Fix: record audio from source URL, not microphone

Sources/PlayerBridge.swift

@@ -120,7 +120,10 @@ final class PlayerBridge: ObservableObject {
                 showToast("No video playing")
                 return
             }
-            screenRecorder.startRecording(from: output)
+            guard !queue.isEmpty else { return }
+            let sourceURL = queue[currentIndex].url
+            let startTime = player.currentTime()
+            screenRecorder.startRecording(from: output, sourceURL: sourceURL, startTime: startTime)
         }
         #endif
     }

Sources/PlayerRecorder.swift

@@ -2,7 +2,7 @@ import AVFoundation
 #if os(macOS)
 import AppKit
 
-/// 视频源录制器：从 AVPlayerItemVideoOutput 抓帧，用 AVAssetWriter 写入文件
+/// 视频源录制器：从 AVPlayerItemVideoOutput 抓帧 + 源 URL 音频轨道，写入 mp4
 @MainActor
 final class PlayerRecorder: NSObject {
     
@@ -11,8 +11,12 @@ final class PlayerRecorder: NSObject {
     private var audioInput: AVAssetWriterInput?
     private var timer: Timer?
     private var startDate: Date?
-    private var displayLink: CVDisplayLink?
     private var weakOutput: AVPlayerItemVideoOutput?
+    private var firstFrameTime: CMTime?
+    private var audioReader: AVAssetReader?
+    private var audioReaderOutput: AVAssetReaderTrackOutput?
+    private var audioCaptureQueue: DispatchQueue?
+    private var isRunning = false
     
     @Published var isRecording = false
     @Published var durationText = "00:00"
@@ -29,13 +33,15 @@ final class PlayerRecorder: NSObject {
         return dir
     }
     
-    /// 开始录制（从 videoOutput 抓帧）
+    /// 开始录制
-    func startRecording(from output: AVPlayerItemVideoOutput) {
+    func startRecording(from output: AVPlayerItemVideoOutput, sourceURL: URL, startTime: CMTime) {
         guard !isRecording else { return }
         
         weakOutput = output
+        firstFrameTime = nil
+        isRunning = false
         
-        // 创建临时文件
+        // 临时文件
         let formatter = DateFormatter()
         formatter.dateFormat = "yyyy-MM-dd_HH-mm-ss"
         let filename = "Recording_\(formatter.string(from: Date())).mp4"
@@ -49,6 +55,8 @@ final class PlayerRecorder: NSObject {
             return
         }
         
+        guard let writer = writer else { return }
+        
         // 视频输入
         let videoSettings: [String: Any] = [
             AVVideoCodecKey: AVVideoCodecType.h264,
@@ -57,25 +65,43 @@ final class PlayerRecorder: NSObject {
         ]
         let vInput = AVAssetWriterInput(mediaType: .video, outputSettings: videoSettings)
         vInput.expectsMediaDataInRealTime = true
-        if writer?.canAdd(vInput) == true {
+        if writer.canAdd(vInput) {
-            writer?.add(vInput)
+            writer.add(vInput)
             videoInput = vInput
         }
         
-        writer?.startWriting()
+        // 音频输入
-        writer?.startSession(atSourceTime: .zero)
+        let audioSettings: [String: Any] = [
+            AVFormatIDKey: kAudioFormatMPEG4AAC,
+            AVSampleRateKey: 44100,
+            AVNumberOfChannelsKey: 2,
+            AVEncoderBitRateKey: 128000
+        ]
+        let aInput = AVAssetWriterInput(mediaType: .audio, outputSettings: audioSettings)
+        aInput.expectsMediaDataInRealTime = true
+        if writer.canAdd(aInput) {
+            writer.add(aInput)
+            audioInput = aInput
+        }
         
+        writer.startWriting()
+        
+        // 启动视频抓帧
         isRecording = true
         startTimer()
         startCaptureLoop()
+        
+        // 启动音频读取（从源 URL）
+        startAudioCapture(sourceURL: sourceURL, startTime: startTime, audioWriterInput: aInput)
     }
     
     /// 停止录制
     func stopRecording() {
         guard isRecording else { return }
         isRecording = false
+        isRunning = false
         stopTimer()
-        stopCaptureLoop()
+        stopAudioCapture()
         
         videoInput?.markAsFinished()
         audioInput?.markAsFinished()
@@ -90,30 +116,51 @@ final class PlayerRecorder: NSObject {
         }
     }
     
-    // MARK: - 抓帧循环
+    // MARK: - 视频抓帧
     private func startCaptureLoop() {
-        let queue = DispatchQueue(label: "recorder.capture")
+        guard let vInput = videoInput else { return }
-        videoInput?.requestMediaDataWhenReady(on: queue) { [weak self] in
+        let queue = DispatchQueue(label: "recorder.video.capture")
-            self?.captureFrame()
+        vInput.requestMediaDataWhenReady(on: queue) { [weak self] in
-        }
+            guard let self = self, self.isRunning else { return }
-    }
+            Task { @MainActor in
-    
+                self.captureVideoFrame()
-    private func captureFrame() {
-        guard let output = weakOutput, let input = videoInput, input.isReadyForMoreMediaData else { return }
-        
-        let time = output.itemTime(forHostTime: CACurrentMediaTime())
-        if output.hasNewPixelBuffer(forItemTime: time), let pb = output.copyPixelBuffer(forItemTime: time, itemTimeForDisplay: nil) {
-            let sampleBuffer = createSampleBuffer(from: pb, time: time)
-            if let sb = sampleBuffer {
-                input.append(sb)
             }
         }
     }
     
-    private func createSampleBuffer(from pixelBuffer: CVPixelBuffer, time: CMTime) -> CMSampleBuffer? {
+    private func captureVideoFrame() {
+        guard let output = weakOutput, let input = videoInput, input.isReadyForMoreMediaData else { return }
+        
+        let hostTime = CACurrentMediaTime()
+        let itemTime = output.itemTime(forHostTime: hostTime)
+        
+        guard output.hasNewPixelBuffer(forItemTime: itemTime),
+              let pb = output.copyPixelBuffer(forItemTime: itemTime, itemTimeForDisplay: nil) else { return }
+        
+        // 第一帧：用它的时间作为 session 起点
+        if firstFrameTime == nil {
+            firstFrameTime = itemTime
+            writer?.startSession(atSourceTime: itemTime)
+            isRunning = true
+        }
+        
+        // 相对时间戳
+        guard let firstTime = firstFrameTime else { return }
+        let relativeTime = CMTimeSubtract(itemTime, firstTime)
+        
+        guard relativeTime.seconds >= 0 else { return }
+        
+        let sampleBuffer = Self.createSampleBuffer(from: pb, time: relativeTime)
+        if let sb = sampleBuffer {
+            _ = input.append(sb)
+        }
+    }
+    
+    private static func createSampleBuffer(from pixelBuffer: CVPixelBuffer, time: CMTime) -> CMSampleBuffer? {
         var info = CMSampleTimingInfo()
         info.presentationTimeStamp = time
         info.duration = CMTime(value: 1, timescale: 30)
+        info.decodeTimeStamp = .invalid
         
         var formatDescription: CMFormatDescription?
         CMVideoFormatDescriptionCreateForImageBuffer(allocator: kCFAllocatorDefault, imageBuffer: pixelBuffer, formatDescriptionOut: &formatDescription)
@@ -125,8 +172,97 @@ final class PlayerRecorder: NSObject {
         return sampleBuffer
     }
     
-    private func stopCaptureLoop() {
+    // MARK: - 音频读取（从源 URL）
-        // requestMediaDataWhenReady 会在 isReadyForMoreMediaData=false 时停止
+    private func startAudioCapture(sourceURL: URL, startTime: CMTime, audioWriterInput: AVAssetWriterInput) {
+        let asset = AVURLAsset(url: sourceURL)
+        
+        Task {
+            do {
+                let audioTracks = try await asset.loadTracks(withMediaType: .audio)
+                guard let audioTrack = audioTracks.first else {
+                    print("[Recorder] No audio track in source")
+                    return
+                }
+                
+                let reader = try AVAssetReader(asset: asset)
+                let output = AVAssetReaderTrackOutput(track: audioTrack, outputSettings: [
+                    AVFormatIDKey: kAudioFormatLinearPCM,
+                    AVSampleRateKey: 44100,
+                    AVNumberOfChannelsKey: 2,
+                    AVLinearPCMBitDepthKey: 16,
+                    AVLinearPCMIsFloatKey: false,
+                    AVLinearPCMIsBigEndianKey: false,
+                    AVLinearPCMIsNonInterleaved: false
+                ])
+                output.alwaysCopiesSampleData = false
+                
+                // 从播放位置开始读取
+                reader.timeRange = CMTimeRange(start: startTime, duration: .positiveInfinity)
+                
+                if reader.canAdd(output) {
+                    reader.add(output)
+                    reader.startReading()
+                    
+                    self.audioReader = reader
+                    self.audioReaderOutput = output
+                    
+                    // 后台线程读取音频
+                    let queue = DispatchQueue(label: "recorder.audio.capture")
+                    self.audioCaptureQueue = queue
+                    queue.async { [weak self] in
+                        self?.readAudioLoop(reader: reader, output: output)
+                    }
+                }
+            } catch {
+                print("[Recorder] Audio capture setup failed: \(error)")
+            }
+        }
+    }
+    
+    private nonisolated func readAudioLoop(reader: AVAssetReader, output: AVAssetReaderTrackOutput) {
+        while reader.status == .reading {
+            guard let sampleBuffer = output.copyNextSampleBuffer() else {
+                break
+            }
+            
+            // 在 MainActor 上调整时间戳并写入
+            Task { @MainActor [weak self] in
+                guard let self = self, self.isRunning else { return }
+                guard let firstTime = self.firstFrameTime else { return }
+                guard let input = self.audioInput, input.isReadyForMoreMediaData else { return }
+                
+                let pts = CMSampleBufferGetPresentationTimeStamp(sampleBuffer)
+                let relativeTime = CMTimeSubtract(pts, firstTime)
+                guard relativeTime.seconds >= 0 else { return }
+                
+                // 重建 sample buffer with new time
+                var count: CMItemCount = 0
+                CMSampleBufferGetSampleTimingInfoArray(sampleBuffer, entryCount: 0, arrayToFill: nil, entriesNeededOut: &count)
+                var timingInfo = [CMSampleTimingInfo](repeating: CMSampleTimingInfo(), count: count)
+                CMSampleBufferGetSampleTimingInfoArray(sampleBuffer, entryCount: count, arrayToFill: &timingInfo, entriesNeededOut: nil)
+                
+                for i in 0..<count {
+                    timingInfo[i].decodeTimeStamp = .invalid
+                    timingInfo[i].presentationTimeStamp = CMTimeSubtract(timingInfo[i].presentationTimeStamp, firstTime)
+                }
+                
+                var newBuffer: CMSampleBuffer?
+                CMSampleBufferCreateCopyWithNewTiming(allocator: kCFAllocatorDefault, sampleBuffer: sampleBuffer, sampleTimingEntryCount: count, sampleTimingArray: &timingInfo, sampleBufferOut: &newBuffer)
+                
+                if let nb = newBuffer {
+                    _ = input.append(nb)
+                }
+            }
+            
+            // 等待 MainActor 处理完
+            Thread.sleep(forTimeInterval: 0.005)
+        }
+    }
+    
+    private func stopAudioCapture() {
+        audioReader?.cancelReading()
+        audioReader = nil
+        audioReaderOutput = nil
     }
     
     // MARK: - Timer