fix: Frame Processor FPS (#1288)

* fix: Build using XCode 14

* fix: Throttle FP by start time rather than end time

example/ios/Podfile

@@ -16,5 +16,17 @@ target 'VisionCameraExample' do
   post_install do |installer|
     react_native_post_install(installer)
     __apply_Xcode_12_5_M1_post_install_workaround(installer)
+    
+    # This is necessary for Xcode 14, because it signs resource bundles by default
+    # when building for devices. See https://github.com/facebook/react-native/issues/34673#issuecomment-1259253787
+    installer.target_installation_results.pod_target_installation_results
+      .each do |pod_name, target_installation_result|
+      target_installation_result.resource_bundle_targets.each do |resource_bundle_target|
+        resource_bundle_target.build_configurations.each do |config|
+          config.build_settings['CODE_SIGNING_ALLOWED'] = 'NO'
+        end
+      end
+    end
+      
   end
 end

example/ios/Podfile.lock

@@ -324,7 +324,7 @@ PODS:
     - React
   - RNVectorIcons (8.1.0):
     - React-Core
-  - VisionCamera (2.13.3):
+  - VisionCamera (2.14.0):
     - React
     - React-callinvoker
     - React-Core
@@ -504,9 +504,9 @@ SPEC CHECKSUMS:
   RNScreens: 40a2cb40a02a609938137a1e0acfbf8fc9eebf19
   RNStaticSafeAreaInsets: 6103cf09647fa427186d30f67b0f5163c1ae8252
   RNVectorIcons: 31cebfcf94e8cf8686eb5303ae0357da64d7a5a4
-  VisionCamera: 7bcf3a81533a1c9ad13930804377ad13a03fcded
+  VisionCamera: 17d4ce16a6b3646081005292e2ee0e972b5233c9
   Yoga: e7dc4e71caba6472ff48ad7d234389b91dadc280
 
-PODFILE CHECKSUM: 29b1752e05601e9867644e58ce0ed8b9106be6cb
+PODFILE CHECKSUM: d3dcba1fba41a8301df6697eb0ddc5cfe4ea2cc8
 
 COCOAPODS: 1.10.2

ios/CameraView+RecordVideo.swift

@@ -212,11 +212,11 @@ extension CameraView: AVCaptureVideoDataOutputSampleBufferDelegate, AVCaptureAud
 
     if let frameProcessor = frameProcessorCallback, captureOutput is AVCaptureVideoDataOutput {
       // check if last frame was x nanoseconds ago, effectively throttling FPS
-      let lastFrameProcessorCallElapsedTime = DispatchTime.now().uptimeNanoseconds - lastFrameProcessorCall.uptimeNanoseconds
+      let frameTime = UInt64(CMSampleBufferGetPresentationTimeStamp(sampleBuffer).seconds * 1_000_000_000.0)
+      let lastFrameProcessorCallElapsedTime = frameTime - lastFrameProcessorCall
       let secondsPerFrame = 1.0 / actualFrameProcessorFps
       let nanosecondsPerFrame = secondsPerFrame * 1_000_000_000.0
-
+      if lastFrameProcessorCallElapsedTime >= UInt64(nanosecondsPerFrame) {
-      if lastFrameProcessorCallElapsedTime > UInt64(nanosecondsPerFrame) {
         if !isRunningFrameProcessor {
           // we're not in the middle of executing the Frame Processor, so prepare for next call.
           CameraQueues.frameProcessorQueue.async {
@@ -229,7 +229,7 @@ extension CameraView: AVCaptureVideoDataOutputSampleBufferDelegate, AVCaptureAud
 
             self.isRunningFrameProcessor = false
           }
-          lastFrameProcessorCall = DispatchTime.now()
+          lastFrameProcessorCall = frameTime
         } else {
           // we're still in the middle of executing a Frame Processor for a previous frame, so a frame was dropped.
           ReactLogger.log(level: .warning, message: "The Frame Processor took so long to execute that a frame was dropped.")

ios/CameraView.swift

@@ -94,7 +94,7 @@ public final class CameraView: UIView {
   internal var isRecording = false
   internal var recordingSession: RecordingSession?
   @objc public var frameProcessorCallback: FrameProcessorCallback?
-  internal var lastFrameProcessorCall = DispatchTime.now()
+  internal var lastFrameProcessorCall = DispatchTime.now().uptimeNanoseconds
   // CameraView+TakePhoto
   internal var photoCaptureDelegates: [PhotoCaptureDelegate] = []
   // CameraView+Zoom