amitv87 · ccarpiog · Nov 27, 2025 · Feb 3, 2026 · Feb 3, 2026 · Feb 3, 2026
diff --git a/.claude/settings.json b/.claude/settings.json
@@ -0,0 +1,9 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(lsof:*)",
+      "Bash(log show:*)",
+      "Read(//Users/ccarpio/Library/Developer/Xcode/DerivedData/**)"
+    ]
+  }
+}
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -7,14 +7,14 @@ set(CMAKE_OSX_DEPLOYMENT_TARGET 11.0)
 
 project(PiP)
 
-add_compile_options(-fobjc-arc -Wno-deprecated-declarations -Wno-format)
+add_compile_options(-fobjc-arc -Wno-deprecated-declarations -Wno-format -mmacosx-version-min=14.0)
 
 set(frameworks AVFoundation Cocoa VideoToolbox AudioToolbox CoreMedia QuartzCore OpenGL Metal MetalKit PIP SkyLight ScreenCaptureKit)
 list(TRANSFORM frameworks PREPEND "-framework ")
 
 set(AIRPLAY_SUPPORT_ENABLED 1)
 
-file(GLOB_RECURSE pip_src CONFIGURE_DEPENDS "pip/*.m")
+file(GLOB_RECURSE pip_src CONFIGURE_DEPENDS "pip/*.m" "pip/*.c")
 add_executable(pip ${pip_src})
 target_include_directories(pip PRIVATE
   ${CMAKE_CURRENT_SOURCE_DIR}

diff --git a/LICENSE b/LICENSE
@@ -1,6 +1,7 @@
 MIT License
 
 Copyright (c) 2020 amitv87
+Copyright (c) 2026 ccarpiog
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

diff --git a/README.md b/README.md
@@ -18,8 +18,8 @@ Always on top window preview with AirPlay receiver support (if on macOS 12+, tur
 ## Features
 * Clone any visibile window
 * Clone multiple active display
-* Camera preview
-* HLS streaming
+* Camera preview with audio monitoring
+* HLS live streaming of any preview (window, display, or camera)
 * Airplay sender (unstable)
 * Crop the preview
 * Auto and manual resize preserving the aspect ratio
@@ -30,6 +30,40 @@ Always on top window preview with AirPlay receiver support (if on macOS 12+, tur
 * Minimal modern UI
 * Upto 10 parallel airplay sessions (soft limit)
 
+## Live Streaming
+
+PiP can stream any preview window over your local network using HLS (HTTP Live Streaming). Any device with a web browser on the same network can watch the live feed.
+
+### How to use
+1. Right-click any active preview window and select **Stream > Start Streaming**
+2. The stream URL (e.g. `http://192.168.1.42:8080`) appears at the bottom of the Stream menu
+3. Open that URL on any device's browser to watch the live stream
+4. Use **Copy URL** to copy the direct HLS stream URL (`/stream.m3u8`) or **Open in Browser** to open the web viewer
+
+### Quality presets
+| Preset | Resolution | Bitrate | FPS |
+|--------|-----------|---------|-----|
+| Low    | 720p      | 1.5 Mbps | 24 |
+| Medium | 1080p     | 3 Mbps   | 30 |
+| High   | Native    | 6 Mbps   | 30 |
+
+Change quality on the fly via **Stream > Quality**.
+
+### Architecture
+The streaming pipeline is fully self-contained with no third-party dependencies:
+
+```
+Frame Capture → H.264 Video Encoder → MPEG-TS Muxer → HLS Writer → HTTP Server
+                                             ↑
+                                       Audio Capture
+```
+
+* **Frame Capture** – grabs RGBA frames from the preview's OpenGL/Metal renderer
+* **Video Encoder** – hardware-accelerated H.264 encoding via VideoToolbox
+* **TS Muxer** – multiplexes video (and optional audio) into MPEG-TS segments
+* **HLS Writer** – manages a ring buffer of `.ts` segments and generates the `.m3u8` playlist
+* **HTTP Server** – lightweight embedded server that serves the playlist, segments, and a built-in web viewer with hls.js
+
 ## Installation
 
 ### Manual download

diff --git a/airplay_sender/video_encoder.h b/airplay_sender/video_encoder.h
@@ -60,6 +60,13 @@ video_encoder_t *video_encoder_init(int width, int height, int fps, int bitrate)
  */
 void video_encoder_set_callback(video_encoder_t *enc, encoded_frame_callback_t cb, void *ctx);
 
+/**
+ * Set maximum keyframe interval in frames.
+ * Example: at 30fps, 30 => ~1 second keyframe cadence.
+ * Returns 0 on success, -1 on error.
+ */
+int video_encoder_set_keyframe_interval(video_encoder_t *enc, int keyframe_interval_frames);
+
 /**
  * Encode a frame
  * rgba_data: RGBA32 format frame data (row-major)
@@ -78,4 +85,4 @@ void video_encoder_destroy(video_encoder_t *enc);
 }
 #endif
 
-#endif
+#endif
diff --git a/airplay_sender/video_encoder_stub.c b/airplay_sender/video_encoder_stub.c
@@ -44,6 +44,14 @@ video_encoder_set_callback(video_encoder_t *enc, encoded_frame_callback_t cb, vo
   }
 }
 
+int
+video_encoder_set_keyframe_interval(video_encoder_t *enc, int keyframe_interval_frames)
+{
+  (void)enc;
+  (void)keyframe_interval_frames;
+  return 0;
+}
+
 int
 video_encoder_encode_frame(video_encoder_t *enc, uint8_t *rgba_data, int stride, uint64_t pts)
 {

diff --git a/pip.xcodeproj/project.pbxproj b/pip.xcodeproj/project.pbxproj
@@ -147,6 +147,10 @@
 		55FEB9A7 /* airplaySender.m in Sources */ = {isa = PBXBuildFile; fileRef = 55FEB9A2 /* airplaySender.m */; };
 		55FEB9A8 /* frame_capture.m in Sources */ = {isa = PBXBuildFile; fileRef = 55FEB9A4 /* frame_capture.m */; };
 		55FEB9A9 /* video_encoder.m in Sources */ = {isa = PBXBuildFile; fileRef = 55FEB9A6 /* video_encoder.m */; };
+		55FEBC11 /* ts_muxer.c in Sources */ = {isa = PBXBuildFile; fileRef = 55FEBC02 /* ts_muxer.c */; };
+		55FEBC12 /* hls_writer.c in Sources */ = {isa = PBXBuildFile; fileRef = 55FEBC04 /* hls_writer.c */; };
+		55FEBC13 /* stream_server.m in Sources */ = {isa = PBXBuildFile; fileRef = 55FEBC06 /* stream_server.m */; };
+		55FEBC14 /* stream_manager.m in Sources */ = {isa = PBXBuildFile; fileRef = 55FEBC08 /* stream_manager.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -325,6 +329,17 @@
 		55FEB9A5 /* video_encoder.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = video_encoder.h; sourceTree = "<group>"; };
 		55FEB9A6 /* video_encoder.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = video_encoder.m; sourceTree = "<group>"; };
 		55FEB9AA /* ScreenCaptureKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = ScreenCaptureKit.framework; path = /System/Volumes/Data/Library/Developer/CommandLineTools/SDKs/MacOSX12.3.sdk/System/Library/Frameworks/ScreenCaptureKit.framework; sourceTree = "<group>"; };
+		55FEBC01 /* ts_muxer.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ts_muxer.h; sourceTree = "<group>"; };
+		55FEBC02 /* ts_muxer.c */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.c; path = ts_muxer.c; sourceTree = "<group>"; };
+		55FEBC03 /* hls_writer.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = hls_writer.h; sourceTree = "<group>"; };
+		55FEBC04 /* hls_writer.c */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.c; path = hls_writer.c; sourceTree = "<group>"; };
+		55FEBC05 /* stream_server.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = stream_server.h; sourceTree = "<group>"; };
+		55FEBC06 /* stream_server.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = stream_server.m; sourceTree = "<group>"; };
+		55FEBC07 /* stream_manager.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = stream_manager.h; sourceTree = "<group>"; };
+		55FEBC08 /* stream_manager.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = stream_manager.m; sourceTree = "<group>"; };
+		55FEBC09 /* viewer.html */ = {isa = PBXFileReference; lastKnownFileType = text.html; path = viewer.html; sourceTree = "<group>"; };
+		55FEBC0A /* hls.min.js */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.javascript; path = "hls.min.js"; sourceTree = "<group>"; };
+		55FEBC0B /* incbin.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = incbin.h; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -576,6 +591,17 @@
 				55FEB9A4 /* frame_capture.m */,
 				55FEB9A5 /* video_encoder.h */,
 				55FEB9A6 /* video_encoder.m */,
+				55FEBC01 /* ts_muxer.h */,
+				55FEBC02 /* ts_muxer.c */,
+				55FEBC03 /* hls_writer.h */,
+				55FEBC04 /* hls_writer.c */,
+				55FEBC05 /* stream_server.h */,
+				55FEBC06 /* stream_server.m */,
+				55FEBC07 /* stream_manager.h */,
+				55FEBC08 /* stream_manager.m */,
+				55FEBC09 /* viewer.html */,
+				55FEBC0A /* hls.min.js */,
+				55FEBC0B /* incbin.h */,
 			);
 			path = pip;
 			sourceTree = "<group>";
@@ -807,6 +833,10 @@
 				55FEB9A7 /* airplaySender.m in Sources */,
 				55FEB9A8 /* frame_capture.m in Sources */,
 				55FEB9A9 /* video_encoder.m in Sources */,
+				55FEBC11 /* ts_muxer.c in Sources */,
+				55FEBC12 /* hls_writer.c in Sources */,
+				55FEBC13 /* stream_server.m in Sources */,
+				55FEBC14 /* stream_manager.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

diff --git a/pip/HLSPlayer.m b/pip/HLSPlayer.m
@@ -33,6 +33,8 @@ - (instancetype)initWithURL:(NSURL *)url headers:(NSDictionary<NSString *, NSStr
 
     _playerItem = [AVPlayerItem playerItemWithAsset:asset];
     _player = [AVPlayer playerWithPlayerItem:_playerItem];
+    _player.automaticallyWaitsToMinimizeStalling = NO;
+    _playerItem.preferredForwardBufferDuration = 1.0;
 
     // Setup video output for frame extraction
     NSDictionary *pixBuffAttributes = @{

diff --git a/pip/frame_capture.m b/pip/frame_capture.m
@@ -96,17 +96,29 @@ static void capture_frame(frame_capture_t *cap) {
     return;
   }
 
-  // Get the current image from the renderer (must be on main thread)
-  // __block CIImage *currentImage = nil;
-  // if ([NSThread isMainThread]) {
-  //   currentImage = [imageView.renderer currentImage];
-  // } else {
-  //   dispatch_sync(dispatch_get_main_queue(), ^{
-  //     currentImage = [imageView.renderer currentImage];
-  //   });
-  // }
-
-  __block CIImage *currentImage = [imageView.renderer currentImage];
+  // Get the current image from the renderer on main thread.
+  // Use a bounded wait when called from the capture queue to avoid deadlock
+  // during shutdown (main thread stopping capture while capture queue requests main).
+  __block CIImage *currentImage = nil;
+  if ([NSThread isMainThread]) {
+    currentImage = [imageView.renderer currentImage];
+  } else {
+    dispatch_semaphore_t sem = dispatch_semaphore_create(0);
+    dispatch_async(dispatch_get_main_queue(), ^{
+      currentImage = [imageView.renderer currentImage];
+      dispatch_semaphore_signal(sem);
+    });
+    long wait_result = dispatch_semaphore_wait(
+      sem,
+      dispatch_time(DISPATCH_TIME_NOW, (int64_t)(50 * NSEC_PER_MSEC))
+    );
+    if (wait_result != 0) {
+      if (cap->frame_count == 0 || cap->frame_count % 30 == 0) {
+        NSLog(@"frame_capture: timed out waiting for main-thread image (frame_count: %llu)", cap->frame_count);
+      }
+      return;
+    }
+  }
 
   if (!currentImage) {
     if (cap->frame_count == 0 || cap->frame_count % 30 == 0) {

diff --git a/pip/hls.min.js b/pip/hls.min.js