package crop import ( "bytes" "fmt" "image" "os" "path" "path/filepath" "strings" "github.com/disintegration/imaging" "github.com/photoprism/photoprism/internal/thumb" "github.com/photoprism/photoprism/pkg/fs" "github.com/photoprism/photoprism/pkg/sanitize" ) // Filenames of usable thumb sizes. var thumbFileNames = []string{ "%s_720x720_fit.jpg", "%s_1280x1024_fit.jpg", "%s_1920x1200_fit.jpg", "%s_2048x2048_fit.jpg", "%s_4096x4096_fit.jpg", "%s_7680x4320_fit.jpg", } // Suitable thumb file sizes. var thumbFileSizes = []thumb.Size{ thumb.Sizes[thumb.Fit720], thumb.Sizes[thumb.Fit1280], thumb.Sizes[thumb.Fit1920], thumb.Sizes[thumb.Fit2048], thumb.Sizes[thumb.Fit4096], thumb.Sizes[thumb.Fit7680], } // ImageFromThumb returns a cropped area from an existing thumbnail image. func ImageFromThumb(thumbName string, area Area, size Size, cache bool) (img image.Image, err error) { // Use same folder for caching if "cache" is true. filePath := filepath.Dir(thumbName) // Extract hash from file name. hash := thumbHash(thumbName) // Compose cached crop image file name. cropBase := fmt.Sprintf("%s_%dx%d_crop_%s%s", hash, size.Width, size.Height, area.String(), fs.JpegExt) cropName := filepath.Join(filePath, cropBase) // Cached? if !fs.FileExists(cropName) { // Do nothing. } else if img, err := imaging.Open(cropName); err != nil { log.Errorf("crop: failed loading %s", filepath.Base(cropName)) } else { return img, nil } // Open thumb image file. img, err = openIdealThumbFile(thumbName, hash, area, size) if err != nil { return img, err } // Get absolute crop coordinates and dimension. min, max, dim := area.Bounds(img) if dim < size.Width { log.Debugf("crop: %s is too small, upscaling %dpx to %dpx", filepath.Base(thumbName), dim, size.Width) } // Crop area from image. img = imaging.Crop(img, image.Rect(min.X, min.Y, max.X, max.Y)) // Resample crop area. img = thumb.Resample(img, size.Width, size.Height, size.Options...) // Cache crop image? if cache { if err := imaging.Save(img, cropName); err != nil { log.Errorf("crop: failed caching %s", filepath.Base(cropName)) } else { log.Debugf("crop: saved %s", filepath.Base(cropName)) } } return img, nil } // ThumbFileName returns the ideal thumb file name. func ThumbFileName(hash string, area Area, size Size, thumbPath string) (string, error) { if len(hash) < 4 { return "", fmt.Errorf("invalid file hash %s", sanitize.Log(hash)) } if len(thumbPath) < 1 { return "", fmt.Errorf("cache path missing") } if area.W <= 0 { return "", fmt.Errorf("invalid area width %f", area.W) } if size.Width <= 0 { return "", fmt.Errorf("invalid crop size %d", size.Width) } filePath := path.Join(thumbPath, hash[0:1], hash[1:2], hash[2:3]) fileName := findIdealThumbFileName(hash, area.FileWidth(size), filePath) if fileName == "" { return "", fmt.Errorf("not found") } return fileName, nil } // FileWidth returns the minimal thumbnail width based on crop area and size. func FileWidth(area Area, size Size) int { return int(float32(size.Width) / area.W) } // thumbHash returns the thumb filename base without extension and size. func thumbHash(fileName string) (base string) { base = filepath.Base(fileName) // Example: 01244519acf35c62a5fea7a5a7dcefdbec4fb2f5_1280x1024_fit.jpg i := strings.Index(base, "_") if i <= 0 { return fs.StripExt(base) } return base[:i] } // findIdealThumbFileName finds the filename of the ideal thumb size for the given width. func findIdealThumbFileName(hash string, width int, filePath string) (fileName string) { if hash == "" || filePath == "" { return "" } for i, s := range thumbFileSizes { name := filepath.Join(filePath, fmt.Sprintf(thumbFileNames[i], hash)) if !fs.FileExists(name) { continue } else if s.Width < width { fileName = name continue } else { return name } } return fileName } // openIdealThumbFile opens the thumbnail file and returns an image. func openIdealThumbFile(fileName, hash string, area Area, size Size) (image.Image, error) { if len(hash) != 40 || area.W <= 0 || size.Width <= 0 { // Not a standard thumb name with sha1 hash prefix. if imageBuffer, err := os.ReadFile(fileName); err != nil { return nil, err } else { return imaging.Decode(bytes.NewReader(imageBuffer), imaging.AutoOrientation(true)) } } if name := findIdealThumbFileName(hash, area.FileWidth(size), filepath.Dir(fileName)); name != "" { fileName = name } if imageBuffer, err := os.ReadFile(fileName); err != nil { return nil, err } else { return imaging.Decode(bytes.NewReader(imageBuffer)) } }