package thumb import ( "errors" "fmt" "image" "image/gif" "image/jpeg" "image/png" "io" "path/filepath" "strings" model "github.com/cloudreve/Cloudreve/v3/models" "github.com/cloudreve/Cloudreve/v3/pkg/util" //"github.com/nfnt/resize" "golang.org/x/image/draw" ) // Thumb 缩略图 type Thumb struct { src image.Image ext string } // NewThumbFromFile 从文件数据获取新的Thumb对象, // 尝试通过文件名name解码图像 func NewThumbFromFile(file io.Reader, name string) (*Thumb, error) { ext := strings.ToLower(filepath.Ext(name)) // 无扩展名时 if len(ext) == 0 { return nil, errors.New("未知的图像类型") } var err error var img image.Image switch ext[1:] { case "jpg": img, err = jpeg.Decode(file) case "jpeg": img, err = jpeg.Decode(file) case "gif": img, err = gif.Decode(file) case "png": img, err = png.Decode(file) default: return nil, errors.New("未知的图像类型") } if err != nil { return nil, err } return &Thumb{ src: img, ext: ext[1:], }, nil } // GetThumb 生成给定最大尺寸的缩略图 func (image *Thumb) GetThumb(width, height uint) { //image.src = resize.Thumbnail(width, height, image.src, resize.Lanczos3) image.src = Thumbnail(width, height, image.src) } // GetSize 获取图像尺寸 func (image *Thumb) GetSize() (int, int) { b := image.src.Bounds() return b.Max.X, b.Max.Y } // Save 保存图像到给定路径 func (image *Thumb) Save(path string) (err error) { out, err := util.CreatNestedFile(path) if err != nil { return err } defer out.Close() switch model.GetSettingByNameWithDefault("thumb_encode_method", "jpg") { case "png": err = png.Encode(out, image.src) default: err = jpeg.Encode(out, image.src, &jpeg.Options{Quality: model.GetIntSetting("thumb_encode_quality", 85)}) } return err } // Thumbnail will downscale provided image to max width and height preserving // original aspect ratio and using the interpolation function interp. // It will return original image, without processing it, if original sizes // are already smaller than provided constraints. func Thumbnail(maxWidth, maxHeight uint, img image.Image) image.Image { origBounds := img.Bounds() origWidth := uint(origBounds.Dx()) origHeight := uint(origBounds.Dy()) newWidth, newHeight := origWidth, origHeight // Return original image if it have same or smaller size as constraints if maxWidth >= origWidth && maxHeight >= origHeight { return img } // Preserve aspect ratio if origWidth > maxWidth { newHeight = uint(origHeight * maxWidth / origWidth) if newHeight < 1 { newHeight = 1 } newWidth = maxWidth } if newHeight > maxHeight { newWidth = uint(newWidth * maxHeight / newHeight) if newWidth < 1 { newWidth = 1 } newHeight = maxHeight } return Resize(newWidth, newHeight, img) } func Resize(newWidth, newHeight uint, img image.Image) image.Image { // Set the expected size that you want: dst := image.NewRGBA(image.Rect(0, 0, int(newWidth), int(newHeight))) // Resize: draw.BiLinear.Scale(dst, dst.Rect, img, img.Bounds(), draw.Src, nil) return dst } // CreateAvatar 创建头像 func (image *Thumb) CreateAvatar(uid uint) error { // 读取头像相关设定 savePath := util.RelativePath(model.GetSettingByName("avatar_path")) s := model.GetIntSetting("avatar_size_s", 50) m := model.GetIntSetting("avatar_size_m", 130) l := model.GetIntSetting("avatar_size_l", 200) // 生成头像缩略图 src := image.src for k, size := range []int{s, m, l} { //image.src = resize.Resize(uint(size), uint(size), src, resize.Lanczos3) image.src = Resize(uint(size), uint(size), src) err := image.Save(filepath.Join(savePath, fmt.Sprintf("avatar_%d_%d.png", uid, k))) if err != nil { return err } } return nil }