midec

Pure go multi-image detector. cf. Animated GIF, APNG, Animated WebP, Animated HEIF / AVIF.

Checks whether the image is a multi-image(animated image).

Usage

package main 

import (
	"fmt"
	"os"

	"github.com/sapphi-red/midec"
	_ "github.com/sapphi-red/midec/gif" // import this to detect Animated GIF
	// _ "github.com/sapphi-red/midec/png" // import this to detect APNG
	// _ "github.com/sapphi-red/midec/webp" // import this to detect Animated WebP
	// _ "github.com/sapphi-red/midec/isobmff" // import this to detect Animated HEIF / AVIF
)

func main() {
	fp, err := os.Open("test.gif")
	if err != nil {
		panic(err)
	}

	isAnimated := midec.IsAnimated(fp)
	fmt.Println(isAnimated)
}

Extension

To add support for other formats, use midec.RegisterFormat. This function is very similar to image.RegisterFormat.

func init() {
	midec.RegisterFormat("gif", gifHeader, isAnimated)
}

Benchmarks

Comparison with using image/gif package's gif.decodeAll. See code for bench_test.go.

goos: windows
goarch: amd64
pkg: github.com/sapphi-red/midec
cpu: AMD Ryzen 7 3700X 8-Core Processor
BenchmarkGIF_ImageGIF-16            2581            443108 ns/op          497567 B/op            1435 allocs/op
BenchmarkGIF_Midec-16             157585              7568 ns/op            5008 B/op              36 allocs/op
BenchmarkPNG_Midec-16             265256              4811 ns/op            5008 B/op              13 allocs/op
BenchmarkWebP_Midec-16            181000              6667 ns/op            5040 B/op              20 allocs/op
BenchmarkHEIFAVIF_Midec-16        188468              5967 ns/op            5136 B/op              44 allocs/op
PASS
ok      github.com/sapphi-red/midec     23.147s