly:

go get -u github.com/cshum/vipsgen/vips

vipsgen provides rich options for fine-tuning image operations. Each operation can accept a nil value for default options, or customize optional arguments with specific option structs:

package main import ( "fmt" "log" "net/http" "github.com/cshum/vipsgen/vips" ) func main() { // Fetch an image from http.Get resp, err := http.Get("https://raw.githubusercontent.com/cshum/imagor/master/testdata/gopher.png") if err != nil { log.Fatalf("Failed to fetch image: %v", err) } defer resp.Body.Close() // Create source from io.ReadCloser source := vips.NewSource(resp.Body) defer source.Close() // source needs to remain available during image lifetime // Shrink-on-load via creating image from thumbnail source with options image, err := vips.NewThumbnailSource(source, 800, &vips.ThumbnailSourceOptions{ Height: 1000, FailOn: vips.FailOnError, // Fail on first error }) if err != nil { log.Fatalf("Failed to load image: %v", err) } defer image.Close() // always close images to free memory // Add a yellow border using vips_embed border := 10 if err := image.Embed( border, border, image.Width()+border*2, image.Height()+border*2, &vips.EmbedOptions{ Extend: vips.ExtendBackground, // extend with colour from the background property Background: []float64{255, 255, 0, 255}, // Yellow border }, ); err != nil { log.Fatalf("Failed to add border: %v", err) } fmt.Printf("Processed image: %dx%d\n", image.Width(), image.Height()) // Save the result as WebP file with options err = image.Webpsave("resized-gopher.webp", &vips.WebpsaveOptions{ Q: 85, // Quality factor (0-100) Effort: 4, // Compression effort (0-6) SmartSubsample: true, // Better chroma subsampling }) if err != nil { log.Fatalf("Failed to save image as WebP: %v", err) } fmt.Println("Successfully saved processed images") }

Code generation requires libvips to be built with GObject introspection support.

go install github.com/cshum/vipsgen/cmd/vipsgen@latest

Generate the bindings:

Use your custom-generated code:

package main import ( "yourproject/vips" )

Usage: vipsgen [options] Options: -out string Output directory (default "./out") -templates string Template directory (uses embedded templates if not specified) -extract Extract embedded templates and exit -extract-dir string Directory to extract templates to (default "./templates") -debug Enable debug json output

Contributions are welcome! Please feel free to submit a Pull Request.

MIT

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