diff --git a/libvmaf/src/feature/feature_collector.c b/libvmaf/src/feature/feature_collector.c
index 42f4e340f..7b98100cd 100644
--- a/libvmaf/src/feature/feature_collector.c
+++ b/libvmaf/src/feature/feature_collector.c
@@ -355,61 +355,61 @@ int vmaf_feature_collector_append(VmafFeatureCollector *feature_collector,
 
     VmafPredictModel *model_iter = feature_collector->models;
 
-    while (model_iter) {
-        VmafModel *model = model_iter->model;
-        bool needs_computation = false;
+while (model_iter) {
+    VmafModel *model = model_iter->model;
+    bool needs_computation = false;
 
-        // Check if current score needs computation
+    // Check if current score needs computation
+    pthread_mutex_unlock(&(feature_collector->lock));
+    res = vmaf_feature_collector_get_score(feature_collector, model->name, &score, picture_index);
+    needs_computation = (res != 0);
+    pthread_mutex_lock(&(feature_collector->lock));
+
+    if (needs_computation) {
+        // Compute the current frame's score
         pthread_mutex_unlock(&(feature_collector->lock));
-        res = vmaf_feature_collector_get_score(feature_collector, model->name, &score, picture_index);
-        needs_computation = (res != 0);
+        res = vmaf_predict_score_at_index(model, feature_collector, picture_index, &score, true, true, 0);
         pthread_mutex_lock(&(feature_collector->lock));
 
-        if (needs_computation) {
-            // Compute the current frame's score
-            pthread_mutex_unlock(&(feature_collector->lock));
-            res = vmaf_predict_score_at_index(model, feature_collector, picture_index, &score, true, true, 0);
-            pthread_mutex_lock(&(feature_collector->lock));
-
-            if (!res) {
-                // Process all pending frames up to current index in order
-                unsigned process_index = feature_collector->metadata->last_seen_lowest_index;
-                feature_collector->metadata->last_seen_highest_index = MAX(picture_index, feature_collector->metadata->last_seen_highest_index);
-
-                while (process_index <= feature_collector->metadata->last_seen_highest_index) {
-                    bool frame_ready = true;
-
-                    // First check if this frame's score is ready
-                    pthread_mutex_unlock(&(feature_collector->lock));
-                    if (vmaf_feature_collector_get_score(feature_collector, model->name, &score, process_index) != 0) {
-                        frame_ready = false;
-                    }
-                    pthread_mutex_lock(&(feature_collector->lock));
-
-                    if (!frame_ready) break;  // Stop at first unready frame
-
-                    // Frame is ready, trigger callbacks for all features
-                    for (unsigned j = 0; j < feature_collector->cnt; j++) {
-                        VmafMetadata data = {
-                            .feature_name = feature_collector->feature_vector[j]->name,
-                            .picture_index = process_index,
-                            .score = feature_collector->feature_vector[j]->score[process_index].value,
-                        };
-
-                        // Call all metadata callbacks
-                        feature_collector->metadata->head->metadata_cfg.callback(
-                            feature_collector->metadata->head->metadata_cfg.data, &data);
-                    }
-
-                    process_index++;
-                    feature_collector->metadata->last_seen_lowest_index = process_index;
+        if (!res) {
+            // Process all pending frames up to current index in order
+            unsigned process_index = feature_collector->metadata->last_seen_lowest_index;
+            feature_collector->metadata->last_seen_highest_index = MAX(picture_index, feature_collector->metadata->last_seen_highest_index);
+
+            while (process_index <= feature_collector->metadata->last_seen_highest_index) {
+                bool frame_ready = true;
+
+                // First check if this frame's score is ready
+                pthread_mutex_unlock(&(feature_collector->lock));
+                if (vmaf_feature_collector_get_score(feature_collector, model->name, &score, process_index) != 0) {
+                    frame_ready = false;
                 }
+                pthread_mutex_lock(&(feature_collector->lock));
+
+                if (!frame_ready) break;  // Stop at first unready frame
+
+                // Frame is ready, trigger callbacks for all features
+                for (unsigned j = 0; j < feature_collector->cnt; j++) {
+                    VmafMetadata data = {
+                        .feature_name = feature_collector->feature_vector[j]->name,
+                        .picture_index = process_index,
+                        .score = feature_collector->feature_vector[j]->score[process_index].value,
+                    };
+
+                    // Call all metadata callbacks
+                    feature_collector->metadata->head->metadata_cfg.callback(
+                        feature_collector->metadata->head->metadata_cfg.data, &data);
+                }
+
+                process_index++;
+                feature_collector->metadata->last_seen_lowest_index = process_index;
             }
         }
-
-        model_iter = model_iter->next;
     }
 
+    model_iter = model_iter->next;
+}
+
 unlock:
     feature_collector->timer.end = clock();
     pthread_mutex_unlock(&(feature_collector->lock));