From baf76c9b9e5349c2069f19f04ceb48ce3952fef6 Mon Sep 17 00:00:00 2001
From: Ryan Romanchuk <ryan@romanch.uk>
Date: Mon, 29 May 2023 21:45:08 -0500
Subject: [PATCH 1/2] allow configurable qos

---
 Sources/NextLevelSessionExporter.swift | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Sources/NextLevelSessionExporter.swift b/Sources/NextLevelSessionExporter.swift
index b56338f..d7525ba 100644
--- a/Sources/NextLevelSessionExporter.swift
+++ b/Sources/NextLevelSessionExporter.swift
@@ -90,6 +90,9 @@ open class NextLevelSessionExporter: NSObject {
     /// Audio output configuration dictionary, using keys defined in `<AVFoundation/AVAudioSettings.h>`
     public var audioOutputConfiguration: [String : Any]?
     
+    /// Assign custom priority on global dispatch queue
+    public var qos: DispatchQoS.QoSClass = .default
+    
     /// Export session status state.
     public var status: AVAssetExportSession.Status {
         get {
@@ -302,7 +305,7 @@ extension NextLevelSessionExporter {
             audioSemaphore.signal()
         }
         
-        DispatchQueue.global().async {
+        DispatchQueue.global(qos: qos).async {
             audioSemaphore.wait()
             videoSemaphore.wait()
             DispatchQueue.main.async {

From 75cad73f3d369abd8488debe707c9a8b69f7a9b6 Mon Sep 17 00:00:00 2001
From: Ryan Romanchuk <ryan@romanch.uk>
Date: Mon, 29 May 2023 22:13:00 -0500
Subject: [PATCH 2/2] try again

---
 Sources/NextLevelSessionExporter.swift | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/Sources/NextLevelSessionExporter.swift b/Sources/NextLevelSessionExporter.swift
index d7525ba..cbf3ae5 100644
--- a/Sources/NextLevelSessionExporter.swift
+++ b/Sources/NextLevelSessionExporter.swift
@@ -90,8 +90,7 @@ open class NextLevelSessionExporter: NSObject {
     /// Audio output configuration dictionary, using keys defined in `<AVFoundation/AVAudioSettings.h>`
     public var audioOutputConfiguration: [String : Any]?
     
-    /// Assign custom priority on global dispatch queue
-    public var qos: DispatchQoS.QoSClass = .default
+    
     
     /// Export session status state.
     public var status: AVAssetExportSession.Status {
@@ -132,6 +131,8 @@ open class NextLevelSessionExporter: NSObject {
     fileprivate var _pixelBufferAdaptor: AVAssetWriterInputPixelBufferAdaptor?
     
     fileprivate var _inputQueue: DispatchQueue
+    /// Assign custom priority on global dispatch queue
+    fileprivate var _qos: DispatchQoS.QoSClass
     
     fileprivate var _videoOutput: AVAssetReaderVideoCompositionOutput?
     fileprivate var _audioOutput: AVAssetReaderAudioMixOutput?
@@ -152,13 +153,21 @@ open class NextLevelSessionExporter: NSObject {
     /// Initializes a session with an asset to export.
     ///
     /// - Parameter asset: The asset to export.
-    public convenience init(withAsset asset: AVAsset) {
-        self.init()
+    public convenience init(withAsset asset: AVAsset, qos: DispatchQoS.QoSClass = .default) {
+        self.init(qos: qos)
         self.asset = asset
     }
     
+    public init(qos: DispatchQoS.QoSClass) {
+        self._qos = qos
+        self._inputQueue = DispatchQueue(label: InputQueueLabel, autoreleaseFrequency: .workItem, target: DispatchQueue.global(qos: _qos))
+        self.timeRange = CMTimeRange(start: CMTime.zero, end: CMTime.positiveInfinity)
+        super.init()
+    }
+    
     public override init() {
-        self._inputQueue = DispatchQueue(label: InputQueueLabel, autoreleaseFrequency: .workItem, target: DispatchQueue.global())
+        self._qos = .default
+        self._inputQueue = DispatchQueue(label: InputQueueLabel, autoreleaseFrequency: .workItem, target: DispatchQueue.global(qos: _qos))
         self.timeRange = CMTimeRange(start: CMTime.zero, end: CMTime.positiveInfinity)
         super.init()
     }
@@ -305,7 +314,7 @@ extension NextLevelSessionExporter {
             audioSemaphore.signal()
         }
         
-        DispatchQueue.global(qos: qos).async {
+        DispatchQueue.global(qos: _qos).async {
             audioSemaphore.wait()
             videoSemaphore.wait()
             DispatchQueue.main.async {