fix

Author: master-of-zen

src/scenechange/mod.rs

@@ -136,12 +136,15 @@ impl<T: Pixel> SceneChangeDetector<T> {
     }
 
     // Decrease deque offset if there is no more frames
-    if self.deque_offset > frame_set.len() && self.lookahead_offset > 0 {
+    if self.deque_offset > frame_set.len() + 1 && self.lookahead_offset > 0 {
       self.deque_offset = frame_set.len();
     }
 
     // Initially fill score deque with forward frames
-    if self.deque_offset > 0 && self.score_deque.len() == 0 {
+    if self.deque_offset > 0
+      && self.score_deque.is_empty()
+      && frame_set.len() > self.lookahead_offset + 1
+    {
       for x in 0..self.lookahead_offset {
         // Filling score deque with forward frames
         let result = if self.fast_mode {
@@ -156,35 +159,36 @@ impl<T: Pixel> SceneChangeDetector<T> {
         };
         self.score_deque.push((result.inter_cost, result.intra_cost));
       }
-      debug!("{:.0?}", self.score_deque)
     }
 
     // Running single frame comparison and adding it to deque
-    let result = if self.fast_mode {
-      self.fast_scenecut(
-        frame_set[0 + self.deque_offset].clone(),
-        frame_set[1 + self.deque_offset].clone(),
-      )
-    } else {
-      self.cost_scenecut(
-        frame_set[0 + self.deque_offset].clone(),
-        frame_set[1 + self.deque_offset].clone(),
-        input_frameno,
-        previous_keyframe,
-      )
-    };
-    self
-      .score_deque
-      .push((result.inter_cost as f64, result.intra_cost as f64));
+    if frame_set.len() > self.deque_offset + 1 {
+      let result = if self.fast_mode {
+        self.fast_scenecut(
+          frame_set[self.deque_offset].clone(),
+          frame_set[self.deque_offset + 1].clone(),
+        )
+      } else {
+        self.cost_scenecut(
+          frame_set[self.deque_offset].clone(),
+          frame_set[self.deque_offset + 1].clone(),
+          input_frameno,
+          previous_keyframe,
+        )
+      };
+      self
+        .score_deque
+        .push((result.inter_cost as f64, result.intra_cost as f64));
+    }
 
-    // Adaptive scenecut check;
+    // Adaptive scenecut check
     let scenecut = self.adaptive_scenecut();
 
     debug!(
       "[SC-Detect] Frame {}: Cost={:.0}  Threshold= {:.0} {}",
       input_frameno,
-      self.score_deque[self.score_deque.len() - self.deque_offset].0,
-      self.score_deque[self.score_deque.len() - self.deque_offset].1,
+      self.score_deque[self.score_deque.len() - (self.deque_offset + 1)].0,
+      self.score_deque[self.score_deque.len() - (self.deque_offset + 1)].1,
       if scenecut { "Scenecut" } else { "No cut" }
     );
 
@@ -194,13 +198,11 @@ impl<T: Pixel> SceneChangeDetector<T> {
 
       // Clear buffers and deque
       self.frame_buffer.clear();
+      debug!("[SC-score-deque]{:.0?}", self.score_deque);
       self.score_deque.clear();
     } else {
       // Keep score deque 5 + lookahead_size frames
-      self
-        .score_deque
-        .push((result.inter_cost as f64, result.intra_cost as f64));
-      if self.score_deque.len() > 5 + self.deque_offset {
+      if self.score_deque.len() > 5 + self.lookahead_offset {
         self.score_deque.remove(0);
       }
     }
@@ -228,10 +230,9 @@ impl<T: Pixel> SceneChangeDetector<T> {
     };
 
     let scene_score =
-      self.score_deque[self.score_deque.len() - self.deque_offset].0;
+      self.score_deque[self.score_deque.len() - (self.deque_offset + 1)].0;
 
-    let scenecut = scene_score >= threshold;
-    scenecut
+    scene_score >= threshold
   }
 
   /// The fast algorithm detects fast cuts using a raw difference