diff --git a/internal/api/album.go b/internal/api/album.go
index 8308a3930..95f156fe3 100644
--- a/internal/api/album.go
+++ b/internal/api/album.go
@@ -12,9 +12,11 @@ import (
 
 	"github.com/photoprism/photoprism/internal/entity"
 	"github.com/photoprism/photoprism/internal/event"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/form"
-	"github.com/photoprism/photoprism/internal/photoprism"
 	"github.com/photoprism/photoprism/internal/query"
+	"github.com/photoprism/photoprism/internal/rnd"
+	"github.com/photoprism/photoprism/internal/thumb"
 
 	"github.com/gin-gonic/gin"
 	"github.com/gin-gonic/gin/binding"
@@ -339,7 +341,7 @@ func DownloadAlbum(router *gin.RouterGroup, conf *config.Config) {
 		}
 
 		zipPath := path.Join(conf.ExportPath(), "album")
-		zipToken := util.RandomToken(3)
+		zipToken := rnd.Token(3)
 		zipBaseName := fmt.Sprintf("%s-%s.zip", strings.Title(a.AlbumSlug), zipToken)
 		zipFileName := path.Join(zipPath, zipBaseName)
 
@@ -362,21 +364,21 @@ func DownloadAlbum(router *gin.RouterGroup, conf *config.Config) {
 		zipWriter := zip.NewWriter(newZipFile)
 		defer zipWriter.Close()
 
-		for _, file := range p {
-			fileName := path.Join(conf.OriginalsPath(), file.FileName)
-			fileAlias := file.DownloadFileName()
+		for _, f := range p {
+			fileName := path.Join(conf.OriginalsPath(), f.FileName)
+			fileAlias := f.DownloadFileName()
 
-			if util.Exists(fileName) {
+			if file.Exists(fileName) {
 				if err := addFileToZip(zipWriter, fileName, fileAlias); err != nil {
 					log.Error(err)
 					c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{"error": util.UcFirst("failed to create zip file")})
 					return
 				}
-				log.Infof("album: added \"%s\" as \"%s\"", file.FileName, fileAlias)
+				log.Infof("album: added \"%s\" as \"%s\"", f.FileName, fileAlias)
 			} else {
-				log.Warnf("album: \"%s\" is missing", file.FileName)
-				file.FileMissing = true
-				conf.Db().Save(&file)
+				log.Warnf("album: \"%s\" is missing", f.FileName)
+				f.FileMissing = true
+				conf.Db().Save(&f)
 			}
 		}
 
@@ -385,7 +387,7 @@ func DownloadAlbum(router *gin.RouterGroup, conf *config.Config) {
 		zipWriter.Close()
 		newZipFile.Close()
 
-		if !util.Exists(zipFileName) {
+		if !file.Exists(zipFileName) {
 			log.Errorf("could not find zip file: %s", zipFileName)
 			c.Data(404, "image/svg+xml", photoIconSvg)
 			return
@@ -411,7 +413,7 @@ func AlbumThumbnail(router *gin.RouterGroup, conf *config.Config) {
 		typeName := c.Param("type")
 		uuid := c.Param("uuid")
 
-		thumbType, ok := photoprism.ThumbnailTypes[typeName]
+		thumbType, ok := thumb.Types[typeName]
 
 		if !ok {
 			log.Errorf("invalid type: %s", typeName)
@@ -421,7 +423,7 @@ func AlbumThumbnail(router *gin.RouterGroup, conf *config.Config) {
 
 		q := query.New(conf.OriginalsPath(), conf.Db())
 
-		file, err := q.FindAlbumThumbByUUID(uuid)
+		f, err := q.FindAlbumThumbByUUID(uuid)
 
 		if err != nil {
 			log.Debugf("album has no photos yet, using generic thumb image: %s", uuid)
@@ -429,21 +431,21 @@ func AlbumThumbnail(router *gin.RouterGroup, conf *config.Config) {
 			return
 		}
 
-		fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-		if !util.Exists(fileName) {
+		if !file.Exists(fileName) {
 			log.Errorf("could not find original for thumbnail: %s", fileName)
 			c.Data(http.StatusNotFound, "image/svg+xml", photoIconSvg)
 
 			// Set missing flag so that the file doesn't show up in search results anymore
-			file.FileMissing = true
-			conf.Db().Save(&file)
+			f.FileMissing = true
+			conf.Db().Save(&f)
 			return
 		}
 
-		if thumbnail, err := photoprism.ThumbnailFromFile(fileName, file.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
+		if thumbnail, err := thumb.FromFile(fileName, f.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
 			if c.Query("download") != "" {
-				downloadFileName := file.DownloadFileName()
+				downloadFileName := f.DownloadFileName()
 
 				c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=%s", downloadFileName))
 			}
diff --git a/internal/api/batch.go b/internal/api/batch.go
index 907e8b919..aaa85b9a9 100644
--- a/internal/api/batch.go
+++ b/internal/api/batch.go
@@ -90,7 +90,6 @@ func BatchPhotosRestore(router *gin.RouterGroup, conf *config.Config) {
 	})
 }
 
-
 // POST /api/v1/batch/albums/delete
 func BatchAlbumsDelete(router *gin.RouterGroup, conf *config.Config) {
 	router.POST("/batch/albums/delete", func(c *gin.Context) {
diff --git a/internal/api/download.go b/internal/api/download.go
index b9e452282..2409a876d 100644
--- a/internal/api/download.go
+++ b/internal/api/download.go
@@ -5,8 +5,8 @@ import (
 	"path"
 
 	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/query"
-	"github.com/photoprism/photoprism/internal/util"
 
 	"github.com/gin-gonic/gin"
 )
@@ -24,26 +24,26 @@ func GetDownload(router *gin.RouterGroup, conf *config.Config) {
 		fileHash := c.Param("hash")
 
 		q := query.New(conf.OriginalsPath(), conf.Db())
-		file, err := q.FindFileByHash(fileHash)
+		f, err := q.FindFileByHash(fileHash)
 
 		if err != nil {
 			c.AbortWithStatusJSON(404, gin.H{"error": err.Error()})
 			return
 		}
 
-		fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-		if !util.Exists(fileName) {
+		if !file.Exists(fileName) {
 			log.Errorf("could not find original: %s", fileHash)
 			c.Data(404, "image/svg+xml", photoIconSvg)
 
 			// Set missing flag so that the file doesn't show up in search results anymore
-			file.FileMissing = true
-			conf.Db().Save(&file)
+			f.FileMissing = true
+			conf.Db().Save(&f)
 			return
 		}
 
-		downloadFileName := file.DownloadFileName()
+		downloadFileName := f.DownloadFileName()
 
 		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=%s", downloadFileName))
 
diff --git a/internal/api/import.go b/internal/api/import.go
index 459ad83bd..372384f3d 100644
--- a/internal/api/import.go
+++ b/internal/api/import.go
@@ -8,11 +8,10 @@ import (
 	"strings"
 	"time"
 
+	"github.com/gin-gonic/gin"
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/event"
-	"github.com/photoprism/photoprism/internal/util"
-
-	"github.com/gin-gonic/gin"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/photoprism"
 )
 
@@ -61,7 +60,7 @@ func StartImport(router *gin.RouterGroup, conf *config.Config) {
 
 		imp.Start(path)
 
-		if subPath != "" && path != conf.ImportPath() && util.DirectoryIsEmpty(path) {
+		if subPath != "" && path != conf.ImportPath() && file.IsEmpty(path) {
 			if err := os.Remove(path); err != nil {
 				log.Errorf("import: could not deleted empty directory \"%s\": %s", path, err)
 			} else {
diff --git a/internal/api/index.go b/internal/api/index.go
index fa65e038f..225c3906d 100644
--- a/internal/api/index.go
+++ b/internal/api/index.go
@@ -55,11 +55,6 @@ func StartIndexing(router *gin.RouterGroup, conf *config.Config) {
 			return
 		}
 
-		// Set thumbnails JPEG quality and size
-		photoprism.JpegQuality = conf.ThumbQuality()
-		photoprism.MaxThumbWidth = conf.ThumbSize()
-		photoprism.MaxThumbHeight = conf.ThumbSize()
-
 		path := conf.OriginalsPath()
 
 		event.Info(fmt.Sprintf("indexing photos in \"%s\"", filepath.Base(path)))
diff --git a/internal/api/label.go b/internal/api/label.go
index 1b2ea8d7d..75611c4e2 100644
--- a/internal/api/label.go
+++ b/internal/api/label.go
@@ -12,9 +12,10 @@ import (
 	"github.com/gin-gonic/gin/binding"
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/event"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/form"
-	"github.com/photoprism/photoprism/internal/photoprism"
 	"github.com/photoprism/photoprism/internal/query"
+	"github.com/photoprism/photoprism/internal/thumb"
 	"github.com/photoprism/photoprism/internal/util"
 )
 
@@ -123,7 +124,7 @@ func LabelThumbnail(router *gin.RouterGroup, conf *config.Config) {
 		labelUUID := c.Param("uuid")
 		start := time.Now()
 
-		thumbType, ok := photoprism.ThumbnailTypes[typeName]
+		thumbType, ok := thumb.Types[typeName]
 
 		if !ok {
 			log.Errorf("invalid type: %s", typeName)
@@ -142,7 +143,7 @@ func LabelThumbnail(router *gin.RouterGroup, conf *config.Config) {
 			return
 		}
 
-		file, err := q.FindLabelThumbByUUID(labelUUID)
+		f, err := q.FindLabelThumbByUUID(labelUUID)
 
 		if err != nil {
 			log.Errorf(err.Error())
@@ -150,19 +151,19 @@ func LabelThumbnail(router *gin.RouterGroup, conf *config.Config) {
 			return
 		}
 
-		fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-		if !util.Exists(fileName) {
+		if !file.Exists(fileName) {
 			log.Errorf("could not find original for thumbnail: %s", fileName)
 			c.Data(http.StatusOK, "image/svg+xml", labelIconSvg)
 
 			// Set missing flag so that the file doesn't show up in search results anymore
-			file.FileMissing = true
-			conf.Db().Save(&file)
+			f.FileMissing = true
+			conf.Db().Save(&f)
 			return
 		}
 
-		if thumbnail, err := photoprism.ThumbnailFromFile(fileName, file.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
+		if thumbnail, err := thumb.FromFile(fileName, f.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
 			thumbData, err := ioutil.ReadFile(thumbnail)
 
 			if err != nil {
diff --git a/internal/api/photo.go b/internal/api/photo.go
index 83fa7a819..293659161 100644
--- a/internal/api/photo.go
+++ b/internal/api/photo.go
@@ -7,6 +7,7 @@ import (
 
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/event"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/query"
 	"github.com/photoprism/photoprism/internal/util"
 
@@ -73,26 +74,26 @@ func UpdatePhoto(router *gin.RouterGroup, conf *config.Config) {
 func GetPhotoDownload(router *gin.RouterGroup, conf *config.Config) {
 	router.GET("/photos/:uuid/download", func(c *gin.Context) {
 		q := query.New(conf.OriginalsPath(), conf.Db())
-		file, err := q.FindFileByPhotoUUID(c.Param("uuid"))
+		f, err := q.FindFileByPhotoUUID(c.Param("uuid"))
 
 		if err != nil {
 			c.AbortWithStatusJSON(404, gin.H{"error": err.Error()})
 			return
 		}
 
-		fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-		if !util.Exists(fileName) {
+		if !file.Exists(fileName) {
 			log.Errorf("could not find original: %s", c.Param("uuid"))
 			c.Data(404, "image/svg+xml", photoIconSvg)
 
 			// Set missing flag so that the file doesn't show up in search results anymore
-			file.FileMissing = true
-			conf.Db().Save(&file)
+			f.FileMissing = true
+			conf.Db().Save(&f)
 			return
 		}
 
-		downloadFileName := file.DownloadFileName()
+		downloadFileName := f.DownloadFileName()
 
 		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=%s", downloadFileName))
 
diff --git a/internal/api/photo_thumbnail.go b/internal/api/photo_thumbnail.go
index a8927b9c5..e0fea45ec 100644
--- a/internal/api/photo_thumbnail.go
+++ b/internal/api/photo_thumbnail.go
@@ -5,12 +5,11 @@ import (
 	"net/http"
 	"path"
 
-	"github.com/photoprism/photoprism/internal/config"
-	"github.com/photoprism/photoprism/internal/query"
-	"github.com/photoprism/photoprism/internal/util"
-
 	"github.com/gin-gonic/gin"
-	"github.com/photoprism/photoprism/internal/photoprism"
+	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/file"
+	"github.com/photoprism/photoprism/internal/query"
+	"github.com/photoprism/photoprism/internal/thumb"
 )
 
 // GET /api/v1/thumbnails/:hash/:type
@@ -23,7 +22,7 @@ func GetThumbnail(router *gin.RouterGroup, conf *config.Config) {
 		fileHash := c.Param("hash")
 		typeName := c.Param("type")
 
-		thumbType, ok := photoprism.ThumbnailTypes[typeName]
+		thumbType, ok := thumb.Types[typeName]
 
 		if !ok {
 			log.Errorf("invalid type: %s", typeName)
@@ -32,28 +31,28 @@ func GetThumbnail(router *gin.RouterGroup, conf *config.Config) {
 		}
 
 		q := query.New(conf.OriginalsPath(), conf.Db())
-		file, err := q.FindFileByHash(fileHash)
+		f, err := q.FindFileByHash(fileHash)
 
 		if err != nil {
 			c.AbortWithStatusJSON(http.StatusNotFound, gin.H{"error": err.Error()})
 			return
 		}
 
-		fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-		if !util.Exists(fileName) {
+		if !file.Exists(fileName) {
 			log.Errorf("could not find original for thumbnail: %s", fileName)
 			c.Data(http.StatusNotFound, "image/svg+xml", photoIconSvg)
 
 			// Set missing flag so that the file doesn't show up in search results anymore
-			file.FileMissing = true
-			conf.Db().Save(&file)
+			f.FileMissing = true
+			conf.Db().Save(&f)
 			return
 		}
 
-		if thumbnail, err := photoprism.ThumbnailFromFile(fileName, file.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
+		if thumbnail, err := thumb.FromFile(fileName, f.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...); err == nil {
 			if c.Query("download") != "" {
-				downloadFileName := file.DownloadFileName()
+				downloadFileName := f.DownloadFileName()
 
 				c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=%s", downloadFileName))
 			}
diff --git a/internal/api/preview.go b/internal/api/preview.go
index edf069871..5d9e2a179 100644
--- a/internal/api/preview.go
+++ b/internal/api/preview.go
@@ -12,10 +12,10 @@ import (
 	"github.com/disintegration/imaging"
 	"github.com/gin-gonic/gin"
 	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/form"
-	"github.com/photoprism/photoprism/internal/photoprism"
 	"github.com/photoprism/photoprism/internal/query"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/thumb"
 )
 
 // GET /api/v1/preview
@@ -33,7 +33,7 @@ func GetPreview(router *gin.RouterGroup, conf *config.Config) {
 
 		previewFilename := fmt.Sprintf("%s/%s.jpg", thumbPath, t[6:8])
 
-		if util.Exists(previewFilename) {
+		if file.Exists(previewFilename) {
 			c.File(previewFilename)
 			return
 		}
@@ -60,22 +60,22 @@ func GetPreview(router *gin.RouterGroup, conf *config.Config) {
 		y := 0
 
 		preview := imaging.New(width, height, color.NRGBA{255, 255, 255, 255})
-		thumbType, _ := photoprism.ThumbnailTypes["tile_224"]
+		thumbType, _ := thumb.Types["tile_224"]
 
-		for _, file := range p {
-			fileName := path.Join(conf.OriginalsPath(), file.FileName)
+		for _, f := range p {
+			fileName := path.Join(conf.OriginalsPath(), f.FileName)
 
-			if !util.Exists(fileName) {
+			if !file.Exists(fileName) {
 				log.Errorf("could not find original for thumbnail: %s", fileName)
 				c.Data(http.StatusNotFound, "image/svg+xml", photoIconSvg)
 
 				// Set missing flag so that the file doesn't show up in search results anymore
-				file.FileMissing = true
-				conf.Db().Save(&file)
+				f.FileMissing = true
+				conf.Db().Save(&f)
 				return
 			}
 
-			thumbnail, err := photoprism.ThumbnailFromFile(fileName, file.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...)
+			thumbnail, err := thumb.FromFile(fileName, f.FileHash, conf.ThumbnailsPath(), thumbType.Width, thumbType.Height, thumbType.Options...)
 
 			if err != nil {
 				log.Error(err)
diff --git a/internal/api/zip.go b/internal/api/zip.go
index 8c702cf45..11c9c9ce9 100644
--- a/internal/api/zip.go
+++ b/internal/api/zip.go
@@ -11,8 +11,10 @@ import (
 	"time"
 
 	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/form"
 	"github.com/photoprism/photoprism/internal/query"
+	"github.com/photoprism/photoprism/internal/rnd"
 	"github.com/photoprism/photoprism/internal/util"
 
 	"github.com/gin-gonic/gin"
@@ -44,7 +46,7 @@ func CreateZip(router *gin.RouterGroup, conf *config.Config) {
 		}
 
 		zipPath := path.Join(conf.ExportPath(), "zip")
-		zipToken := util.RandomToken(3)
+		zipToken := rnd.Token(3)
 		zipYear := time.Now().Format("January-2006")
 		zipBaseName := fmt.Sprintf("Photos-%s-%s.zip", zipYear, zipToken)
 		zipFileName := path.Join(zipPath, zipBaseName)
@@ -68,21 +70,21 @@ func CreateZip(router *gin.RouterGroup, conf *config.Config) {
 		zipWriter := zip.NewWriter(newZipFile)
 		defer zipWriter.Close()
 
-		for _, file := range files {
-			fileName := path.Join(conf.OriginalsPath(), file.FileName)
-			fileAlias := file.DownloadFileName()
+		for _, f := range files {
+			fileName := path.Join(conf.OriginalsPath(), f.FileName)
+			fileAlias := f.DownloadFileName()
 
-			if util.Exists(fileName) {
+			if file.Exists(fileName) {
 				if err := addFileToZip(zipWriter, fileName, fileAlias); err != nil {
 					log.Error(err)
 					c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{"error": util.UcFirst("failed to create zip file")})
 					return
 				}
-				log.Infof("zip: added \"%s\" as \"%s\"", file.FileName, fileAlias)
+				log.Infof("zip: added \"%s\" as \"%s\"", f.FileName, fileAlias)
 			} else {
-				log.Warnf("zip: \"%s\" is missing", file.FileName)
-				file.FileMissing = true
-				conf.Db().Save(&file)
+				log.Warnf("zip: \"%s\" is missing", f.FileName)
+				f.FileMissing = true
+				conf.Db().Save(&f)
 			}
 		}
 
@@ -103,7 +105,7 @@ func DownloadZip(router *gin.RouterGroup, conf *config.Config) {
 
 		c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=%s", zipBaseName))
 
-		if !util.Exists(zipFileName) {
+		if !file.Exists(zipFileName) {
 			log.Errorf("could not find zip file: %s", zipFileName)
 			c.Data(404, "image/svg+xml", photoIconSvg)
 			return
diff --git a/internal/commands/commands.go b/internal/commands/commands.go
index 591f69b59..a93ec147e 100644
--- a/internal/commands/commands.go
+++ b/internal/commands/commands.go
@@ -12,14 +12,14 @@ import (
 	"syscall"
 
 	"github.com/photoprism/photoprism/internal/event"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/sevlyar/go-daemon"
 )
 
 var log = event.Log
 
 func childAlreadyRunning(filePath string) (pid int, running bool) {
-	if !util.Exists(filePath) {
+	if !file.Exists(filePath) {
 		return pid, false
 	}
 
diff --git a/internal/commands/start.go b/internal/commands/start.go
index ba669d6f6..1b0e83ef4 100644
--- a/internal/commands/start.go
+++ b/internal/commands/start.go
@@ -10,8 +10,8 @@ import (
 	"time"
 
 	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/photoprism/photoprism/internal/server"
-	"github.com/photoprism/photoprism/internal/util"
 	"github.com/sevlyar/go-daemon"
 	"github.com/urfave/cli"
 )
@@ -96,7 +96,7 @@ func startAction(ctx *cli.Context) error {
 		}
 
 		if child != nil {
-			if !util.Overwrite(conf.PIDFilename(), []byte(strconv.Itoa(child.Pid))) {
+			if !file.Overwrite(conf.PIDFilename(), []byte(strconv.Itoa(child.Pid))) {
 				log.Fatalf("failed writing process id to \"%s\"", conf.PIDFilename())
 			}
 
diff --git a/internal/commands/thumbnails.go b/internal/commands/thumbnails.go
index d5e59637e..96b598c55 100644
--- a/internal/commands/thumbnails.go
+++ b/internal/commands/thumbnails.go
@@ -32,10 +32,6 @@ func thumbnailsAction(ctx *cli.Context) error {
 
 	log.Infof("creating thumbnails in \"%s\"", conf.ThumbnailsPath())
 
-	photoprism.JpegQuality = conf.ThumbQuality()
-	photoprism.MaxThumbWidth = conf.ThumbSize()
-	photoprism.MaxThumbHeight = conf.ThumbSize()
-
 	if err := photoprism.CreateThumbnailsFromOriginals(conf.OriginalsPath(), conf.ThumbnailsPath(), ctx.Bool("force")); err != nil {
 		log.Error(err)
 		return err
diff --git a/internal/config/client.go b/internal/config/client.go
index fba57633a..b4e0cb966 100644
--- a/internal/config/client.go
+++ b/internal/config/client.go
@@ -6,7 +6,7 @@ import (
 
 	"github.com/photoprism/photoprism/internal/colors"
 	"github.com/photoprism/photoprism/internal/entity"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 )
 
 // HTTP client / Web UI config values
@@ -118,8 +118,8 @@ func (c *Config) ClientConfig() ClientConfig {
 		categories[i].Title = strings.Title(l.LabelName)
 	}
 
-	jsHash := util.Hash(c.HttpStaticBuildPath() + "/app.js")
-	cssHash := util.Hash(c.HttpStaticBuildPath() + "/app.css")
+	jsHash := file.Hash(c.HttpStaticBuildPath() + "/app.js")
+	cssHash := file.Hash(c.HttpStaticBuildPath() + "/app.css")
 
 	// Feature Flags
 	var flags []string
diff --git a/internal/config/config.go b/internal/config/config.go
index 8cff3f136..c9312a08f 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -10,6 +10,7 @@ import (
 	_ "github.com/jinzhu/gorm/dialects/sqlite"
 	gc "github.com/patrickmn/go-cache"
 	"github.com/photoprism/photoprism/internal/event"
+	"github.com/photoprism/photoprism/internal/thumb"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli"
 )
@@ -22,6 +23,15 @@ type Config struct {
 	config *Params
 }
 
+func init() {
+	for name, t := range thumb.Types {
+		if t.Public {
+			thumbnail := Thumbnail{Name: name, Width: t.Width, Height: t.Height}
+			Thumbnails = append(Thumbnails, thumbnail)
+		}
+	}
+}
+
 func initLogger(debug bool) {
 	log.SetFormatter(&logrus.TextFormatter{
 		DisableColors: false,
@@ -44,6 +54,10 @@ func NewConfig(ctx *cli.Context) *Config {
 
 	log.SetLevel(c.LogLevel())
 
+	thumb.JpegQuality = c.ThumbQuality()
+	thumb.MaxWidth = c.ThumbSize()
+	thumb.MaxHeight = c.ThumbSize()
+
 	return c
 }
 
@@ -180,17 +194,32 @@ func (c *Config) Workers() int {
 	return runtime.NumCPU()
 }
 
-// ThumbQuality returns the thumbnail jpeg quality setting (0-100).
+// ThumbQuality returns the thumbnail jpeg quality setting (25-100).
 func (c *Config) ThumbQuality() int {
+	if c.config.ThumbQuality > 100 {
+		return 100
+	}
+
+	if c.config.ThumbQuality < 25 {
+		return 25
+	}
+
 	return c.config.ThumbQuality
 }
 
-// ThumbSize returns the thumbnail size limit in pixels.
+// ThumbSize returns the thumbnail size limit in pixels (720-16384).
 func (c *Config) ThumbSize() int {
+	if c.config.ThumbSize > 16384 {
+		return 16384
+	}
+
+	if c.config.ThumbSize < 720 {
+		return 720
+	}
+
 	return c.config.ThumbSize
 }
 
-
 // GeoCodingApi returns the preferred geo coding api (none, osm or places).
 func (c *Config) GeoCodingApi() string {
 	switch c.config.GeoCodingApi {
diff --git a/internal/config/config_test.go b/internal/config/config_test.go
index 3f90b259b..c3894b682 100644
--- a/internal/config/config_test.go
+++ b/internal/config/config_test.go
@@ -3,7 +3,7 @@ package config
 import (
 	"testing"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -17,7 +17,7 @@ func TestNewConfig(t *testing.T) {
 
 	assert.IsType(t, new(Config), c)
 
-	assert.Equal(t, util.ExpandedFilename("../../assets"), c.AssetsPath())
+	assert.Equal(t, file.ExpandFilename("../../assets"), c.AssetsPath())
 	assert.False(t, c.Debug())
 	assert.False(t, c.ReadOnly())
 }
diff --git a/internal/config/db.go b/internal/config/db.go
index 6becf8b72..cf325ded3 100644
--- a/internal/config/db.go
+++ b/internal/config/db.go
@@ -138,6 +138,9 @@ func (c *Config) connectToDatabase(ctx context.Context) error {
 		}
 	}
 
+	db.LogMode(false)
+	db.SetLogger(log)
+
 	c.db = db
 	return err
 }
@@ -185,7 +188,7 @@ func (c *Config) ImportSQL(filename string) {
 			continue
 		}
 
-		var result struct {}
+		var result struct{}
 
 		err := q.Raw(stmt).Scan(&result).Error
 
diff --git a/internal/config/filenames.go b/internal/config/filenames.go
index 19210a545..7a34a22fd 100644
--- a/internal/config/filenames.go
+++ b/internal/config/filenames.go
@@ -5,7 +5,7 @@ import (
 	"os/exec"
 	"path/filepath"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 )
 
 func findExecutable(configBin, defaultBin string) (result string) {
@@ -19,7 +19,7 @@ func findExecutable(configBin, defaultBin string) (result string) {
 		result = path
 	}
 
-	if !util.Exists(result) {
+	if !file.Exists(result) {
 		result = ""
 	}
 
diff --git a/internal/config/flags.go b/internal/config/flags.go
index dad52fd6b..e6c6f5fca 100644
--- a/internal/config/flags.go
+++ b/internal/config/flags.go
@@ -227,13 +227,13 @@ var GlobalFlags = []cli.Flag{
 	},
 	cli.IntFlag{
 		Name:   "thumb-quality, q",
-		Usage:  "jpeg quality of thumbnails (0-100)",
+		Usage:  "jpeg quality of thumbnails (25-100)",
 		Value:  95,
 		EnvVar: "PHOTOPRISM_THUMB_QUALITY",
 	},
 	cli.IntFlag{
 		Name:   "thumb-size",
-		Usage:  "max thumbnail size in pixels",
+		Usage:  "max thumbnail size in pixels (720-16384)",
 		Value:  8192,
 		EnvVar: "PHOTOPRISM_THUMB_SIZE",
 	},
diff --git a/internal/config/params.go b/internal/config/params.go
index 752bded5b..f84b8eac2 100644
--- a/internal/config/params.go
+++ b/internal/config/params.go
@@ -8,7 +8,7 @@ import (
 
 	_ "github.com/jinzhu/gorm/dialects/mysql"
 	_ "github.com/jinzhu/gorm/dialects/sqlite"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/urfave/cli"
 	"gopkg.in/yaml.v2"
 )
@@ -87,7 +87,7 @@ func NewParams(ctx *cli.Context) *Params {
 	c.Name = ctx.App.Name
 	c.Copyright = ctx.App.Copyright
 	c.Version = ctx.App.Version
-	c.ConfigFile = util.ExpandedFilename(ctx.GlobalString("config-file"))
+	c.ConfigFile = file.ExpandFilename(ctx.GlobalString("config-file"))
 
 	if err := c.SetValuesFromFile(c.ConfigFile); err != nil {
 		log.Debug(err)
@@ -103,21 +103,21 @@ func NewParams(ctx *cli.Context) *Params {
 }
 
 func (c *Params) expandFilenames() {
-	c.ConfigPath = util.ExpandedFilename(c.ConfigPath)
-	c.ResourcesPath = util.ExpandedFilename(c.ResourcesPath)
-	c.AssetsPath = util.ExpandedFilename(c.AssetsPath)
-	c.CachePath = util.ExpandedFilename(c.CachePath)
-	c.OriginalsPath = util.ExpandedFilename(c.OriginalsPath)
-	c.ImportPath = util.ExpandedFilename(c.ImportPath)
-	c.ExportPath = util.ExpandedFilename(c.ExportPath)
-	c.SqlServerPath = util.ExpandedFilename(c.SqlServerPath)
-	c.PIDFilename = util.ExpandedFilename(c.PIDFilename)
-	c.LogFilename = util.ExpandedFilename(c.LogFilename)
+	c.ConfigPath = file.ExpandFilename(c.ConfigPath)
+	c.ResourcesPath = file.ExpandFilename(c.ResourcesPath)
+	c.AssetsPath = file.ExpandFilename(c.AssetsPath)
+	c.CachePath = file.ExpandFilename(c.CachePath)
+	c.OriginalsPath = file.ExpandFilename(c.OriginalsPath)
+	c.ImportPath = file.ExpandFilename(c.ImportPath)
+	c.ExportPath = file.ExpandFilename(c.ExportPath)
+	c.SqlServerPath = file.ExpandFilename(c.SqlServerPath)
+	c.PIDFilename = file.ExpandFilename(c.PIDFilename)
+	c.LogFilename = file.ExpandFilename(c.LogFilename)
 }
 
 // SetValuesFromFile uses a yaml config file to initiate the configuration entity.
 func (c *Params) SetValuesFromFile(fileName string) error {
-	if !util.Exists(fileName) {
+	if !file.Exists(fileName) {
 		return errors.New(fmt.Sprintf("config file not found: \"%s\"", fileName))
 	}
 
diff --git a/internal/config/params_test.go b/internal/config/params_test.go
index c7dafdae1..cd874dac7 100644
--- a/internal/config/params_test.go
+++ b/internal/config/params_test.go
@@ -3,7 +3,7 @@ package config
 import (
 	"testing"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -17,7 +17,7 @@ func TestNewParams(t *testing.T) {
 
 	assert.IsType(t, new(Params), c)
 
-	assert.Equal(t, util.ExpandedFilename("../../assets"), c.AssetsPath)
+	assert.Equal(t, file.ExpandFilename("../../assets"), c.AssetsPath)
 	assert.False(t, c.Debug)
 	assert.False(t, c.ReadOnly)
 }
diff --git a/internal/config/settings.go b/internal/config/settings.go
index 328ae3a8e..31dfde0ee 100644
--- a/internal/config/settings.go
+++ b/internal/config/settings.go
@@ -5,7 +5,7 @@ import (
 	"io/ioutil"
 	"os"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"gopkg.in/yaml.v2"
 )
 
@@ -20,7 +20,7 @@ func NewSettings() *Settings {
 
 // SetValuesFromFile uses a yaml config file to initiate the configuration entity.
 func (s *Settings) SetValuesFromFile(fileName string) error {
-	if !util.Exists(fileName) {
+	if !file.Exists(fileName) {
 		return fmt.Errorf("settings file not found: \"%s\"", fileName)
 	}
 
@@ -35,7 +35,7 @@ func (s *Settings) SetValuesFromFile(fileName string) error {
 
 // WriteValuesToFile uses a yaml config file to initiate the configuration entity.
 func (s *Settings) WriteValuesToFile(fileName string) error {
-	if !util.Exists(fileName) {
+	if !file.Exists(fileName) {
 		return fmt.Errorf("settings file not found: \"%s\"", fileName)
 	}
 
diff --git a/internal/config/test.go b/internal/config/test.go
index 3301c2a83..6ce132024 100644
--- a/internal/config/test.go
+++ b/internal/config/test.go
@@ -10,7 +10,8 @@ import (
 
 	_ "github.com/jinzhu/gorm/dialects/mysql"
 	_ "github.com/jinzhu/gorm/dialects/sqlite"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
+	"github.com/photoprism/photoprism/internal/thumb"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli"
 )
@@ -29,7 +30,7 @@ func testDataPath(assetsPath string) string {
 }
 
 func NewTestParams() *Params {
-	assetsPath := util.ExpandedFilename("../../assets")
+	assetsPath := file.ExpandFilename("../../assets")
 
 	testDataPath := testDataPath(assetsPath)
 
@@ -52,7 +53,7 @@ func NewTestParams() *Params {
 }
 
 func NewTestParamsError() *Params {
-	assetsPath := util.ExpandedFilename("../..")
+	assetsPath := file.ExpandFilename("../..")
 
 	testDataPath := testDataPath("../../assets")
 
@@ -93,6 +94,10 @@ func NewTestConfig() *Config {
 
 	c.ImportSQL(c.ExamplesPath() + "/fixtures.sql")
 
+	thumb.JpegQuality = c.ThumbQuality()
+	thumb.MaxWidth = c.ThumbSize()
+	thumb.MaxHeight = c.ThumbSize()
+
 	return c
 }
 
@@ -140,8 +145,8 @@ func (c *Config) RemoveTestData(t *testing.T) {
 }
 
 func (c *Config) DownloadTestData(t *testing.T) {
-	if util.Exists(TestDataZip) {
-		hash := util.Hash(TestDataZip)
+	if file.Exists(TestDataZip) {
+		hash := file.Hash(TestDataZip)
 
 		if hash != TestDataHash {
 			os.Remove(TestDataZip)
@@ -149,17 +154,17 @@ func (c *Config) DownloadTestData(t *testing.T) {
 		}
 	}
 
-	if !util.Exists(TestDataZip) {
+	if !file.Exists(TestDataZip) {
 		fmt.Printf("downloading latest test data zip file from %s\n", TestDataURL)
 
-		if err := util.Download(TestDataZip, TestDataURL); err != nil {
+		if err := file.Download(TestDataZip, TestDataURL); err != nil {
 			fmt.Printf("Download failed: %s\n", err.Error())
 		}
 	}
 }
 
 func (c *Config) UnzipTestData(t *testing.T) {
-	if _, err := util.Unzip(TestDataZip, testDataPath(c.AssetsPath())); err != nil {
+	if _, err := file.Unzip(TestDataZip, testDataPath(c.AssetsPath())); err != nil {
 		t.Logf("could not unzip test data: %s\n", err.Error())
 	}
 }
diff --git a/internal/config/test_test.go b/internal/config/test_test.go
index 371303847..83d39a305 100644
--- a/internal/config/test_test.go
+++ b/internal/config/test_test.go
@@ -4,7 +4,7 @@ import (
 	"testing"
 
 	"github.com/jinzhu/gorm"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/stretchr/testify/assert"
 	"github.com/urfave/cli"
 )
@@ -26,7 +26,7 @@ func TestNewTestParams(t *testing.T) {
 
 	assert.IsType(t, new(Params), c)
 
-	assert.Equal(t, util.ExpandedFilename("../../assets"), c.AssetsPath)
+	assert.Equal(t, file.ExpandFilename("../../assets"), c.AssetsPath)
 	assert.False(t, c.Debug)
 }
 
@@ -43,7 +43,7 @@ func TestNewTestParamsError(t *testing.T) {
 
 	assert.IsType(t, new(Params), c)
 
-	assert.Equal(t, util.ExpandedFilename("../.."), c.AssetsPath)
+	assert.Equal(t, file.ExpandFilename("../.."), c.AssetsPath)
 	assert.Equal(t, "../../assets/testdata/cache", c.CachePath)
 	assert.False(t, c.Debug)
 }
diff --git a/internal/entity/entity.go b/internal/entity/entity.go
index 6ba356a46..0514710b5 100644
--- a/internal/entity/entity.go
+++ b/internal/entity/entity.go
@@ -16,7 +16,7 @@ import (
 
 	"github.com/jinzhu/gorm"
 	"github.com/photoprism/photoprism/internal/event"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/rnd"
 )
 
 var log = event.Log
@@ -32,7 +32,7 @@ func ID(prefix rune) string {
 	result := make([]byte, 0, 17)
 	result = append(result, byte(prefix))
 	result = append(result, strconv.FormatInt(time.Now().UTC().Unix(), 36)[0:6]...)
-	result = append(result, util.RandomToken(10)...)
+	result = append(result, rnd.Token(10)...)
 
 	return string(result)
 }
diff --git a/internal/util/file.go b/internal/file/file.go
similarity index 81%
rename from internal/util/file.go
rename to internal/file/file.go
index a503759c2..bd020f2f3 100644
--- a/internal/util/file.go
+++ b/internal/file/file.go
@@ -1,4 +1,11 @@
-package util
+/*
+This package encapsulates file related constants and functions.
+
+Additional information can be found in our Developer Guide:
+
+https://github.com/photoprism/photoprism/wiki
+*/
+package file
 
 import (
 	"archive/zip"
@@ -9,8 +16,12 @@ import (
 	"os/user"
 	"path/filepath"
 	"strings"
+
+	"github.com/photoprism/photoprism/internal/event"
 )
 
+var log = event.Log
+
 // Returns true if file exists
 func Exists(filename string) bool {
 	info, err := os.Stat(filename)
@@ -30,7 +41,7 @@ func Overwrite(fileName string, data []byte) bool {
 }
 
 // Returns full path; ~ replaced with actual home directory
-func ExpandedFilename(filename string) string {
+func ExpandFilename(filename string) string {
 	if filename == "" {
 		return ""
 	}
@@ -50,32 +61,6 @@ func ExpandedFilename(filename string) string {
 	return result
 }
 
-// Extract Zip file in destination directory
-func Unzip(src, dest string) (fileNames []string, err error) {
-	r, err := zip.OpenReader(src)
-	if err != nil {
-		return fileNames, err
-	}
-
-	defer r.Close()
-
-	for _, f := range r.File {
-		// Skip directories like __OSX
-		if strings.HasPrefix(f.Name, "__") {
-			continue
-		}
-
-		fn, err := copyToFile(f, dest)
-		if err != nil {
-			return fileNames, err
-		}
-
-		fileNames = append(fileNames, fn)
-	}
-
-	return fileNames, nil
-}
-
 // copyToFile copies the zip file to destination
 // if the zip file is a directory, a directory is created at the destination.
 func copyToFile(f *zip.File, dest string) (fileName string, err error) {
@@ -151,7 +136,7 @@ func Download(filepath string, url string) error {
 	return nil
 }
 
-func DirectoryIsEmpty(path string) bool {
+func IsEmpty(path string) bool {
 	f, err := os.Open(path)
 
 	if err != nil {
diff --git a/internal/util/file_test.go b/internal/file/file_test.go
similarity index 79%
rename from internal/util/file_test.go
rename to internal/file/file_test.go
index 556430f5c..46c50cdca 100644
--- a/internal/util/file_test.go
+++ b/internal/file/file_test.go
@@ -1,4 +1,4 @@
-package util
+package file
 
 import (
 	"os"
@@ -29,19 +29,19 @@ func TestOverwrite(t *testing.T) {
 
 func TestExpandedFilename(t *testing.T) {
 	t.Run("test.jpg", func(t *testing.T) {
-		filename := ExpandedFilename("./testdata/test.jpg")
+		filename := ExpandFilename("./testdata/test.jpg")
 		assert.Contains(t, filename, "/testdata/test.jpg")
 		assert.IsType(t, "", filename)
 	})
 	t.Run("empty filename", func(t *testing.T) {
-		filename := ExpandedFilename("")
+		filename := ExpandFilename("")
 		assert.Equal(t, "", filename)
 		assert.IsType(t, "", filename)
 	})
 	t.Run("~ in filename", func(t *testing.T) {
 		usr, _ := user.Current()
 		expected := usr.HomeDir + "/test.jpg"
-		filename := ExpandedFilename("~/test.jpg")
+		filename := ExpandFilename("~/test.jpg")
 		assert.Equal(t, expected, filename)
 		assert.IsType(t, "", filename)
 	})
@@ -49,14 +49,14 @@ func TestExpandedFilename(t *testing.T) {
 
 func TestDirectoryIsEmpty(t *testing.T) {
 	t.Run("not empty path", func(t *testing.T) {
-		assert.Equal(t, false, DirectoryIsEmpty("./testdata"))
+		assert.Equal(t, false, IsEmpty("./testdata"))
 	})
 	t.Run("not existing path", func(t *testing.T) {
-		assert.Equal(t, false, DirectoryIsEmpty("./xxx"))
+		assert.Equal(t, false, IsEmpty("./xxx"))
 	})
 	t.Run("empty path", func(t *testing.T) {
 		os.Mkdir("./testdata/emptyDir", 0777)
 		defer os.RemoveAll("./testdata/emptyDir")
-		assert.Equal(t, true, DirectoryIsEmpty("./testdata/emptyDir"))
+		assert.Equal(t, true, IsEmpty("./testdata/emptyDir"))
 	})
 }
diff --git a/internal/util/hash.go b/internal/file/hash.go
similarity index 96%
rename from internal/util/hash.go
rename to internal/file/hash.go
index 64d061ffc..27f73711d 100644
--- a/internal/util/hash.go
+++ b/internal/file/hash.go
@@ -1,4 +1,4 @@
-package util
+package file
 
 import (
 	"crypto/sha1"
diff --git a/internal/util/hash_test.go b/internal/file/hash_test.go
similarity index 96%
rename from internal/util/hash_test.go
rename to internal/file/hash_test.go
index 25c7d4f40..d73c30a56 100644
--- a/internal/util/hash_test.go
+++ b/internal/file/hash_test.go
@@ -1,4 +1,4 @@
-package util
+package file
 
 import (
 	"testing"
diff --git a/internal/util/mime.go b/internal/file/mime.go
similarity index 97%
rename from internal/util/mime.go
rename to internal/file/mime.go
index c727faef7..141347d97 100644
--- a/internal/util/mime.go
+++ b/internal/file/mime.go
@@ -1,4 +1,4 @@
-package util
+package file
 
 import (
 	"net/http"
diff --git a/internal/util/mime_test.go b/internal/file/mime_test.go
similarity index 73%
rename from internal/util/mime_test.go
rename to internal/file/mime_test.go
index 2ee12d3a7..1a11b6225 100644
--- a/internal/util/mime_test.go
+++ b/internal/file/mime_test.go
@@ -1,4 +1,4 @@
-package util
+package file
 
 import (
 	"testing"
@@ -8,12 +8,12 @@ import (
 
 func TestMimeType(t *testing.T) {
 	t.Run("jpg", func(t *testing.T) {
-		filename := ExpandedFilename("./testdata/test.jpg")
+		filename := ExpandFilename("./testdata/test.jpg")
 		mimeType := MimeType(filename)
 		assert.Equal(t, "image/jpeg", mimeType)
 	})
 	t.Run("not existing filename", func(t *testing.T) {
-		filename := ExpandedFilename("./testdata/xxx.jpg")
+		filename := ExpandFilename("./testdata/xxx.jpg")
 		mimeType := MimeType(filename)
 		assert.Equal(t, "", mimeType)
 	})
diff --git a/internal/file/testdata/test.jpg b/internal/file/testdata/test.jpg
new file mode 100644
index 000000000..0c8c04edb
Binary files /dev/null and b/internal/file/testdata/test.jpg differ
diff --git a/internal/file/types.go b/internal/file/types.go
new file mode 100644
index 000000000..943a19f87
--- /dev/null
+++ b/internal/file/types.go
@@ -0,0 +1,97 @@
+package file
+
+import (
+	_ "image/gif" // Import for image.
+	_ "image/jpeg"
+	_ "image/png"
+)
+
+type Type string
+
+const (
+	// JPEG image file.
+	TypeJpeg Type = "jpg"
+	// PNG image file.
+	TypePng Type = "png"
+	// RAW image file.
+	TypeRaw Type = "raw"
+	// High Efficiency Image File Format.
+	TypeHEIF Type = "heif" // High Efficiency Image File Format
+	// Movie file.
+	TypeMovie Type = "mov"
+	// Adobe XMP sidecar file (XML).
+	TypeXMP Type = "xmp"
+	// Apple sidecar file (XML).
+	TypeAAE Type = "aae"
+	// XML metadata / config / sidecar file.
+	TypeXML Type = "xml"
+	// YAML metadata / config / sidecar file.
+	TypeYaml Type = "yml"
+	// Text config / sidecar file.
+	TypeText Type = "txt"
+	// Markdown text sidecar file.
+	TypeMarkdown Type = "md"
+	// Unknown file format.
+	TypeOther Type = "unknown"
+)
+
+const (
+	// MimeTypeJpeg is jpeg image type
+	MimeTypeJpeg = "image/jpeg"
+)
+
+// Ext lists all the available and supported image file formats.
+var Ext = map[string]Type{
+	".crw":  TypeRaw,
+	".cr2":  TypeRaw,
+	".nef":  TypeRaw,
+	".arw":  TypeRaw,
+	".dng":  TypeRaw,
+	".mov":  TypeMovie,
+	".avi":  TypeMovie,
+	".yml":  TypeYaml,
+	".jpg":  TypeJpeg,
+	".thm":  TypeJpeg,
+	".jpeg": TypeJpeg,
+	".xmp":  TypeXMP,
+	".aae":  TypeAAE,
+	".heif": TypeHEIF,
+	".heic": TypeHEIF,
+	".3fr":  TypeRaw,
+	".ari":  TypeRaw,
+	".bay":  TypeRaw,
+	".cr3":  TypeRaw,
+	".cap":  TypeRaw,
+	".data": TypeRaw,
+	".dcs":  TypeRaw,
+	".dcr":  TypeRaw,
+	".drf":  TypeRaw,
+	".eip":  TypeRaw,
+	".erf":  TypeRaw,
+	".fff":  TypeRaw,
+	".gpr":  TypeRaw,
+	".iiq":  TypeRaw,
+	".k25":  TypeRaw,
+	".kdc":  TypeRaw,
+	".mdc":  TypeRaw,
+	".mef":  TypeRaw,
+	".mos":  TypeRaw,
+	".mrw":  TypeRaw,
+	".nrw":  TypeRaw,
+	".obm":  TypeRaw,
+	".orf":  TypeRaw,
+	".pef":  TypeRaw,
+	".ptx":  TypeRaw,
+	".pxn":  TypeRaw,
+	".r3d":  TypeRaw,
+	".raf":  TypeRaw,
+	".raw":  TypeRaw,
+	".rwl":  TypeRaw,
+	".rw2":  TypeRaw,
+	".rwz":  TypeRaw,
+	".sr2":  TypeRaw,
+	".srf":  TypeRaw,
+	".srw":  TypeRaw,
+	".tif":  TypeRaw,
+	".x3f":  TypeRaw,
+}
diff --git a/internal/util/zip.go b/internal/file/zip.go
similarity index 60%
rename from internal/util/zip.go
rename to internal/file/zip.go
index a998827c7..7957058c5 100644
--- a/internal/util/zip.go
+++ b/internal/file/zip.go
@@ -1,15 +1,16 @@
-package util
+package file
 
 import (
 	"archive/zip"
 	"io"
 	"os"
+	"strings"
 )
 
 // ZipFiles compresses one or many files into a single zip archive file.
 // Param 1: filename is the output zip file's name.
 // Param 2: files is a list of files to add to the zip.
-func ZipFiles(filename string, files []string) error {
+func Zip(filename string, files []string) error {
 	newZipFile, err := os.Create(filename)
 	if err != nil {
 		return err
@@ -21,7 +22,7 @@ func ZipFiles(filename string, files []string) error {
 
 	// Add files to zip
 	for _, file := range files {
-		if err = AddFileToZip(zipWriter, file); err != nil {
+		if err = AddToZip(zipWriter, file); err != nil {
 			return err
 		}
 	}
@@ -29,7 +30,7 @@ func ZipFiles(filename string, files []string) error {
 	return nil
 }
 
-func AddFileToZip(zipWriter *zip.Writer, filename string) error {
+func AddToZip(zipWriter *zip.Writer, filename string) error {
 
 	fileToZip, err := os.Open(filename)
 	if err != nil {
@@ -59,3 +60,29 @@ func AddFileToZip(zipWriter *zip.Writer, filename string) error {
 	_, err = io.Copy(writer, fileToZip)
 	return err
 }
+
+// Extract Zip file in destination directory
+func Unzip(src, dest string) (fileNames []string, err error) {
+	r, err := zip.OpenReader(src)
+	if err != nil {
+		return fileNames, err
+	}
+
+	defer r.Close()
+
+	for _, f := range r.File {
+		// Skip directories like __OSX
+		if strings.HasPrefix(f.Name, "__") {
+			continue
+		}
+
+		fn, err := copyToFile(f, dest)
+		if err != nil {
+			return fileNames, err
+		}
+
+		fileNames = append(fileNames, fn)
+	}
+
+	return fileNames, nil
+}
diff --git a/internal/nsfw/detector.go b/internal/nsfw/detector.go
index 2ded275c3..5440312c9 100644
--- a/internal/nsfw/detector.go
+++ b/internal/nsfw/detector.go
@@ -9,7 +9,7 @@ import (
 	"path/filepath"
 	"sync"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	tf "github.com/tensorflow/tensorflow/tensorflow/go"
 	"github.com/tensorflow/tensorflow/tensorflow/go/op"
 )
@@ -30,7 +30,7 @@ func NewDetector(modelPath string) *Detector {
 
 // LabelsFromFile returns matching labels for a jpeg media file.
 func (t *Detector) LabelsFromFile(filename string) (result Labels, err error) {
-	if util.MimeType(filename) != "image/jpeg" {
+	if file.MimeType(filename) != "image/jpeg" {
 		return result, fmt.Errorf("nsfw: \"%s\" is not a jpeg file", filename)
 	}
 
diff --git a/internal/photoprism/convert_test.go b/internal/photoprism/convert_test.go
index 2a6070994..f429b3280 100644
--- a/internal/photoprism/convert_test.go
+++ b/internal/photoprism/convert_test.go
@@ -5,7 +5,7 @@ import (
 	"testing"
 
 	"github.com/photoprism/photoprism/internal/config"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -30,7 +30,7 @@ func TestConvert_ToJpeg(t *testing.T) {
 
 	jpegFilename := conf.ImportPath() + "/fern_green.jpg"
 
-	assert.Truef(t, util.Exists(jpegFilename), "file does not exist: %s", jpegFilename)
+	assert.Truef(t, file.Exists(jpegFilename), "file does not exist: %s", jpegFilename)
 
 	t.Logf("Testing RAW to JPEG convert with %s", jpegFilename)
 
@@ -66,7 +66,7 @@ func TestConvert_ToJpeg(t *testing.T) {
 
 	imageRaw, _ := convert.ToJpeg(rawMediaFile)
 
-	assert.True(t, util.Exists(conf.ImportPath()+"/raw/IMG_2567.jpg"), "Jpeg file was not found - is Darktable installed?")
+	assert.True(t, file.Exists(conf.ImportPath()+"/raw/IMG_2567.jpg"), "Jpeg file was not found - is Darktable installed?")
 
 	assert.NotEqual(t, rawFilename, imageRaw.filename)
 
@@ -92,7 +92,7 @@ func TestConvert_Path(t *testing.T) {
 
 	jpegFilename := conf.ImportPath() + "/raw/canon_eos_6d.jpg"
 
-	assert.True(t, util.Exists(jpegFilename), "Jpeg file was not found - is Darktable installed?")
+	assert.True(t, file.Exists(jpegFilename), "Jpeg file was not found - is Darktable installed?")
 
 	image, err := NewMediaFile(jpegFilename)
 
@@ -108,15 +108,15 @@ func TestConvert_Path(t *testing.T) {
 
 	existingJpegFilename := conf.ImportPath() + "/raw/IMG_2567.jpg"
 
-	oldHash := util.Hash(existingJpegFilename)
+	oldHash := file.Hash(existingJpegFilename)
 
 	os.Remove(existingJpegFilename)
 
 	convert.Path(conf.ImportPath())
 
-	newHash := util.Hash(existingJpegFilename)
+	newHash := file.Hash(existingJpegFilename)
 
-	assert.True(t, util.Exists(existingJpegFilename), "Jpeg file was not found - is Darktable installed?")
+	assert.True(t, file.Exists(existingJpegFilename), "Jpeg file was not found - is Darktable installed?")
 
 	assert.NotEqual(t, oldHash, newHash, "Fingerprint of old and new JPEG file must not be the same")
 }
diff --git a/internal/photoprism/import.go b/internal/photoprism/import.go
index 52fdaf6e8..7ee467d12 100644
--- a/internal/photoprism/import.go
+++ b/internal/photoprism/import.go
@@ -12,8 +12,7 @@ import (
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/entity"
 	"github.com/photoprism/photoprism/internal/event"
-
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 )
 
 // Import represents an importer that can copy/move MediaFiles to the originals directory.
@@ -164,7 +163,7 @@ func (imp *Import) Start(importPath string) {
 	if imp.removeEmptyDirectories {
 		// Remove empty directories from import path
 		for _, directory := range directories {
-			if util.DirectoryIsEmpty(directory) {
+			if file.IsEmpty(directory) {
 				if err := os.Remove(directory); err != nil {
 					log.Errorf("import: could not deleted empty directory \"%s\" (%s)", directory, err)
 				} else {
@@ -202,8 +201,8 @@ func (imp *Import) DestinationFilename(mainFile *MediaFile, mediaFile *MediaFile
 
 	result := pathName + string(os.PathSeparator) + fileName + fileExtension
 
-	for util.Exists(result) {
-		if mediaFile.Hash() == util.Hash(result) {
+	for file.Exists(result) {
+		if mediaFile.Hash() == file.Hash(result) {
 			return result, fmt.Errorf("file already exists: %s", result)
 		}
 
diff --git a/internal/photoprism/mediafile.go b/internal/photoprism/mediafile.go
index 662a68c53..d5de4abf1 100644
--- a/internal/photoprism/mediafile.go
+++ b/internal/photoprism/mediafile.go
@@ -13,7 +13,7 @@ import (
 
 	"github.com/djherbis/times"
 	"github.com/photoprism/photoprism/internal/entity"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 )
 
 // MediaFile represents a single photo, video or sidecar file.
@@ -22,7 +22,7 @@ type MediaFile struct {
 	dateCreated    time.Time
 	timeZone       string
 	hash           string
-	fileType       FileType
+	fileType       file.Type
 	mimeType       string
 	perceptualHash string
 	width          int
@@ -33,13 +33,13 @@ type MediaFile struct {
 
 // NewMediaFile returns a new MediaFile.
 func NewMediaFile(filename string) (*MediaFile, error) {
-	if !util.Exists(filename) {
+	if !file.Exists(filename) {
 		return nil, fmt.Errorf("file does not exist: %s", filename)
 	}
 
 	instance := &MediaFile{
 		filename: filename,
-		fileType: FileTypeOther,
+		fileType: file.TypeOther,
 	}
 
 	return instance, nil
@@ -231,7 +231,7 @@ func (m *MediaFile) CanonicalNameFromFileWithDirectory() string {
 // Hash return a sha1 hash of a MediaFile based on the filename.
 func (m *MediaFile) Hash() string {
 	if len(m.hash) == 0 {
-		m.hash = util.Hash(m.Filename())
+		m.hash = file.Hash(m.Filename())
 	}
 
 	return m.hash
@@ -242,7 +242,7 @@ func (m *MediaFile) EditedFilename() string {
 	basename := filepath.Base(m.filename)
 
 	if strings.ToUpper(basename[:4]) == "IMG_" && strings.ToUpper(basename[:5]) != "IMG_E" {
-		if filename := filepath.Dir(m.filename) + string(os.PathSeparator) + basename[:4] + "E" + basename[4:]; util.Exists(filename) {
+		if filename := filepath.Dir(m.filename) + string(os.PathSeparator) + basename[:4] + "E" + basename[4:]; file.Exists(filename) {
 			return filename
 		}
 	}
@@ -381,7 +381,7 @@ func (m *MediaFile) MimeType() string {
 		return m.mimeType
 	}
 
-	m.mimeType = util.MimeType(m.Filename())
+	m.mimeType = file.MimeType(m.Filename())
 
 	return m.mimeType
 }
@@ -397,7 +397,7 @@ func (m *MediaFile) openFile() (*os.File, error) {
 
 // Exists checks if a media file exists by filename.
 func (m *MediaFile) Exists() bool {
-	return util.Exists(m.Filename())
+	return file.Exists(m.Filename())
 }
 
 // Remove a media file.
@@ -480,13 +480,13 @@ func (m *MediaFile) IsJpeg() bool {
 }
 
 // Type returns the type of the media file.
-func (m *MediaFile) Type() FileType {
-	return FileExtensions[m.Extension()]
+func (m *MediaFile) Type() file.Type {
+	return file.Ext[m.Extension()]
 }
 
 // HasType returns true if this media file is of a given type.
-func (m *MediaFile) HasType(t FileType) bool {
-	if t == FileTypeJpeg {
+func (m *MediaFile) HasType(t file.Type) bool {
+	if t == file.TypeJpeg {
 		return m.IsJpeg()
 	}
 
@@ -495,28 +495,28 @@ func (m *MediaFile) HasType(t FileType) bool {
 
 // IsRaw returns true if this media file a RAW file.
 func (m *MediaFile) IsRaw() bool {
-	return m.HasType(FileTypeRaw)
+	return m.HasType(file.TypeRaw)
 }
 
 // IsHEIF returns true if this media file is a High Efficiency Image File Format file.
 func (m *MediaFile) IsHEIF() bool {
-	return m.HasType(FileTypeHEIF)
+	return m.HasType(file.TypeHEIF)
 }
 
 // IsSidecar returns true if this media file is a sidecar file (containing metadata).
 func (m *MediaFile) IsSidecar() bool {
 	switch m.Type() {
-	case FileTypeXMP:
+	case file.TypeXMP:
 		return true
-	case FileTypeAAE:
+	case file.TypeAAE:
 		return true
-	case FileTypeXML:
+	case file.TypeXML:
 		return true
-	case FileTypeYaml:
+	case file.TypeYaml:
 		return true
-	case FileTypeText:
+	case file.TypeText:
 		return true
-	case FileTypeMarkdown:
+	case file.TypeMarkdown:
 		return true
 	default:
 		return false
@@ -526,7 +526,7 @@ func (m *MediaFile) IsSidecar() bool {
 // IsVideo returns true if this media file is a video file.
 func (m *MediaFile) IsVideo() bool {
 	switch m.Type() {
-	case FileTypeMovie:
+	case file.TypeMovie:
 		return true
 	}
 
@@ -544,9 +544,9 @@ func (m *MediaFile) Jpeg() (*MediaFile, error) {
 		return m, nil
 	}
 
-	jpegFilename := fmt.Sprintf("%s.%s", m.DirectoryBasename(), FileTypeJpeg)
+	jpegFilename := fmt.Sprintf("%s.%s", m.DirectoryBasename(), file.TypeJpeg)
 
-	if !util.Exists(jpegFilename) {
+	if !file.Exists(jpegFilename) {
 		return nil, fmt.Errorf("jpeg file does not exist: %s", jpegFilename)
 	}
 
diff --git a/internal/photoprism/mediafile_test.go b/internal/photoprism/mediafile_test.go
index 2a92144dd..25879c5dd 100644
--- a/internal/photoprism/mediafile_test.go
+++ b/internal/photoprism/mediafile_test.go
@@ -4,7 +4,7 @@ import (
 	"os"
 	"testing"
 
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/stretchr/testify/assert"
@@ -514,7 +514,7 @@ func TestMediaFile_Move(t *testing.T) {
 	f, err := NewMediaFile(conf.ExamplesPath() + "/table_white.jpg")
 	assert.Nil(t, err)
 	f.Copy(origName)
-	assert.True(t, util.Exists(origName))
+	assert.True(t, file.Exists(origName))
 
 	m, err := NewMediaFile(origName)
 	assert.Nil(t, err)
@@ -523,7 +523,7 @@ func TestMediaFile_Move(t *testing.T) {
 		t.Errorf("failed to move: %s", err)
 	}
 
-	assert.True(t, util.Exists(destName))
+	assert.True(t, file.Exists(destName))
 	assert.Equal(t, destName, m.Filename())
 }
 
@@ -539,7 +539,7 @@ func TestMediaFile_Copy(t *testing.T) {
 	mediaFile, err := NewMediaFile(conf.ExamplesPath() + "/table_white.jpg")
 	assert.Nil(t, err)
 	mediaFile.Copy(tmpPath + "table_whitecopy.jpg")
-	assert.True(t, util.Exists(tmpPath+"table_whitecopy.jpg"))
+	assert.True(t, file.Exists(tmpPath+"table_whitecopy.jpg"))
 }
 
 func TestMediaFile_Extension(t *testing.T) {
diff --git a/internal/photoprism/tensorflow.go b/internal/photoprism/tensorflow.go
index 6b7cc7822..1c136befe 100644
--- a/internal/photoprism/tensorflow.go
+++ b/internal/photoprism/tensorflow.go
@@ -16,7 +16,7 @@ import (
 
 	"github.com/disintegration/imaging"
 	"github.com/photoprism/photoprism/internal/config"
-	"github.com/photoprism/photoprism/internal/util"
+	"github.com/photoprism/photoprism/internal/file"
 	tf "github.com/tensorflow/tensorflow/tensorflow/go"
 	"gopkg.in/yaml.v2"
 )
@@ -69,7 +69,7 @@ func (t *TensorFlow) loadLabelRules() (err error) {
 
 	log.Debugf("tensorflow: loading label rules from \"%s\"", filepath.Base(fileName))
 
-	if !util.Exists(fileName) {
+	if !file.Exists(fileName) {
 		e := fmt.Errorf("tensorflow: label rules file not found in \"%s\"", filepath.Base(fileName))
 		log.Error(e.Error())
 		return e
diff --git a/internal/photoprism/thumbnails.go b/internal/photoprism/thumbnails.go
index be5bbe042..88d9d5fc3 100644
--- a/internal/photoprism/thumbnails.go
+++ b/internal/photoprism/thumbnails.go
@@ -3,85 +3,19 @@ package photoprism
 import (
 	"fmt"
 	"image"
-	"image/png"
 	"os"
-	"path"
 	"path/filepath"
 	"strings"
 	"time"
 
-	"github.com/photoprism/photoprism/internal/config"
 	"github.com/photoprism/photoprism/internal/event"
+	"github.com/photoprism/photoprism/internal/file"
+	"github.com/photoprism/photoprism/internal/thumb"
 
 	"github.com/disintegration/imaging"
 	"github.com/photoprism/photoprism/internal/util"
 )
 
-var (
-	MaxThumbWidth    = 8192
-	MaxThumbHeight   = 8192
-	JpegQuality      = 95
-	JpegQualitySmall = 80
-)
-
-const (
-	ResampleFillCenter ResampleOption = iota
-	ResampleFillTopLeft
-	ResampleFillBottomRight
-	ResampleFit
-	ResampleResize
-	ResampleNearestNeighbor
-	ResampleLanczos
-	ResamplePng
-)
-
-type ResampleOption int
-
-var ResampleMethods = map[ResampleOption]string{
-	ResampleFillCenter:      "center",
-	ResampleFillTopLeft:     "left",
-	ResampleFillBottomRight: "right",
-	ResampleFit:             "fit",
-	ResampleResize:          "resize",
-}
-
-type ThumbnailType struct {
-	Source  string
-	Width   int
-	Height  int
-	Public  bool
-	Options []ResampleOption
-}
-
-var ThumbnailTypes = map[string]ThumbnailType{
-	"tile_50":   {"tile_500", 50, 50, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
-	"tile_100":  {"tile_500", 100, 100, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
-	"tile_224":  {"tile_500", 224, 224, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
-	"tile_500":  {"", 500, 500, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
-	"colors":    {"fit_720", 3, 3, false, []ResampleOption{ResampleResize, ResampleNearestNeighbor, ResamplePng}},
-	"left_224":  {"fit_720", 224, 224, false, []ResampleOption{ResampleFillTopLeft, ResampleLanczos}},
-	"right_224": {"fit_720", 224, 224, false, []ResampleOption{ResampleFillBottomRight, ResampleLanczos}},
-	"fit_720":   {"", 720, 720, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-	"fit_1280":  {"fit_2048", 1280, 1024, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-	"fit_1920":  {"fit_2048", 1920, 1200, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-	"fit_2048":  {"", 2048, 2048, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-	"fit_2560":  {"", 2560, 1600, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-	"fit_3840":  {"", 3840, 2400, true, []ResampleOption{ResampleFit, ResampleLanczos}},
-}
-
-var DefaultThumbnails = []string{
-	"fit_3840", "fit_2560", "fit_2048", "fit_1920", "fit_1280", "fit_720", "right_224", "left_224", "colors", "tile_500", "tile_224", "tile_100", "tile_50",
-}
-
-func init() {
-	for name, t := range ThumbnailTypes {
-		if t.Public {
-			thumb := config.Thumbnail{Name: name, Width: t.Width, Height: t.Height}
-			config.Thumbnails = append(config.Thumbnails, thumb)
-		}
-	}
-}
-
 // CreateThumbnailsFromOriginals creates default thumbnails for all originals.
 func CreateThumbnailsFromOriginals(originalsPath string, thumbnailsPath string, force bool) error {
 	err := filepath.Walk(originalsPath, func(filename string, fileInfo os.FileInfo, err error) error {
@@ -120,14 +54,14 @@ func CreateThumbnailsFromOriginals(originalsPath string, thumbnailsPath string,
 
 // Thumbnail returns a thumbnail filename.
 func (m *MediaFile) Thumbnail(path string, typeName string) (filename string, err error) {
-	thumbType, ok := ThumbnailTypes[typeName]
+	thumbType, ok := thumb.Types[typeName]
 
 	if !ok {
 		log.Errorf("invalid type: %s", typeName)
 		return "", fmt.Errorf("invalid type: %s", typeName)
 	}
 
-	thumbnail, err := ThumbnailFromFile(m.Filename(), m.Hash(), path, thumbType.Width, thumbType.Height, thumbType.Options...)
+	thumbnail, err := thumb.FromFile(m.Filename(), m.Hash(), path, thumbType.Width, thumbType.Height, thumbType.Options...)
 
 	if err != nil {
 		log.Errorf("could not create thumbnail: %s", err)
@@ -148,157 +82,6 @@ func (m *MediaFile) Resample(path string, typeName string) (img image.Image, err
 	return imaging.Open(filename, imaging.AutoOrientation(true))
 }
 
-func ResampleOptions(opts ...ResampleOption) (method ResampleOption, filter imaging.ResampleFilter, format FileType) {
-	method = ResampleFit
-	filter = imaging.Lanczos
-	format = FileTypeJpeg
-
-	for _, option := range opts {
-		switch option {
-		case ResamplePng:
-			format = FileTypePng
-		case ResampleNearestNeighbor:
-			filter = imaging.NearestNeighbor
-		case ResampleLanczos:
-			filter = imaging.Lanczos
-		case ResampleFillTopLeft:
-			method = ResampleFillTopLeft
-		case ResampleFillCenter:
-			method = ResampleFillCenter
-		case ResampleFillBottomRight:
-			method = ResampleFillBottomRight
-		case ResampleFit:
-			method = ResampleFit
-		case ResampleResize:
-			method = ResampleResize
-		default:
-			panic(fmt.Errorf("not a valid resample option: %d", option))
-		}
-	}
-
-	return method, filter, format
-}
-
-func Resample(img image.Image, width, height int, opts ...ResampleOption) (result image.Image) {
-	method, filter, _ := ResampleOptions(opts...)
-
-	if method == ResampleFit {
-		result = imaging.Fit(img, width, height, filter)
-	} else if method == ResampleFillCenter {
-		result = imaging.Fill(img, width, height, imaging.Center, filter)
-	} else if method == ResampleFillTopLeft {
-		result = imaging.Fill(img, width, height, imaging.TopLeft, filter)
-	} else if method == ResampleFillBottomRight {
-		result = imaging.Fill(img, width, height, imaging.BottomRight, filter)
-	} else if method == ResampleResize {
-		result = imaging.Resize(img, width, height, filter)
-	}
-
-	return result
-}
-
-func ThumbnailPostfix(width, height int, opts ...ResampleOption) (result string) {
-	method, _, format := ResampleOptions(opts...)
-
-	result = fmt.Sprintf("%dx%d_%s.%s", width, height, ResampleMethods[method], format)
-
-	return result
-}
-
-func ThumbnailFilename(hash string, thumbPath string, width, height int, opts ...ResampleOption) (filename string, err error) {
-	if width < 0 || width > MaxThumbWidth {
-		return "", fmt.Errorf("width has an invalid value: %d", width)
-	}
-
-	if height < 0 || height > MaxThumbHeight {
-		return "", fmt.Errorf("height has an invalid value: %d", height)
-	}
-
-	if len(hash) < 4 {
-		return "", fmt.Errorf("file hash is empty or too short: %s", hash)
-	}
-
-	if len(thumbPath) == 0 {
-		return "", fmt.Errorf("thumbnail path is empty: %s", thumbPath)
-	}
-
-	postfix := ThumbnailPostfix(width, height, opts...)
-	p := path.Join(thumbPath, hash[0:1], hash[1:2], hash[2:3])
-
-	if err := os.MkdirAll(p, os.ModePerm); err != nil {
-		return "", err
-	}
-
-	filename = fmt.Sprintf("%s/%s_%s", p, hash, postfix)
-
-	return filename, nil
-}
-
-func ThumbnailFromFile(imageFilename string, hash string, thumbPath string, width, height int, opts ...ResampleOption) (fileName string, err error) {
-	if len(hash) < 4 {
-		return "", fmt.Errorf("file hash is empty or too short: %s", hash)
-	}
-
-	if len(imageFilename) < 4 {
-		return "", fmt.Errorf("image filename is empty or too short: %s", imageFilename)
-	}
-
-	fileName, err = ThumbnailFilename(hash, thumbPath, width, height, opts...)
-
-	if err != nil {
-		log.Errorf("can't determine thumb filename: %s", err)
-		return "", err
-	}
-
-	if util.Exists(fileName) {
-		return fileName, nil
-	}
-
-	img, err := imaging.Open(imageFilename, imaging.AutoOrientation(true))
-
-	if err != nil {
-		log.Errorf("can't open original: %s", err)
-		return "", err
-	}
-
-	if _, err := CreateThumbnail(img, fileName, width, height, opts...); err != nil {
-		return "", err
-	}
-
-	return fileName, nil
-}
-
-func CreateThumbnail(img image.Image, fileName string, width, height int, opts ...ResampleOption) (result image.Image, err error) {
-	if width < 0 || width > MaxThumbWidth {
-		return img, fmt.Errorf("width has an invalid value: %d", width)
-	}
-
-	if height < 0 || height > MaxThumbHeight {
-		return img, fmt.Errorf("height has an invalid value: %d", height)
-	}
-
-	result = Resample(img, width, height, opts...)
-
-	var saveOption imaging.EncodeOption
-
-	if filepath.Ext(fileName) == "."+string(FileTypePng) {
-		saveOption = imaging.PNGCompressionLevel(png.DefaultCompression)
-	} else if width <= 150 && height <= 150 {
-		saveOption = imaging.JPEGQuality(JpegQualitySmall)
-	} else {
-		saveOption = imaging.JPEGQuality(JpegQuality)
-	}
-
-	err = imaging.Save(result, fileName, saveOption)
-
-	if err != nil {
-		log.Errorf("failed to save thumbnail: %v", err)
-		return result, err
-	}
-
-	return result, nil
-}
-
 func (m *MediaFile) CreateDefaultThumbnails(thumbPath string, force bool) (err error) {
 	defer util.ProfileTime(time.Now(), fmt.Sprintf("creating thumbnails for \"%s\"", m.Filename()))
 
@@ -314,31 +97,31 @@ func (m *MediaFile) CreateDefaultThumbnails(thumbPath string, force bool) (err e
 	var sourceImg image.Image
 	var sourceImgType string
 
-	for _, name := range DefaultThumbnails {
-		thumbType := ThumbnailTypes[name]
+	for _, name := range thumb.DefaultTypes {
+		thumbType := thumb.Types[name]
 
-		if thumbType.Height > MaxThumbHeight || thumbType.Width > MaxThumbWidth {
+		if thumbType.Height > thumb.MaxHeight || thumbType.Width > thumb.MaxWidth {
 			log.Debugf("thumbs: size exceeds limit (width %d, height %d)", thumbType.Width, thumbType.Height)
 			continue
 		}
 
-		if fileName, err := ThumbnailFilename(hash, thumbPath, thumbType.Width, thumbType.Height, thumbType.Options...); err != nil {
+		if fileName, err := thumb.Filename(hash, thumbPath, thumbType.Width, thumbType.Height, thumbType.Options...); err != nil {
 			log.Errorf("could not create %s thumbnail: \"%s\"", name, err)
 
 			return err
 		} else {
-			if !force && util.Exists(fileName) {
+			if !force && file.Exists(fileName) {
 				continue
 			}
 
 			if thumbType.Source != "" {
 				if thumbType.Source == sourceImgType && sourceImg != nil {
-					_, err = CreateThumbnail(sourceImg, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
+					_, err = thumb.Create(sourceImg, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
 				} else {
-					_, err = CreateThumbnail(img, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
+					_, err = thumb.Create(img, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
 				}
 			} else {
-				sourceImg, err = CreateThumbnail(img, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
+				sourceImg, err = thumb.Create(img, fileName, thumbType.Width, thumbType.Height, thumbType.Options...)
 				sourceImgType = name
 			}
 
diff --git a/internal/photoprism/thumbnails_test.go b/internal/photoprism/thumbnails_test.go
index 93423c01d..efc14adcb 100644
--- a/internal/photoprism/thumbnails_test.go
+++ b/internal/photoprism/thumbnails_test.go
@@ -7,6 +7,7 @@ import (
 	"github.com/disintegration/imaging"
 	"github.com/photoprism/photoprism/internal/entity"
 	"github.com/photoprism/photoprism/internal/nsfw"
+	"github.com/photoprism/photoprism/internal/thumb"
 
 	"github.com/photoprism/photoprism/internal/config"
 	"github.com/stretchr/testify/assert"
@@ -117,7 +118,7 @@ func TestThumbnails_Resample(t *testing.T) {
 
 }
 
-func TestThumbnails_ThumbnailFilename(t *testing.T) {
+func TestThumbnails_Filename(t *testing.T) {
 	conf := config.TestConfig()
 
 	thumbsPath := conf.CachePath() + "/_tmp"
@@ -129,25 +130,25 @@ func TestThumbnails_ThumbnailFilename(t *testing.T) {
 	}
 
 	t.Run("", func(t *testing.T) {
-		filename, err := ThumbnailFilename("99988", thumbsPath, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		filename, err := thumb.Filename("99988", thumbsPath, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 		assert.Nil(t, err)
 		assert.Equal(t, "/go/src/github.com/photoprism/photoprism/assets/testdata/cache/_tmp/9/9/9/99988_150x150_fit.jpg", filename)
 	})
 	t.Run("hash too short", func(t *testing.T) {
-		_, err := ThumbnailFilename("999", thumbsPath, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		_, err := thumb.Filename("999", thumbsPath, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 		assert.Equal(t, "file hash is empty or too short: 999", err.Error())
 	})
 	t.Run("invalid width", func(t *testing.T) {
-		_, err := ThumbnailFilename("99988", thumbsPath, -4, 150, ResampleFit, ResampleNearestNeighbor)
+		_, err := thumb.Filename("99988", thumbsPath, -4, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 		assert.Equal(t, "width has an invalid value: -4", err.Error())
 	})
 	t.Run("invalid height", func(t *testing.T) {
-		_, err := ThumbnailFilename("99988", thumbsPath, 200, -1, ResampleFit, ResampleNearestNeighbor)
+		_, err := thumb.Filename("99988", thumbsPath, 200, -1, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 		assert.Equal(t, "height has an invalid value: -1", err.Error())
 	})
 	t.Run("empty thumbpath", func(t *testing.T) {
 		path := ""
-		_, err := ThumbnailFilename("99988", path, 200, 150, ResampleFit, ResampleNearestNeighbor)
+		_, err := thumb.Filename("99988", path, 200, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 		assert.Equal(t, "thumbnail path is empty: ", err.Error())
 	})
 }
@@ -169,9 +170,9 @@ func TestThumbnails_ThumbnailFromFile(t *testing.T) {
 			FileHash: "1234568889",
 		}
 
-		thumb, err := ThumbnailFromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
+		thumbnail, err := thumb.FromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
 		assert.Nil(t, err)
-		assert.FileExists(t, thumb)
+		assert.FileExists(t, thumbnail)
 	})
 
 	t.Run("hash too short", func(t *testing.T) {
@@ -180,7 +181,7 @@ func TestThumbnails_ThumbnailFromFile(t *testing.T) {
 			FileHash: "123",
 		}
 
-		_, err := ThumbnailFromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
+		_, err := thumb.FromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
 		assert.Equal(t, "file hash is empty or too short: 123", err.Error())
 	})
 	t.Run("filename too short", func(t *testing.T) {
@@ -189,7 +190,7 @@ func TestThumbnails_ThumbnailFromFile(t *testing.T) {
 			FileHash: "12367890",
 		}
 
-		_, err := ThumbnailFromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
+		_, err := thumb.FromFile(fileModel.FileName, fileModel.FileHash, thumbsPath, 224, 224)
 		assert.Equal(t, "image filename is empty or too short: xxx", err.Error())
 	})
 }
@@ -210,7 +211,7 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 	}
 
 	t.Run("valid parameter", func(t *testing.T) {
-		expectedFilename, err := ThumbnailFilename("12345", thumbsPath, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		expectedFilename, err := thumb.Filename("12345", thumbsPath, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		if err != nil {
 			t.Error(err)
@@ -222,13 +223,13 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 			t.Errorf("can't open original: %s", err)
 		}
 
-		thumb, err := CreateThumbnail(img, expectedFilename, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		thumbnail, err := thumb.Create(img, expectedFilename, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		assert.Empty(t, err)
 
-		assert.NotNil(t, thumb)
+		assert.NotNil(t, thumbnail)
 
-		bounds := thumb.Bounds()
+		bounds := thumbnail.Bounds()
 
 		assert.Equal(t, 150, bounds.Dx())
 		assert.Equal(t, 99, bounds.Dy())
@@ -236,7 +237,7 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 		assert.FileExists(t, expectedFilename)
 	})
 	t.Run("invalid width", func(t *testing.T) {
-		expectedFilename, err := ThumbnailFilename("12345", thumbsPath, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		expectedFilename, err := thumb.Filename("12345", thumbsPath, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		if err != nil {
 			t.Error(err)
@@ -248,7 +249,7 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 			t.Errorf("can't open original: %s", err)
 		}
 
-		thumbnail, err := CreateThumbnail(img, expectedFilename, -1, 150, ResampleFit, ResampleNearestNeighbor)
+		thumbnail, err := thumb.Create(img, expectedFilename, -1, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		assert.Equal(t, "width has an invalid value: -1", err.Error())
 		bounds := thumbnail.Bounds()
@@ -256,7 +257,7 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 	})
 
 	t.Run("invalid height", func(t *testing.T) {
-		expectedFilename, err := ThumbnailFilename("12345", thumbsPath, 150, 150, ResampleFit, ResampleNearestNeighbor)
+		expectedFilename, err := thumb.Filename("12345", thumbsPath, 150, 150, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		if err != nil {
 			t.Error(err)
@@ -268,7 +269,7 @@ func TestThumbnails_CreateThumbnail(t *testing.T) {
 			t.Errorf("can't open original: %s", err)
 		}
 
-		thumbnail, err := CreateThumbnail(img, expectedFilename, 150, -1, ResampleFit, ResampleNearestNeighbor)
+		thumbnail, err := thumb.Create(img, expectedFilename, 150, -1, thumb.ResampleFit, thumb.ResampleNearestNeighbor)
 
 		assert.Equal(t, "height has an invalid value: -1", err.Error())
 		bounds := thumbnail.Bounds()
@@ -294,7 +295,7 @@ func TestThumbnails_CreateDefaultThumbnails(t *testing.T) {
 
 	assert.Empty(t, err)
 
-	thumbFilename, err := ThumbnailFilename(m.Hash(), thumbsPath, ThumbnailTypes["tile_50"].Width, ThumbnailTypes["tile_50"].Height, ThumbnailTypes["tile_50"].Options...)
+	thumbFilename, err := thumb.Filename(m.Hash(), thumbsPath, thumb.Types["tile_50"].Width, thumb.Types["tile_50"].Height, thumb.Types["tile_50"].Options...)
 
 	assert.Empty(t, err)
 
diff --git a/internal/rnd/rnd.go b/internal/rnd/rnd.go
new file mode 100644
index 000000000..236e9a128
--- /dev/null
+++ b/internal/rnd/rnd.go
@@ -0,0 +1,14 @@
+/*
+Package config contains random token functions.
+
+Additional information can be found in our Developer Guide:
+
+https://github.com/photoprism/photoprism/wiki
+*/
+package rnd
+
+import (
+	"github.com/photoprism/photoprism/internal/event"
+)
+
+var log = event.Log
diff --git a/internal/util/token.go b/internal/rnd/token.go
similarity index 83%
rename from internal/util/token.go
rename to internal/rnd/token.go
index a5b88a3f4..eb53f7db6 100644
--- a/internal/util/token.go
+++ b/internal/rnd/token.go
@@ -1,4 +1,4 @@
-package util
+package rnd
 
 import (
 	"crypto/rand"
@@ -9,7 +9,7 @@ import (
 	uuid "github.com/satori/go.uuid"
 )
 
-func RandomToken(size uint) string {
+func Token(size uint) string {
 	if size > 10 || size < 1 {
 		log.Fatalf("size out of range: %d", size)
 	}
@@ -32,14 +32,14 @@ func RandomToken(size uint) string {
 	return string(result[:size])
 }
 
-func RandomPassword() string {
-	return RandomToken(8)
+func Password() string {
+	return Token(8)
 }
 
 func ID() string {
 	result := make([]byte, 0, 16)
 	result = append(result, strconv.FormatInt(time.Now().UTC().Unix(), 36)[0:6]...)
-	result = append(result, RandomToken(10)...)
+	result = append(result, Token(10)...)
 
 	return string(result)
 }
diff --git a/internal/util/token_test.go b/internal/rnd/token_test.go
similarity index 84%
rename from internal/util/token_test.go
rename to internal/rnd/token_test.go
index 7e75e65b0..870561bde 100644
--- a/internal/util/token_test.go
+++ b/internal/rnd/token_test.go
@@ -1,4 +1,4 @@
-package util
+package rnd
 
 import (
 	"testing"
@@ -8,24 +8,24 @@ import (
 
 func TestRandomToken(t *testing.T) {
 	t.Run("size 4", func(t *testing.T) {
-		token := RandomToken(4)
+		token := Token(4)
 		assert.NotEmpty(t, token)
 	})
 	t.Run("size 8", func(t *testing.T) {
-		token := RandomToken(9)
+		token := Token(9)
 		assert.NotEmpty(t, token)
 	})
 }
 
 func TestRandomPassword(t *testing.T) {
-	pw := RandomPassword()
+	pw := Password()
 	t.Logf("password: %s", pw)
 	assert.Equal(t, 8, len(pw))
 }
 
 func BenchmarkRandomPassword(b *testing.B) {
 	for n := 0; n < b.N; n++ {
-		RandomPassword()
+		Password()
 	}
 }
 
@@ -45,12 +45,12 @@ func BenchmarkUUID(b *testing.B) {
 
 func BenchmarkRandomToken4(b *testing.B) {
 	for n := 0; n < b.N; n++ {
-		RandomToken(4)
+		Token(4)
 	}
 }
 
 func BenchmarkRandomToken3(b *testing.B) {
 	for n := 0; n < b.N; n++ {
-		RandomToken(3)
+		Token(3)
 	}
 }
diff --git a/internal/thumb/create.go b/internal/thumb/create.go
new file mode 100644
index 000000000..5b0462ebf
--- /dev/null
+++ b/internal/thumb/create.go
@@ -0,0 +1,165 @@
+package thumb
+
+import (
+	"fmt"
+	"image"
+	"image/png"
+	"os"
+	"path"
+	"path/filepath"
+
+	"github.com/photoprism/photoprism/internal/file"
+
+	"github.com/disintegration/imaging"
+)
+
+func ResampleOptions(opts ...ResampleOption) (method ResampleOption, filter imaging.ResampleFilter, format file.Type) {
+	method = ResampleFit
+	filter = imaging.Lanczos
+	format = file.TypeJpeg
+
+	for _, option := range opts {
+		switch option {
+		case ResamplePng:
+			format = file.TypePng
+		case ResampleNearestNeighbor:
+			filter = imaging.NearestNeighbor
+		case ResampleLanczos:
+			filter = imaging.Lanczos
+		case ResampleFillTopLeft:
+			method = ResampleFillTopLeft
+		case ResampleFillCenter:
+			method = ResampleFillCenter
+		case ResampleFillBottomRight:
+			method = ResampleFillBottomRight
+		case ResampleFit:
+			method = ResampleFit
+		case ResampleResize:
+			method = ResampleResize
+		default:
+			panic(fmt.Errorf("not a valid resample option: %d", option))
+		}
+	}
+
+	return method, filter, format
+}
+
+func Resample(img image.Image, width, height int, opts ...ResampleOption) (result image.Image) {
+	method, filter, _ := ResampleOptions(opts...)
+
+	if method == ResampleFit {
+		result = imaging.Fit(img, width, height, filter)
+	} else if method == ResampleFillCenter {
+		result = imaging.Fill(img, width, height, imaging.Center, filter)
+	} else if method == ResampleFillTopLeft {
+		result = imaging.Fill(img, width, height, imaging.TopLeft, filter)
+	} else if method == ResampleFillBottomRight {
+		result = imaging.Fill(img, width, height, imaging.BottomRight, filter)
+	} else if method == ResampleResize {
+		result = imaging.Resize(img, width, height, filter)
+	}
+
+	return result
+}
+
+func Postfix(width, height int, opts ...ResampleOption) (result string) {
+	method, _, format := ResampleOptions(opts...)
+
+	result = fmt.Sprintf("%dx%d_%s.%s", width, height, ResampleMethods[method], format)
+
+	return result
+}
+
+func Filename(hash string, thumbPath string, width, height int, opts ...ResampleOption) (filename string, err error) {
+	if width < 0 || width > MaxWidth {
+		return "", fmt.Errorf("width has an invalid value: %d", width)
+	}
+
+	if height < 0 || height > MaxHeight {
+		return "", fmt.Errorf("height has an invalid value: %d", height)
+	}
+
+	if len(hash) < 4 {
+		return "", fmt.Errorf("file hash is empty or too short: %s", hash)
+	}
+
+	if len(thumbPath) == 0 {
+		return "", fmt.Errorf("thumbnail path is empty: %s", thumbPath)
+	}
+
+	postfix := Postfix(width, height, opts...)
+	p := path.Join(thumbPath, hash[0:1], hash[1:2], hash[2:3])
+
+	if err := os.MkdirAll(p, os.ModePerm); err != nil {
+		return "", err
+	}
+
+	filename = fmt.Sprintf("%s/%s_%s", p, hash, postfix)
+
+	return filename, nil
+}
+
+func FromFile(imageFilename string, hash string, thumbPath string, width, height int, opts ...ResampleOption) (fileName string, err error) {
+	if len(hash) < 4 {
+		return "", fmt.Errorf("file hash is empty or too short: %s", hash)
+	}
+
+	if len(imageFilename) < 4 {
+		return "", fmt.Errorf("image filename is empty or too short: %s", imageFilename)
+	}
+
+	fileName, err = Filename(hash, thumbPath, width, height, opts...)
+
+	if err != nil {
+		log.Errorf("can't determine thumb filename: %s", err)
+		return "", err
+	}
+
+	if file.Exists(fileName) {
+		return fileName, nil
+	}
+
+	img, err := imaging.Open(imageFilename, imaging.AutoOrientation(true))
+
+	if err != nil {
+		log.Errorf("can't open original: %s", err)
+		return "", err
+	}
+
+	if _, err := Create(img, fileName, width, height, opts...); err != nil {
+		return "", err
+	}
+
+	return fileName, nil
+}
+
+func Create(img image.Image, fileName string, width, height int, opts ...ResampleOption) (result image.Image, err error) {
+	if width < 0 || width > MaxWidth {
+		return img, fmt.Errorf("width has an invalid value: %d", width)
+	}
+
+	if height < 0 || height > MaxHeight {
+		return img, fmt.Errorf("height has an invalid value: %d", height)
+	}
+
+	result = Resample(img, width, height, opts...)
+
+	var saveOption imaging.EncodeOption
+
+	if filepath.Ext(fileName) == "."+string(file.TypePng) {
+		saveOption = imaging.PNGCompressionLevel(png.DefaultCompression)
+	} else if width <= 150 && height <= 150 {
+		saveOption = imaging.JPEGQuality(JpegQualitySmall)
+	} else {
+		saveOption = imaging.JPEGQuality(JpegQuality)
+	}
+
+	err = imaging.Save(result, fileName, saveOption)
+
+	if err != nil {
+		log.Errorf("failed to save thumbnail: %v", err)
+		return result, err
+	}
+
+	return result, nil
+}
diff --git a/internal/thumb/thumb.go b/internal/thumb/thumb.go
new file mode 100644
index 000000000..4fa66bd74
--- /dev/null
+++ b/internal/thumb/thumb.go
@@ -0,0 +1,14 @@
+/*
+This package encapsulates JPEG thumbnail generation.
+
+Additional information can be found in our Developer Guide:
+
+https://github.com/photoprism/photoprism/wiki
+*/
+package thumb
+
+import (
+	"github.com/photoprism/photoprism/internal/event"
+)
+
+var log = event.Log
diff --git a/internal/thumb/types.go b/internal/thumb/types.go
new file mode 100644
index 000000000..015765a5f
--- /dev/null
+++ b/internal/thumb/types.go
@@ -0,0 +1,57 @@
+package thumb
+
+var (
+	MaxWidth         = 8192
+	MaxHeight        = 8192
+	JpegQuality      = 95
+	JpegQualitySmall = 80
+)
+
+const (
+	ResampleFillCenter ResampleOption = iota
+	ResampleFillTopLeft
+	ResampleFillBottomRight
+	ResampleFit
+	ResampleResize
+	ResampleNearestNeighbor
+	ResampleLanczos
+	ResamplePng
+)
+
+type ResampleOption int
+
+var ResampleMethods = map[ResampleOption]string{
+	ResampleFillCenter:      "center",
+	ResampleFillTopLeft:     "left",
+	ResampleFillBottomRight: "right",
+	ResampleFit:             "fit",
+	ResampleResize:          "resize",
+}
+
+type Type struct {
+	Source  string
+	Width   int
+	Height  int
+	Public  bool
+	Options []ResampleOption
+}
+
+var Types = map[string]Type{
+	"tile_50":   {"tile_500", 50, 50, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
+	"tile_100":  {"tile_500", 100, 100, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
+	"tile_224":  {"tile_500", 224, 224, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
+	"tile_500":  {"", 500, 500, false, []ResampleOption{ResampleFillCenter, ResampleLanczos}},
+	"colors":    {"fit_720", 3, 3, false, []ResampleOption{ResampleResize, ResampleNearestNeighbor, ResamplePng}},
+	"left_224":  {"fit_720", 224, 224, false, []ResampleOption{ResampleFillTopLeft, ResampleLanczos}},
+	"right_224": {"fit_720", 224, 224, false, []ResampleOption{ResampleFillBottomRight, ResampleLanczos}},
+	"fit_720":   {"", 720, 720, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+	"fit_1280":  {"fit_2048", 1280, 1024, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+	"fit_1920":  {"fit_2048", 1920, 1200, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+	"fit_2048":  {"", 2048, 2048, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+	"fit_2560":  {"", 2560, 1600, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+	"fit_3840":  {"", 3840, 2400, true, []ResampleOption{ResampleFit, ResampleLanczos}},
+}
+
+var DefaultTypes = []string{
+	"fit_3840", "fit_2560", "fit_2048", "fit_1920", "fit_1280", "fit_720", "right_224", "left_224", "colors", "tile_500", "tile_224", "tile_100", "tile_50",
+}