diff --git a/server/texture-sync-server/src/persistency/mod.rs b/server/texture-sync-server/src/persistency/mod.rs
index 90c37cc..764dc7b 100644
--- a/server/texture-sync-server/src/persistency/mod.rs
+++ b/server/texture-sync-server/src/persistency/mod.rs
@@ -133,6 +133,7 @@ impl DataStore {
         Ok(file_path.is_file())
     }
 
+    // Todo: this return type looks wrong : ImageError can't happen
     pub fn read_texture_file_by_hash(&mut self, hash: &Sha256) -> TextureFileResult {
         use std::fs::*;
         use std::io::*;
@@ -165,14 +166,12 @@ impl DataStore {
     }
 
     fn flush_metadata(&self) -> io::Result<()> {
-        use std::ops::Deref;
-
         let f = metadata_file::MetadataFile::from_iterator(self.textures.iter());
 
         f.store(self.index_file_path().as_path())
     }
 
-    pub fn get_texture_preview(&mut self, hash: &Sha256) -> TextureFileResult {
+    pub fn get_texture_preview(&mut self, hash: &Sha256, desired_format : TextureFormat) -> TextureFileResult {
         unimplemented!();
     }