fix keyframe warn logic

https://github.com/mifi/lossless-cut/issues/2804#issuecomment-4082777771

src/renderer/src/App.tsx

@@ -1532,10 +1532,11 @@ function App() {
   const toggleSettings = useCallback(() => setSettingsVisible((val) => !val), []);
 
   const seekClosestKeyframe = useCallback((direction: number) => {
-    const time = findNearestKeyFrameTime({ time: getRelevantTime(), direction });
+    const sigma = detectedFps ? (1 / detectedFps) : 0.1; // because we don't want it to find the keyframe we're currently at.
+    const time = findNearestKeyFrameTime({ time: getRelevantTime() + direction * sigma, direction });
     if (time == null) return;
     seekAbs(time);
-  }, [findNearestKeyFrameTime, getRelevantTime, seekAbs]);
+  }, [detectedFps, findNearestKeyFrameTime, getRelevantTime, seekAbs]);
 
   const onTimelineWheel = useTimelineScroll({ wheelSensitivity, mouseWheelZoomModifierKey, mouseWheelFrameSeekModifierKey, mouseWheelKeyframeSeekModifierKey, invertTimelineScroll, zoomRel, seekRel, shortStep, seekClosestKeyframe });
 

src/renderer/src/components/ExportConfirm.tsx

@@ -170,11 +170,12 @@ function ExportConfirm({
   const areWeCuttingProblematicStreams = areWeCutting && mainCopiedThumbnailStreams.length > 0;
 
   const haveSegmentWithProblematicKeyframe = useMemo(() => {
-    if (neighbouringKeyFrames.length === 0) return false;
+    if (neighbouringKeyFrames.length === 0) return false; // we don't know
     return segmentsToExport.some(({ start, end }) => {
-      const previousKeyframeTime = findNearestKeyFrameTime({ time: start, direction: -1 }) ?? 0;
+      const nearestPreviousKeyframeTime = findNearestKeyFrameTime({ time: start, direction: -1 }) ?? 0;
+      console.log({start,end,nearestPreviousKeyframeTime})
       const segmentDuration = end - start;
-      const estimatedExportedSegmentDuration = end - previousKeyframeTime;
+      const estimatedExportedSegmentDuration = end - nearestPreviousKeyframeTime;
       // if estimated actual output length of segment is more than 1.5 times the intended segment duration, then we consider it problematic and warn the user about it.
       return estimatedExportedSegmentDuration > segmentDuration * 1.5;
     });

src/renderer/src/ffmpeg.ts

@@ -191,9 +191,8 @@ export function getSafeCutTime(frames: Frame[], cutTime: number, nextMode: boole
   return frames[index - 1]!.time;
 }
 
-export function findNearestKeyFrameTime({ frames, time, direction, fps }: { frames: Frame[], time: number, direction: number, fps: number | undefined }) {
-  const sigma = fps ? (1 / fps) : 0.1;
-  const keyframes = frames.filter((f) => f.keyframe && (direction > 0 ? f.time > time + sigma : f.time < time - sigma));
+export function findNearestKeyFrameTime({ frames, time, direction }: { frames: Frame[], time: number, direction: number }) {
+  const keyframes = frames.filter((f) => f.keyframe && (direction > 0 ? f.time >= time : f.time <= time));
   if (keyframes.length === 0) return undefined;
   const nearestKeyFrame = sortBy(keyframes, (keyframe) => (direction > 0 ? keyframe.time - time : time - keyframe.time))[0];
   if (!nearestKeyFrame) return undefined;

src/renderer/src/hooks/useKeyframes.ts

@@ -42,7 +42,7 @@ function useKeyframes({ keyframesEnabled, filePath, commandedTime, videoStream,
     return map;
   }, [detectedFps, neighbouringKeyFrames]);
 
-  const findNearestKeyFrameTime = useCallback(({ time, direction }: { time: number, direction: number }) => ffmpegFindNearestKeyFrameTime({ frames: neighbouringKeyFrames, time, direction, fps: detectedFps }), [neighbouringKeyFrames, detectedFps]);
+  const findNearestKeyFrameTime = useCallback(({ time, direction }: { time: number, direction: number }) => ffmpegFindNearestKeyFrameTime({ frames: neighbouringKeyFrames, time, direction }), [neighbouringKeyFrames]);
 
   useEffect(() => setNeighbouringKeyFrames({}), [filePath, videoStream]);