feat: suppoer heics file

Sources/Gifu/Classes/Animator.swift

@@ -37,9 +37,15 @@ public class Animator {
   private lazy var displayLink: CADisplayLink = { [unowned self] in
     self.displayLinkInitialized = true
     let display = CADisplayLink(target: DisplayLinkProxy(target: self), selector: #selector(DisplayLinkProxy.onScreenUpdate))
+      if #available(iOS 15.0, *) {
+          display.preferredFramesPerSecond = 60
+//          display.preferredFrameRateRange = .init(minimum: 1/120, maximum: 1/120)
+      }
     display.isPaused = true
     return display
   }()
+
+    var lastTime: CFTimeInterval?
 
   /// Introspect whether the `displayLink` is paused.
   var isAnimating: Bool {
@@ -71,7 +77,13 @@ public class Animator {
         return
     }
 
-    store.shouldChangeFrame(with: displayLink.duration) {
+      var duration = displayLink.duration
+      if let lastTime {
+          duration = displayLink.targetTimestamp - lastTime
+      }
+      lastTime = displayLink.targetTimestamp
+
+    store.shouldChangeFrame(with: duration) {
       if $0 {
           delegate.animatorHasNewFrame()
           if store.isLoopFinished, let loopBlock = loopBlock {

Sources/Gifu/Classes/FrameStore.swift

@@ -84,6 +84,8 @@ class FrameStore {
   }
 
   private let lock = NSLock()
+
+    var lastTime: Date?
 
   /// Creates an animator instance from raw GIF image data and an `Animatable` delegate.
   ///
@@ -141,8 +143,11 @@ class FrameStore {
     if currentFrameDuration > timeSinceLastFrameChange {
       handler(false)
     } else {
-      resetTimeSinceLastFrameChange()
-      incrementCurrentFrameIndex()
+        while timeSinceLastFrameChange > currentFrameDuration {
+            resetTimeSinceLastFrameChange()
+            incrementCurrentFrameIndex()
+        }
+
       handler(true)
     }
   }

Sources/Gifu/Helpers/ImageSourceHelpers.swift

@@ -63,22 +63,42 @@ func duration(withUnclampedTime unclampedDelayTime: Double, andClampedTime delay
 
 /// An extension of `CGImageSourceRef` that adds GIF introspection and easier property retrieval.
 extension CGImageSource {
+
+    var isTypeGIF: Bool {
+        UTTypeConformsTo(CGImageSourceGetType(self) ?? "" as CFString, kUTTypeGIF)
+    }
+
+    var isTypeHEICS: Bool {
+        UTTypeConformsTo(CGImageSourceGetType(self) ?? "" as CFString, "public.heics" as CFString)
+    }
+
   /// Returns whether the image source contains an animated GIF.
   ///
   /// - returns: A boolean value that is `true` if the image source contains animated GIF data.
   var isAnimatedGIF: Bool {
-    let isTypeGIF = UTTypeConformsTo(CGImageSourceGetType(self) ?? "" as CFString, kUTTypeGIF)
     let imageCount = CGImageSourceGetCount(self)
-    return isTypeGIF != false && imageCount > 1
+    return imageCount > 1
   }
 
   /// Returns the GIF properties at a specific index.
   ///
   /// - parameter index: The index of the GIF properties to retrieve.
   /// - returns: A dictionary containing the GIF properties at the passed in index.
   func properties(at index: Int) -> GIFProperties? {
-    guard let imageProperties = CGImageSourceCopyPropertiesAtIndex(self, index, nil) as? [String: AnyObject] else { return nil }
-    return imageProperties[String(kCGImagePropertyGIFDictionary)] as? GIFProperties
+      CGImageSourceGetType(self)
+      if isTypeGIF {
+          guard let imageProperties = CGImageSourceCopyPropertiesAtIndex(self, index, nil) as? [String: AnyObject] else { return nil }
+          return imageProperties[String(kCGImagePropertyGIFDictionary)] as? GIFProperties
+      } else if isTypeHEICS {
+          guard let imageProperties = CGImageSourceCopyPropertiesAtIndex(self, index, nil) as? [String: AnyObject] else { return nil }
+          if #available(iOS 13.0, *) {
+              return imageProperties[String(kCGImagePropertyHEICSDictionary)] as? GIFProperties
+          } else {
+              return nil
+          }
+      } else {
+          return nil
+      }
   }
 }