Stop ghost extension clips and recover last-frame extract after an interrupt.

Only one Comfy finish path can save a clip, hide catalog entries whose MP4 is missing, and retry last-frame extract so a truncated file does not dump FFmpeg noise into the UI.

Co-authored-by: Cursor <cursoragent@cursor.com>

pages/index.vue

@@ -702,6 +702,7 @@ interface LibraryClip {
   seed: number
   hideThumbnail: boolean
   hasThumbnail?: boolean
+  hasVideo?: boolean
   createdAt: number
   cfg?: number
   fps?: number
@@ -950,7 +951,7 @@ const plannedChain = computed(() => {
   ]
 })
 
-const visibleClips = computed(() => clips.value.filter(clip => clip.folderId === browseFolderId.value))
+const visibleClips = computed(() => clips.value.filter(clip => clip.folderId === browseFolderId.value && clip.hasVideo !== false))
 const libraryGroups = computed(() => {
   const groups = new Map<string, LibraryClip[]>()
   for (const clip of visibleClips.value) {
@@ -974,9 +975,9 @@ function clipsIn(id: string) {
 }
 
 function clipFamilyKey(clip: LibraryClip) {
-  if (clip.familyId) return clip.familyId
   const base = String(clip.name || '').trim().replace(/\s+p\d+$/i, '')
   if (base) return `name:${clip.folderId}:${base.toLowerCase()}`
+  if (clip.familyId) return clip.familyId
   return `solo:${clip.id}`
 }
 
@@ -985,7 +986,7 @@ function sortClipParts(a: LibraryClip, b: LibraryClip) {
   if (durationDelta) return durationDelta
   const chainDelta = (b.chainIndex || 0) - (a.chainIndex || 0)
   if (chainDelta) return chainDelta
-  return b.createdAt - a.createdAt
+  return a.createdAt - b.createdAt
 }
 
 function formatClipDuration(value?: number) {

server/api/extend.post.ts

@@ -98,7 +98,7 @@ export default defineEventHandler(async (event) => {
     extendTmpDir: tmpDir,
     extendPart1Path: part1Path,
     extendSourceClipId: source.id,
-    familyId: crypto.randomUUID(),
+    familyId: source.familyId || crypto.randomUUID(),
     parentClipId: source.id,
     chainIndex: (source.chainIndex || 0) + 1
   }

server/api/generate.post.ts

@@ -403,7 +403,14 @@ async function runGeneration(
     assertJobActive(job)
 
     copyFileSync(currentPath, part1Path)
+    try {
       await extractLastFrame(part1Path, framePath)
+    } catch (error) {
+      const detail = error instanceof Error ? error.message : String(error)
+      throw new Error(detail.includes('last frame')
+        ? detail
+        : `Could not extract the last frame for the next extension: ${detail}`)
+    }
     const frame = readFileSync(framePath)
     job.library.extendPart1Path = part1Path
     job.library.prompt = ext.prompt

server/utils/ffmpeg.ts

@@ -63,18 +63,30 @@ export async function extractLastFrame(inputPath: string, outputPath: string) {
   if (!existsSync(inputPath)) {
     throw new Error('Source video is missing')
   }
-  await runFfmpeg([
-    '-y',
-    '-sseof', '-1',
-    '-i', inputPath,
-    '-update', '1',
-    '-frames:v', '1',
-    '-q:v', '1',
-    outputPath
-  ], 30000)
-  if (!existsSync(outputPath)) {
-    throw new Error('FFmpeg did not write the last frame')
+
+  const attempts: string[][] = []
+  try {
+    const duration = await probeDuration(inputPath)
+    const seek = Math.max(0, duration - 0.08)
+    attempts.push(['-y', '-ss', seek.toFixed(3), '-i', inputPath, '-frames:v', '1', '-an', '-q:v', '1', outputPath])
+  } catch {
+    // Truncated files often have no duration index; fall through to decode attempts.
   }
+  attempts.push(
+    ['-y', '-sseof', '-0.04', '-i', inputPath, '-update', '1', '-frames:v', '1', '-an', '-q:v', '1', outputPath],
+    ['-y', '-i', inputPath, '-update', '1', '-an', '-q:v', '1', outputPath]
+  )
+
+  for (const args of attempts) {
+    try {
+      await runFfmpeg(args, 60000)
+      if (existsSync(outputPath)) return
+    } catch {
+      // Try the next seek strategy.
+    }
+  }
+
+  throw new Error('Could not extract the last frame. The video looks incomplete — interrupting Comfy mid-encode usually causes this. Earlier saved parts are still in the library.')
 }
 
 export async function probeHasAudio(filePath: string) {

server/utils/jobs.ts

@@ -78,6 +78,8 @@ export interface Job {
   }
   error?: string
   socketReady?: boolean
+  saving?: boolean
+  savedPromptId?: string
   segmentBuffer?: Buffer
   events: JobEvent[]
   listeners: Set<(event: JobEvent) => void>

server/utils/library.ts

@@ -317,7 +317,8 @@ export function publicLibrary(event: H3Event) {
     clips: catalog.clips.filter(clip => unlockedIds.has(clip.folderId)).map(clip => ({
       ...clip,
       name: clipTitle(clip),
-      hasThumbnail: !clip.hideThumbnail && existsSync(clipThumbPath(owner, clip.id))
+      hasThumbnail: !clip.hideThumbnail && existsSync(clipThumbPath(owner, clip.id)),
+      hasVideo: existsSync(clipVideoPath(owner, clip.id))
     })),
     stills: catalog.stills.filter(still => unlockedIds.has(still.folderId)),
     drafts: catalog.drafts

server/utils/pending.ts

@@ -70,10 +70,42 @@ export function deletePendingJob(jobId: string) {
 }
 
 export async function completePendingIfReady(pending: PendingJob) {
+  const alreadySaved = () => {
+    const live = getJob(pending.jobId)
+    if (live?.savedPromptId === pending.promptId) {
+      deletePendingJob(pending.jobId)
+      return {
+        type: 'complete' as const,
+        status: 'complete' as const,
+        message: pending.folderLocked
+          ? 'Saved to the locked folder. Unlock it to view.'
+          : (pending.extendPart1Path ? 'Extended video ready' : 'Video ready'),
+        progress: 100,
+        jobId: pending.jobId,
+        clipId: live.clipId,
+        hideThumbnail: pending.hideThumbnail,
+        folderLocked: pending.folderLocked
+      }
+    }
+    return null
+  }
+  const inFlight = () => {
+    const current = getJob(pending.jobId)
+    return Boolean(current && current.promptId === pending.promptId && current.saving)
+  }
+  if (inFlight()) return null
+  const saved = alreadySaved()
+  if (saved) return saved
   const history = await fetchHistory(pending.promptId)
+  if (inFlight()) return null
+  const afterHistory = alreadySaved()
+  if (afterHistory) return afterHistory
   const video = extractVideo(history, pending.promptId)
   if (!video) return null
   let buffer = await downloadComfyVideo(video)
+  if (inFlight()) return null
+  const afterDownload = alreadySaved()
+  if (afterDownload) return afterDownload
   if (pending.extendPart1Path && pending.extendTmpDir) {
     if (!existsSync(pending.extendPart1Path)) {
       removeExtendTemp(pending.extendTmpDir)
@@ -91,6 +123,8 @@ export async function completePendingIfReady(pending: PendingJob) {
     }
     removeExtendTemp(pending.extendTmpDir)
   }
+  const afterStitch = alreadySaved()
+  if (afterStitch) return afterStitch
   const clip = await saveClip({
     ownerKey: pending.ownerKey,
     folderId: pending.folderId,

server/utils/watch.ts

@@ -71,8 +71,10 @@ export function emitChainJob(job: Job, event: JobEvent, samplePct?: number) {
 export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Promise<void> {
   const persist = options.persist !== false
   job.socketReady = false
+  job.saving = false
   const ws = new WebSocket(comfyWsUrl(job.clientId))
   let settled = false
+  let finishing = false
   let pollTimer: ReturnType<typeof setInterval> | null = null
   let timeout: ReturnType<typeof setTimeout> | null = null
 
@@ -111,7 +113,7 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
       }
       const idleLeft = IDLE_MS - (Date.now() - lastActivity)
       timeout = setTimeout(() => {
-        if (settled) return
+        if (settled || finishing) return
         if (Date.now() - lastActivity >= IDLE_MS) {
           void fail('Timed out waiting for ComfyUI progress (30 minutes with no updates). The desktop job may still be running.')
           return
@@ -121,7 +123,7 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
     }
 
     const fail = async (error: string) => {
-      if (settled) return
+      if (settled || finishing) return
       settled = true
       cleanup()
       job.status = job.status === 'cancelled' ? 'cancelled' : 'error'
@@ -133,10 +135,18 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
     }
 
     const succeed = async () => {
-      if (settled || !job.promptId) return false
+      if (settled || finishing || !job.promptId) return false
+      finishing = true
+      job.saving = true
+      try {
         const history = await fetchHistory(job.promptId)
         const video = extractVideo(history, job.promptId)
-      if (!video) return false
+        if (!video) {
+          finishing = false
+          job.saving = false
+          return false
+        }
+        if (settled) return false
         settled = true
         cleanup()
         try {
@@ -184,6 +194,7 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
               chainIndex: job.library.chainIndex
             })
             job.clipId = clip.id
+            job.savedPromptId = job.promptId
             job.hideThumbnail = clip.hideThumbnail
             job.library.thumb = undefined
             job.library.name = nextClipPartName(clip.name)
@@ -197,6 +208,7 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
             if (!persist) {
               job.segmentBuffer = buffer
               deletePendingJob(job.id)
+              job.saving = false
               emitLocal({
                 type: 'checkpoint',
                 message: stitching ? 'Extension checkpoint saved' : 'Initial segment saved',
@@ -229,7 +241,9 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
             chainLabel: job.library?.chainLabel
           })
           deletePendingJob(job.id)
+          job.saving = false
         } catch (saveError) {
+          job.saving = false
           removeExtendTemp(job.library?.extendTmpDir)
           const message = saveError instanceof Error ? saveError.message : String(saveError)
           job.status = 'error'
@@ -240,12 +254,17 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
         }
         resolve()
         return true
+      } catch (error) {
+        finishing = false
+        job.saving = false
+        throw error
+      }
     }
 
     let dropMisses = 0
 
     const pollHistory = async () => {
-      if (settled || !job.promptId) return
+      if (settled || finishing || !job.promptId) return
       try {
         const inspected = inspectHistory(await fetchHistory(job.promptId), job.promptId)
         if (inspected.error) {
@@ -282,7 +301,7 @@ export function watchComfyJob(job: Job, options: { persist?: boolean } = {}): Pr
     })
 
     ws.addEventListener('close', () => {
-      if (settled || !job.promptId) return
+      if (settled || finishing || !job.promptId) return
       void pollHistory()
     })