From 265571d7e2830de22f94c391db99dd921f956a23 Mon Sep 17 00:00:00 2001
From: TZGyn <spectator_brethren761@slmails.com>
Date: Wed, 9 Sep 2026 14:55:40 +0800
Subject: [PATCH] Reject window captures that composite extra windows
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ScreenCaptureKit's desktopIndependentWindow filter can include owned
child windows (e.g. an app dialog plus its parent), producing a capture
much larger than the picked window. Detect the overflow by comparing the
returned image size against the window's frame and fall back to the
screen crop with rounded mask. Hover changes are logged with the picked
window id and tracked count for diagnosis.

💘 Generated with Crush

Assisted-by: Crush:deepseek-v4-flash-0731
---
 Sources/Kapture/CaptureController.swift | 23 ++++++++++++++++++++---
 build-app.sh                            |  4 ++--
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/Sources/Kapture/CaptureController.swift b/Sources/Kapture/CaptureController.swift
index fa8557f..7c5d81f 100644
--- a/Sources/Kapture/CaptureController.swift
+++ b/Sources/Kapture/CaptureController.swift
@@ -287,6 +287,11 @@ final class CaptureController: NSObject {
                 let window = topmostWindowContaining(appKitPoint)
                 if window?.frame != hoverFrame {
                     hoverWindow = window
+                    if let w = window {
+                        CaptureController.log("hover: picked id=\(w.id) frame=\(w.frame) (tracked=\(trackedWindows.count))")
+                    } else {
+                        CaptureController.log("hover: none (tracked=\(trackedWindows.count))")
+                    }
                     renderOverlays()
                 }
                 return event
@@ -463,9 +468,21 @@ final class ScreenCapture {
                         contentFilter: SCContentFilter(desktopIndependentWindow: scWindow),
                         configuration: windowConfig
                     ) {
-                        CaptureController.log("capture: WINDOW id=\(windowID) image=\(windowImage.width)x\(windowImage.height) (native alpha corners)")
-                        completion(windowImage)
-                        return
+                        let expectedW = CGFloat(scWindow.frame.width) * backingScale
+                        let expectedH = CGFloat(scWindow.frame.height) * backingScale
+                        let overflow = max(
+                            CGFloat(windowImage.width) / max(expectedW, 1),
+                            CGFloat(windowImage.height) / max(expectedH, 1)
+                        )
+                        if overflow > 1.35 {
+                            // SCKit composited extra windows (owned popups etc.)
+                            // — reject and use the screen crop instead.
+                            CaptureController.log("capture: WINDOW id=\(windowID) overflow=\(overflow) (\(windowImage.width)x\(windowImage.height) vs \(Int(expectedW))x\(Int(expectedH))) — rejecting, using crop+mask")
+                        } else {
+                            CaptureController.log("capture: WINDOW id=\(windowID) image=\(windowImage.width)x\(windowImage.height) (native alpha corners)")
+                            completion(windowImage)
+                            return
+                        }
                     }
                     CaptureController.log("capture: window filter failed for id=\(windowID) — falling back to crop+mask")
                 }
diff --git a/build-app.sh b/build-app.sh
index a108ddd..ff2c134 100755
--- a/build-app.sh
+++ b/build-app.sh
@@ -108,9 +108,9 @@ cat > "$APP/Contents/Info.plist" <<'PLIST'
     <key>CFBundleIconFile</key>
     <string>Icon</string>
     <key>CFBundleShortVersionString</key>
-    <string>1.8.0</string>
+    <string>1.8.1</string>
     <key>CFBundleVersion</key>
-    <string>80</string>
+    <string>81</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>