完成基础版GIF生成,待调优

image/define.go

@@ -0,0 +1,29 @@
+// Package image ...
+//
+// Description : image ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2021-11-29 2:27 下午
+package image
+
+const (
+	// TypeGIF ...
+	TypeGIF = "gif"
+	// TypePNG ...
+	TypePNG = "png"
+	// TypeJPG ...
+	TypeJPG = "jpg"
+	// TypeJPEG ...
+	TypeJPEG = "jpeg"
+)
+
+// ImgInfo ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2:45 下午 2021/11/29
+type ImgInfo struct {
+	Path string
+	Type string
+}

image/gif.go

@@ -0,0 +1,195 @@
+// Package image ...
+//
+// Description : GIF相关操作
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2021-11-29 12:43 下午
+package image
+
+import (
+	"errors"
+	"image"
+	"image/color"
+	"image/color/palette"
+	"image/draw"
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"os"
+
+	"git.zhangdeman.cn/zhangdeman/gopkg/util"
+)
+
+var (
+	// GIF ...
+	GIF *GIFConvert
+)
+
+func init() {
+	GIF = &GIFConvert{}
+}
+
+// GIFConvert gif转换
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 12:44 下午 2021/11/29
+type GIFConvert struct {
+}
+
+// Generate 生成
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2:13 下午 2021/11/29
+func (g *GIFConvert) Generate(sourceImageList []string, savePath string) error {
+	if len(sourceImageList) == 0 {
+		return errors.New("source image list is empty")
+	}
+	var (
+		err           error
+		formatImgList []ImgInfo
+		disposals     []byte
+		images        []*image.Paletted
+		// 播放速度设置 , 100 次多少秒
+		delays []int
+	)
+	if formatImgList, err = g.checkImageType(sourceImageList); nil != err {
+		return err
+	}
+
+	for _, imgInfo := range formatImgList {
+		img, gErr := g.loadImage(imgInfo)
+		if nil != gErr {
+			return gErr
+		}
+		cp := g.getPalette(img)
+		//cp:=append(palette.WebSafe,color.Transparent)
+		disposals = append(disposals, gif.DisposalBackground) //透明图片需要设置
+		p := image.NewPaletted(image.Rect(0, 0, 640, 996), cp)
+		draw.Draw(p, p.Bounds(), img, image.ZP, draw.Src)
+		images = append(images, p)
+		delays = append(delays, 100)
+	}
+	gifInstance := &gif.GIF{
+		Image:     images,
+		Delay:     delays,
+		LoopCount: -1,
+		Disposal:  disposals,
+	}
+	f, fErr := os.Create(savePath)
+	if fErr != nil {
+		return fErr
+	}
+	defer func() { _ = f.Close() }()
+	return gif.EncodeAll(f, gifInstance)
+}
+
+// checkImageType 检测图片类型
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2:16 下午 2021/11/29
+func (g *GIFConvert) checkImageType(sourceImageList []string) ([]ImgInfo, error) {
+	result := make([]ImgInfo, 0)
+	for _, item := range sourceImageList {
+		imgType := util.GetFileType(item)
+		if len(imgType) == 0 {
+			return result, errors.New(item + " parse img type fail!")
+		}
+		result = append(result, ImgInfo{
+			Path: item,
+			Type: imgType,
+		})
+	}
+	return result, nil
+}
+
+// loadImage 加载图片内容
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2:52 下午 2021/11/29
+func (g *GIFConvert) loadImage(imgInfo ImgInfo) (image.Image, error) {
+	var (
+		err error
+		f   *os.File
+	)
+	if f, err = os.Open(imgInfo.Path); nil != err {
+		return nil, err
+	}
+
+	defer func() {
+		_ = f.Close()
+	}()
+
+	switch imgInfo.Type {
+	case TypePNG:
+		if img, imgErr := png.Decode(f); nil != err {
+			return nil, imgErr
+		} else {
+			return img, nil
+		}
+	case TypeJPEG:
+		fallthrough
+	case TypeJPG:
+		if img, imgErr := jpeg.Decode(f); nil != err {
+			return nil, imgErr
+		} else {
+			return img, nil
+		}
+	case TypeGIF:
+		if img, imgErr := gif.Decode(f); nil != err {
+			return nil, imgErr
+		} else {
+			return img, nil
+		}
+	default:
+		return nil, errors.New(imgInfo.Type + " is not support!")
+	}
+}
+
+// getPalette ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 3:01 下午 2021/11/29
+func (g *GIFConvert) getPalette(m image.Image) color.Palette {
+	p := color.Palette{color.RGBA{0x00, 0x00, 0x00, 0x00}}
+	p9 := color.Palette(palette.Plan9)
+	b := m.Bounds()
+	black := false
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			c := m.At(x, y)
+			cc := p9.Convert(c)
+			if cc == p9[0] {
+				black = true
+			}
+			if g.isInPalette(p, cc) == -1 {
+				p = append(p, cc)
+			}
+		}
+	}
+	if len(p) < 256 && black == true {
+		p[0] = color.RGBA{0x00, 0x00, 0x00, 0x00} // transparent
+		p = append(p, p9[0])
+	}
+	return p
+}
+
+// isInPalette ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 3:01 下午 2021/11/29
+func (g *GIFConvert) isInPalette(p color.Palette, c color.Color) int {
+	ret := -1
+	for i, v := range p {
+		if v == c {
+			return i
+		}
+	}
+	return ret
+}

image/gif_test.go

@@ -0,0 +1,24 @@
+// Package image ...
+//
+// Description : image ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2021-11-29 3:10 下午
+package image
+
+import (
+	"fmt"
+	"testing"
+)
+
+// TestGIFConvert_Generate ...
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 3:10 下午 2021/11/29
+func TestGIFConvert_Generate(t *testing.T) {
+	sourceImgList := []string{"./test/1.jpeg", "./test/2.jpeg", "./test/3.jpeg", "./test/4.jpeg"}
+	savePath := "./test/test.gif"
+	fmt.Println(GIF.Generate(sourceImgList, savePath))
+}

util/file.go

@@ -85,3 +85,16 @@ func IsFileExist(filePath string) (bool, bool) {
 	f, err := os.Stat(filePath)
 	return nil == err || os.IsExist(err), (nil == err || os.IsExist(err)) && !f.IsDir()
 }
+
+// GetFileType 获取文件类型
+//
+// Author : go_developer@163.com<白茶清欢>
+//
+// Date : 2:30 下午 2021/11/29
+func GetFileType(fileName string) string {
+	fileArr := strings.Split(fileName, ".")
+	if len(fileArr) < 2 {
+		return ""
+	}
+	return strings.ToLower(fileArr[len(fileArr)-1])
+}