diff --git a/src/library.rs b/src/library.rs
index afefd54..7d95493 100644
--- a/src/library.rs
+++ b/src/library.rs
@@ -18,7 +18,7 @@ use rocksdb::IteratorMode;
 use rocksdb::DB;
 
 // Used to ensure DB is invalidated after schema changes.
-const LIBRARY_GENERATION: &'static str = "5";
+const LIBRARY_GENERATION: &'static str = "11";
 
 #[derive(Clone)]
 pub struct Library {
@@ -36,7 +36,10 @@ impl Library {
             cache_db,
             root,
         };
-        lib.clean_db()?;
+        let cnt = lib.clean_db()?;
+        if cnt != 0 {
+            info!("Deleted {} entries", cnt);
+        }
         if !lib.originals_dir.exists() {
             info!(
                 "create originals dir {}",
@@ -47,27 +50,30 @@ impl Library {
         Ok(lib)
     }
     // Removes all data in the database from older schema.
-    pub fn clean_db(&self) -> Result<(), rocksdb::Error> {
+    pub fn clean_db(&self) -> Result<usize, rocksdb::Error> {
         Library::gc(LIBRARY_GENERATION, &self.cache_db)
     }
-    fn gc(generation: &str, db: &DB) -> Result<(), rocksdb::Error> {
+    fn gc(generation: &str, db: &DB) -> Result<usize, rocksdb::Error> {
         let gen = format!("{}/", generation);
         // '0' is the next character after '/', so iterator's starting there would be after the
         // last `gen` entry.
         let next_gen = format!("{}0", generation);
+        let mut del_cnt = 0;
         for (k, _v) in db.iterator(IteratorMode::From(gen.as_bytes(), Direction::Reverse)) {
             if !k.starts_with(gen.as_bytes()) {
                 info!("deleting stale key: {}", String::from_utf8_lossy(&k));
                 db.delete(k)?;
+                del_cnt += 1;
             }
         }
         for (k, _v) in db.iterator(IteratorMode::From(next_gen.as_bytes(), Direction::Forward)) {
             if !k.starts_with(gen.as_bytes()) {
                 info!("deleting stale key: {}", String::from_utf8_lossy(&k));
                 db.delete(k)?;
+                del_cnt += 1;
             }
         }
-        Ok(())
+        Ok(del_cnt)
     }
     pub fn create_album_index(&self, albums: &Vec<Album>) -> io::Result<()> {
         // Serialize it to a JSON string.
@@ -148,10 +154,10 @@ impl Library {
     pub fn generate_thumbnail(
         &self,
         media_items_id: &str,
-        dimensions: (u32, u32),
+        w: Option<u32>,
+        h: Option<u32>,
         filter: FilterType,
     ) -> Result<Vec<u8>, io::Error> {
-        let (w, h) = dimensions;
         match self.original(&media_items_id) {
             None => {
                 warn!("Couldn't find original {}", &media_items_id);
@@ -165,6 +171,12 @@ impl Library {
                     .with_guessed_format()?
                     .decode()
                     .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
+                let (orig_w, orig_h) = orig_img.dimensions();
+                let (w, h) = match (w, h) {
+                    (Some(w), Some(h)) => (w, h),
+                    (Some(w), None) => (w, orig_h * w / orig_w),
+                    (None, Some(h)) => (orig_w * h / orig_h, h),
+                };
                 let img = orig_img.resize_to_fill(w, h, filter);
                 let mut buf = Vec::new();
                 img.write_to(&mut buf, ImageFormat::Jpeg)