Fix threshold values to avoid race condition (#220)

fix: pass threshold values

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

Author: asabri97

Sources/YOLO/YOLO.swift

@@ -19,6 +19,10 @@ import UIKit
 public class YOLO: @unchecked Sendable {
   var predictor: Predictor!
 
+  private var pendingNumItems: Int?
+  private var pendingConfidence: Double?
+  private var pendingIou: Double?
+
   /// Initialize YOLO with remote URL for automatic download and caching
   public init(url: URL, task: YOLOTask, completion: @escaping (Result<YOLO, Error>) -> Void) {
     let downloader = YOLOModelDownloader()
@@ -73,6 +77,12 @@ public class YOLO: @unchecked Sendable {
       switch result {
       case .success(let predictor):
         self.predictor = predictor
+        self.pendingNumItems.map { predictor.setNumItemsThreshold(numItems: $0) }
+        self.pendingConfidence.map { predictor.setConfidenceThreshold(confidence: $0) }
+        self.pendingIou.map { predictor.setIouThreshold(iou: $0) }
+        self.pendingNumItems = nil
+        self.pendingConfidence = nil
+        self.pendingIou = nil
         completion?(.success(self))
       case .failure(let error):
         print("Failed to load model with error: \(error)")
@@ -100,13 +110,14 @@ public class YOLO: @unchecked Sendable {
   /// Sets the maximum number of detection items to include in results.
   /// - Parameter numItems: The maximum number of items to include (default is 30).
   public func setNumItemsThreshold(_ numItems: Int) {
+    pendingNumItems = numItems
     (predictor as? BasePredictor)?.setNumItemsThreshold(numItems: numItems)
   }
 
   /// Gets the current maximum number of detection items.
   /// - Returns: The current threshold value, or nil if not applicable.
   public func getNumItemsThreshold() -> Int? {
-    (predictor as? BasePredictor)?.numItemsThreshold
+    (predictor as? BasePredictor)?.numItemsThreshold ?? pendingNumItems
   }
 
   /// Sets the confidence threshold for filtering results.
@@ -116,13 +127,14 @@ public class YOLO: @unchecked Sendable {
       print("Warning: Confidence threshold should be between 0.0 and 1.0")
       return
     }
+    pendingConfidence = confidence
     (predictor as? BasePredictor)?.setConfidenceThreshold(confidence: confidence)
   }
 
   /// Gets the current confidence threshold.
-  /// - Returns: The current confidence threshold value, or nil if not applicable.
+  /// - Returns: The current threshold value, or nil if not applicable.
   public func getConfidenceThreshold() -> Double? {
-    (predictor as? BasePredictor)?.confidenceThreshold
+    (predictor as? BasePredictor)?.confidenceThreshold ?? pendingConfidence
   }
 
   /// Sets the IoU (Intersection over Union) threshold for non-maximum suppression.
@@ -132,13 +144,14 @@ public class YOLO: @unchecked Sendable {
       print("Warning: IoU threshold should be between 0.0 and 1.0")
       return
     }
+    pendingIou = iou
     (predictor as? BasePredictor)?.setIouThreshold(iou: iou)
   }
 
   /// Gets the current IoU threshold.
-  /// - Returns: The current IoU threshold value, or nil if not applicable.
+  /// - Returns: The current threshold value, or nil if not applicable.
   public func getIouThreshold() -> Double? {
-    (predictor as? BasePredictor)?.iouThreshold
+    (predictor as? BasePredictor)?.iouThreshold ?? pendingIou
   }
 
   /// Sets all thresholds at once.