init

cmd/main.go

@@ -0,0 +1,102 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"image"
+	_ "image/jpeg"
+	"image/png"
+	_ "image/png"
+	"imgdiff/pkg/imgdiff"
+	"log"
+	"os"
+	"sync"
+
+	"github.com/alexflint/go-arg"
+	. "github.com/logrusorgru/aurora"
+)
+
+func loadImages(filePathes ...string) []image.Image {
+	images := make([]image.Image, len(filePathes))
+
+	wg := sync.WaitGroup{}
+
+	for i, path := range filePathes {
+		wg.Add(1)
+
+		go func(i int, path string) {
+			file, err := os.Open(path)
+
+			defer file.Close()
+
+			if err != nil {
+				log.Fatalf("can't open image %s %s", path, err.Error())
+			}
+
+			image, _, err := image.Decode(file)
+
+			if err != nil {
+				log.Fatalf("can't decode image %s %s", path, err.Error())
+			}
+
+			images[i] = image
+
+			wg.Done()
+		}(i, path)
+	}
+
+	wg.Wait()
+
+	return images
+}
+
+func main() {
+	var args struct {
+		Threshold    float64 `arg:"-t,--threshold" help:"Color difference threshold (from 0 to 1). Less more precise." default:"0.1"`
+		DiffImage    bool    `arg:"--diff-image" help:"Render image to the diff output instead of transparent background." default:"false"`
+		FailOnLayout bool    `arg:"--fail-on-layout" help:"Do not compare images and produce output if images layout is different." default:"false"`
+		Base         string  `arg:"positional" help:"Base image."`
+		Compare      string  `arg:"positional" help:"Image to compare with."`
+		Output       string  `arg:"positional" help:"Output image path."`
+	}
+
+	arg.MustParse(&args)
+
+	images := loadImages(args.Base, args.Compare)
+
+	image1, image2 := images[0], images[1]
+
+	if args.FailOnLayout && !image1.Bounds().Eq(image2.Bounds()) {
+		fmt.Println(Red("Failure!").Bold(), "Images have different layout.")
+
+		os.Exit(2)
+	}
+
+	result := imgdiff.Diff(image1, image2, &imgdiff.Options{
+		Threshold: args.Threshold,
+		DiffImage: args.DiffImage,
+	})
+
+	if result.Equal {
+		fmt.Println(Green("Success!").Bold(), "Images are equal.")
+		return
+	}
+
+	enc := &png.Encoder{
+		CompressionLevel: png.BestSpeed,
+	}
+
+	f, _ := os.Create(args.Output)
+	defer f.Close()
+
+	writer := bufio.NewWriter(f)
+	defer writer.Flush()
+
+	enc.Encode(writer, result.Image)
+
+	fmt.Println(Red("Failure!").Bold(), "Images are different.")
+
+	fmt.Printf("Different pixels: %d\n", Red(result.DiffPixelsCount).Bold())
+
+	os.Exit(1)
+}

go.mod

@@ -0,0 +1,8 @@
+module imgdiff
+
+go 1.15
+
+require (
+	github.com/alexflint/go-arg v1.3.0 // indirect
+	github.com/logrusorgru/aurora v2.0.3+incompatible // indirect
+)

go.sum

@@ -0,0 +1,9 @@
+github.com/alexflint/go-arg v1.3.0 h1:UfldqSdFWeLtoOuVRosqofU4nmhI1pYEbT4ZFS34Bdo=
+github.com/alexflint/go-arg v1.3.0/go.mod h1:9iRbDxne7LcR/GSvEr7ma++GLpdIU1zrghf2y2768kM=
+github.com/alexflint/go-scalar v1.0.0 h1:NGupf1XV/Xb04wXskDFzS0KWOLH632W/EO4fAFi+A70=
+github.com/alexflint/go-scalar v1.0.0/go.mod h1:GpHzbCOZXEKMEcygYQ5n/aa4Aq84zbxjy3MxYW0gjYw=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/logrusorgru/aurora v2.0.3+incompatible h1:tOpm7WcpBTn4fjmVfgpQq0EfczGlG91VSDkswnjF5A8=
+github.com/logrusorgru/aurora v2.0.3+incompatible/go.mod h1:7rIyQOR62GCctdiQpZ/zOJlFyk6y+94wXzv6RNZgaR4=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

pkg/imgdiff/imgdiff.go

@@ -0,0 +1,76 @@
+package imgdiff
+
+import (
+	"image"
+	"image/color"
+	"imgdiff/pkg/yiq"
+	"runtime"
+	"sync"
+	"sync/atomic"
+)
+
+// Options struct.
+type Options struct {
+	Threshold float64
+	DiffImage bool
+}
+
+// Result struct.
+type Result struct {
+	Equal           bool
+	Image           image.Image
+	DiffPixelsCount uint64
+}
+
+// Diff between two images.
+func Diff(image1 image.Image, image2 image.Image, options *Options) *Result {
+	diffPixelsCount := uint64(0)
+
+	maxDelta := yiq.MaxDelta * options.Threshold * options.Threshold
+
+	diff := image.NewNRGBA(image1.Bounds())
+
+	wg := sync.WaitGroup{}
+
+	cpus := runtime.NumCPU()
+
+	for i := 0; i < cpus; i++ {
+		wg.Add(1)
+
+		go func(i int) {
+			diffPixelsCounter := 0
+
+			for y := i; y <= image1.Bounds().Max.Y; y += cpus {
+				for x := 0; x <= image1.Bounds().Max.X; x++ {
+					pixel1, pixel2 := image1.At(x, y), image2.At(x, y)
+
+					if pixel1 != pixel2 {
+						delta := yiq.Delta(pixel1, pixel2)
+
+						if delta > maxDelta {
+							diff.SetNRGBA(x, y, color.NRGBA{R: 255, G: 0, B: 0, A: 255})
+
+							diffPixelsCounter++
+						}
+					} else if options.DiffImage {
+						diff.Set(x, y, pixel1)
+					}
+				}
+			}
+
+			if diffPixelsCounter > 0 {
+				atomic.AddUint64(&diffPixelsCount, uint64(diffPixelsCounter))
+			}
+
+			wg.Done()
+		}(i)
+	}
+
+	wg.Wait()
+
+	return &Result{
+		Equal:           diffPixelsCount == 0,
+		DiffPixelsCount: diffPixelsCount,
+		Image:           diff,
+	}
+}

pkg/yiq/delta.go

@@ -0,0 +1,38 @@
+package yiq
+
+import (
+	"image/color"
+)
+
+func normalize(rgba color.Color) (uint8, uint8, uint8, uint8) {
+	r, g, b, a := rgba.RGBA()
+
+	return uint8(r), uint8(g), uint8(b), uint8(a)
+}
+
+func rgb2y(r, g, b uint8) float64 {
+	return float64(r)*0.29889531 + float64(g)*0.58662247 + float64(b)*0.11448223
+}
+
+func rgb2i(r, g, b uint8) float64 {
+	return float64(r)*0.59597799 - float64(g)*0.27417610 - float64(b)*0.32180189
+}
+
+func rgb2q(r, g, b uint8) float64 {
+	return float64(r)*0.21147017 - float64(g)*0.52261711 + float64(b)*0.31114694
+}
+
+// Delta between two pixels.
+func Delta(pixelA, pixelB color.Color) float64 {
+	r1, g1, b1, _ := normalize(pixelA)
+	r2, g2, b2, _ := normalize(pixelB)
+
+	y := rgb2y(r1, g1, b1) - rgb2y(r2, g2, b2)
+	i := rgb2i(r1, g1, b1) - rgb2i(r2, g2, b2)
+	q := rgb2q(r1, g1, b1) - rgb2q(r2, g2, b2)
+
+	return 0.5053*y*y + 0.299*i*i + 0.1957*q*q
+}
+
+// MaxDelta is a max value of Delta func.
+var MaxDelta = 35215.0

readme.md

@@ -0,0 +1,47 @@
+# imgdiff
+
+Faster than [the fastest in the world pixel-by-pixel image difference tool](https://github.com/dmtrKovalenko/odiff).
+
+## Why?
+
+imgdiff isn't as fast as a tool like this should be and I'm not proud of it, but it is 3X faster than
+[the fastest in the world pixel-by-pixel image difference tool](https://github.com/dmtrKovalenko/odiff),
+so maybe you'll find it useful.
+
+## Features
+
+It can do everything [odiff](https://github.com/dmtrKovalenko/odiff) can. Faster.
+
+## Benchmarks
+
+[Cypress image](https://github.com/dmtrKovalenko/odiff/blob/main/images/www.cypress.io.png) 3446 x 10728
+
+| Command                                                        |      Mean [s] | Min [s] | Max [s] | Relative |
+| :------------------------------------------------------------- | ------------: | ------: | ------: | -------: |
+| `imgdiff images/cypress-1.png images/cypress-2.png output.png` | 1.442 ± 0.012 |   1.420 |   1.462 |     1.00 |
+| `odiff images/cypress-1.png images/cypress-2.png output.png`   | 6.475 ± 0.092 |   6.300 |   6.583 |     4.49 |
+
+[Water image](https://github.com/dmtrKovalenko/odiff/blob/main/images/water-4k.png) 8400 x 4725
+
+| Command                                                    |       Mean [s] | Min [s] | Max [s] | Relative |
+| :--------------------------------------------------------- | -------------: | ------: | ------: | -------: |
+| `imgdiff images/water-1.png images/water-2.png output.png` | 1.908 ± 0.0058 |   1.841 |   2.002 |     1.00 |
+| `odiff images/water-1.png images/water-2.png output.png`   |  6.016 ± 0.415 |   5.643 |   7.140 |     3.15 |
+
+## Usage
+
+```
+Usage: imgdiff [--threshold THRESHOLD] [--diff-image] [--fail-on-layout] BASE COMPARE OUTPUT
+
+Positional arguments:
+  BASE                   Base image.
+  COMPARE                Image to compare with.
+  OUTPUT                 Output image path.
+
+Options:
+  --threshold THRESHOLD, -t THRESHOLD
+                         Color difference threshold (from 0 to 1). Less more precise. [default: 0.1]
+  --diff-image           Render image to the diff output instead of transparent background. [default: false]
+  --fail-on-layout       Do not compare images and produce output if images layout is different. [default: false]
+  --help, -h             display this help and exit
+```

scripts/build.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+package_name=imgdiff
+
+platforms=("windows/amd64" "windows/386" "linux/386" "linux/amd64" "darwin/amd64")
+
+for platform in "${platforms[@]}"
+do
+    platform_split=(${platform//\// })
+    GOOS=${platform_split[0]}
+    GOARCH=${platform_split[1]}
+    output_name=$package_name'-'$GOOS'-'$GOARCH
+    if [ $GOOS = "windows" ]; then
+        output_name+='.exe'
+    fi
+
+    env GOOS=$GOOS GOARCH=$GOARCH go build -o $output_name cmd/main.go
+    if [ $? -ne 0 ]; then
+        echo 'An error has occurred! Aborting the script execution...'
+        exit 1
+    fi
+done