diff --git a/.env_example b/.env_example
index 10474cf..fb6cb1b 100644
--- a/.env_example
+++ b/.env_example
@@ -14,6 +14,12 @@ ADMIN_PASSWORD=CHANGE_ME
 # Photo storage
 PHOTO_STORAGE_DIR=/opt/punimtag/data/uploads
 
+# Pending viewer uploads (same value as viewer UPLOAD_DIR when using that feature).
+# Web transcode cache defaults to a sibling folder: <parent>/web_videos next to
+# .../pending-photos (override with WEB_VIDEO_CACHE_DIR if needed).
+# UPLOAD_DIR=/mnt/db-server-uploads/pending-photos
+# WEB_VIDEO_CACHE_DIR=/mnt/db-server-uploads/web_videos
+
 # Redis (RQ jobs)
 REDIS_URL=redis://127.0.0.1:6379/0
 
diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index 5767c8b..3c3d04b 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -735,7 +735,7 @@ jobs:
           npm run build
         continue-on-error: true
         env:
-          VITE_API_URL: http://localhost:8000
+          VITE_API_URL: ''
 
       - name: Install viewer-frontend dependencies
         run: |
diff --git a/.gitignore b/.gitignore
index 66ca02d..2816edf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,9 +10,10 @@ dist/
 downloads/
 eggs/
 .eggs/
-# Python lib directories (but not viewer-frontend/lib/)
+# Python lib directories (but not viewer-frontend/lib/ or admin-frontend TS lib/)
 lib/
 !viewer-frontend/lib/
+!admin-frontend/src/lib/
 lib64/
 parts/
 sdist/
@@ -83,3 +84,4 @@ data/thumbnails/
 
 # PM2 ecosystem config (server-specific paths)
 ecosystem.config.js
+data/web_videos/
diff --git a/admin-frontend/.env_example b/admin-frontend/.env_example
index e9e5bd3..790cbb9 100644
--- a/admin-frontend/.env_example
+++ b/admin-frontend/.env_example
@@ -1,8 +1,14 @@
 # Admin frontend env (copy to ".env" )
 
-# Backend API base URL (must be reachable from the browser)
+# Backend API origin as seen by the browser. Leave empty for local dev: Vite proxies
+# /api to http://127.0.0.1:8000 (see vite.config.ts).
+# Production (same host as admin, proxy at /punim-api/): VITE_API_URL=/punim-api
 VITE_API_URL=
 
+# Production subpath for static assets (Vite base + React Router basename).
+# Local dev: leave unset (served at http://localhost:3000/).
+# VITE_BASE_PATH=/punim-admin
+
 # Enable developer mode (shows additional debug info and options)
 # Set to "true" to enable, leave empty or unset to disable
 VITE_DEVELOPER_MODE=
diff --git a/admin-frontend/public/logo.svg b/admin-frontend/public/logo.svg
new file mode 100644
index 0000000..28090da
Binary files /dev/null and b/admin-frontend/public/logo.svg differ
diff --git a/admin-frontend/src/App.tsx b/admin-frontend/src/App.tsx
index 04f7c28..b1d4094 100644
--- a/admin-frontend/src/App.tsx
+++ b/admin-frontend/src/App.tsx
@@ -171,7 +171,11 @@ function App() {
   return (
     <AuthProvider>
       <DeveloperModeProvider>
-        <BrowserRouter>
+        <BrowserRouter
+          basename={
+            import.meta.env.BASE_URL.replace(/\/$/, '') || undefined
+          }
+        >
           <AppRoutes />
         </BrowserRouter>
       </DeveloperModeProvider>
diff --git a/admin-frontend/src/api/client.ts b/admin-frontend/src/api/client.ts
index fb6729d..2553715 100644
--- a/admin-frontend/src/api/client.ts
+++ b/admin-frontend/src/api/client.ts
@@ -1,9 +1,7 @@
 import axios from 'axios'
 
-// Get API base URL from environment variable or use default
-// The .env file should contain: VITE_API_URL=http://127.0.0.1:8000
-// Alternatively, Vite proxy can be used (configured in vite.config.ts) by setting VITE_API_URL to empty string
-// When VITE_API_URL is empty/undefined, use relative path to work with HTTPS proxy
+// API origin as seen by the browser. For local dev, leave VITE_API_URL unset/empty so
+// requests use relative /api/v1/... and Vite proxies /api → http://127.0.0.1:8000.
 const envApiUrl = import.meta.env.VITE_API_URL
 const API_BASE_URL = envApiUrl && envApiUrl.trim() !== '' 
   ? envApiUrl 
diff --git a/admin-frontend/src/api/videos.ts b/admin-frontend/src/api/videos.ts
index 45fdc73..3ad7bdc 100644
--- a/admin-frontend/src/api/videos.ts
+++ b/admin-frontend/src/api/videos.ts
@@ -1,4 +1,5 @@
 import apiClient from './client'
+import { fastApiV1Path } from '../lib/fastapi-path'
 
 export interface PersonInfo {
   id: number
@@ -65,6 +66,21 @@ export interface RemoveVideoPersonResponse {
   message: string
 }
 
+export interface WebPlaybackPrepareResponse {
+  status: string
+  message: string
+}
+
+export interface WebPlaybackStatusResponse {
+  status: string
+  error?: string | null
+}
+
+function apiBasePath(): string {
+  const envApiUrl = import.meta.env.VITE_API_URL
+  return envApiUrl && envApiUrl.trim() !== '' ? envApiUrl : ''
+}
+
 export const videosApi = {
   listVideos: async (params: {
     page?: number
@@ -77,12 +93,14 @@ export const videosApi = {
     sort_by?: string
     sort_dir?: string
   }): Promise<ListVideosResponse> => {
-    const res = await apiClient.get<ListVideosResponse>('/api/v1/videos', { params })
+    const res = await apiClient.get<ListVideosResponse>(fastApiV1Path('/videos'), { params })
     return res.data
   },
 
   getVideoPeople: async (videoId: number): Promise<VideoPeopleResponse> => {
-    const res = await apiClient.get<VideoPeopleResponse>(`/api/v1/videos/${videoId}/people`)
+    const res = await apiClient.get<VideoPeopleResponse>(
+      fastApiV1Path(`/videos/${videoId}/people`)
+    )
     return res.data
   },
 
@@ -91,7 +109,7 @@ export const videosApi = {
     request: IdentifyVideoRequest
   ): Promise<IdentifyVideoResponse> => {
     const res = await apiClient.post<IdentifyVideoResponse>(
-      `/api/v1/videos/${videoId}/identify`,
+      fastApiV1Path(`/videos/${videoId}/identify`),
       request
     )
     return res.data
@@ -102,25 +120,42 @@ export const videosApi = {
     personId: number
   ): Promise<RemoveVideoPersonResponse> => {
     const res = await apiClient.delete<RemoveVideoPersonResponse>(
-      `/api/v1/videos/${videoId}/people/${personId}`
+      fastApiV1Path(`/videos/${videoId}/people/${personId}`)
     )
     return res.data
   },
 
   getThumbnailUrl: (videoId: number): string => {
-    const envApiUrl = import.meta.env.VITE_API_URL
-    const baseURL = envApiUrl && envApiUrl.trim() !== ''
-      ? envApiUrl
-      : '' // Use relative path when empty - works with proxy and HTTPS
-    return `${baseURL}/api/v1/videos/${videoId}/thumbnail`
+    const baseURL = apiBasePath()
+    return `${baseURL}${fastApiV1Path(`/videos/${videoId}/thumbnail`)}`
   },
 
   getVideoUrl: (videoId: number): string => {
-    const envApiUrl = import.meta.env.VITE_API_URL
-    const baseURL = envApiUrl && envApiUrl.trim() !== ''
-      ? envApiUrl
-      : '' // Use relative path when empty - works with proxy and HTTPS
-    return `${baseURL}/api/v1/videos/${videoId}/video`
+    const baseURL = apiBasePath()
+    return `${baseURL}${fastApiV1Path(`/videos/${videoId}/video`)}`
+  },
+
+  getWebPlaybackStreamUrl: (videoId: number): string => {
+    const baseURL = apiBasePath()
+    return `${baseURL}${fastApiV1Path(`/videos/${videoId}/web-playback/stream`)}`
+  },
+
+  prepareWebPlayback: async (
+    videoId: number
+  ): Promise<WebPlaybackPrepareResponse> => {
+    const res = await apiClient.post<WebPlaybackPrepareResponse>(
+      fastApiV1Path(`/videos/${videoId}/web-playback/prepare`)
+    )
+    return res.data
+  },
+
+  getWebPlaybackStatus: async (
+    videoId: number
+  ): Promise<WebPlaybackStatusResponse> => {
+    const res = await apiClient.get<WebPlaybackStatusResponse>(
+      fastApiV1Path(`/videos/${videoId}/web-playback/status`)
+    )
+    return res.data
   },
 }
 
diff --git a/admin-frontend/src/components/PhotoViewer.tsx b/admin-frontend/src/components/PhotoViewer.tsx
index 2b0df99..97d571b 100644
--- a/admin-frontend/src/components/PhotoViewer.tsx
+++ b/admin-frontend/src/components/PhotoViewer.tsx
@@ -2,6 +2,8 @@ import { useEffect, useState, useRef } from 'react'
 import { PhotoSearchResult, photosApi } from '../api/photos'
 import { apiClient } from '../api/client'
 import videosApi from '../api/videos'
+import { useWebPlaybackVideo } from '../hooks/useWebPlaybackVideo'
+import { isRemoteMediaPath } from '../lib/media-path'
 
 interface PhotoViewerProps {
   photos: PhotoSearchResult[]
@@ -52,13 +54,14 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
     return photo.media_type === 'video'
   }
 
-  // Get photo/video URL
-  const getPhotoUrl = (photoId: number, mediaType?: string) => {
-    if (mediaType === 'video') {
-      return videosApi.getVideoUrl(photoId)
-    }
-    return `${apiClient.defaults.baseURL}/api/v1/photos/${photoId}/image`
-  }
+  const currentIsVideo = currentPhoto ? isVideo(currentPhoto) : false
+  const webPlayback = useWebPlaybackVideo(
+    currentPhoto && currentIsVideo ? currentPhoto.id : null,
+    currentPhoto && currentIsVideo ? currentPhoto.path : ''
+  )
+
+  const getImageUrl = (photoId: number) =>
+    `${apiClient.defaults.baseURL}/api/v1/photos/${photoId}/image`
 
   // Preload adjacent images (skip videos)
   const preloadAdjacent = (index: number) => {
@@ -69,7 +72,7 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
         const nextPhotoId = nextPhoto.id
         if (!preloadedImages.current.has(nextPhotoId)) {
           const img = new Image()
-          img.src = getPhotoUrl(nextPhotoId, nextPhoto.media_type)
+          img.src = getImageUrl(nextPhotoId)
           preloadedImages.current.add(nextPhotoId)
         }
       }
@@ -81,7 +84,7 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
         const prevPhotoId = prevPhoto.id
         if (!preloadedImages.current.has(prevPhotoId)) {
           const img = new Image()
-          img.src = getPhotoUrl(prevPhotoId, prevPhoto.media_type)
+          img.src = getImageUrl(prevPhotoId)
           preloadedImages.current.add(prevPhotoId)
         }
       }
@@ -192,7 +195,9 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
   useEffect(() => {
     if (!currentPhoto) return
 
-    setImageLoading(true)
+    if (currentPhoto.media_type !== 'video') {
+      setImageLoading(true)
+    }
     setImageError(false)
     // Reset zoom when photo changes
     setZoom(1)
@@ -211,6 +216,52 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
     preloadAdjacent(currentIndex)
   }, [currentIndex, currentPhoto, photos.length])
 
+  // Sync loading / error for local web playback (videos)
+  useEffect(() => {
+    if (!currentPhoto || currentPhoto.media_type !== 'video') {
+      return
+    }
+    if (webPlayback.error) {
+      setImageError(true)
+      setImageLoading(false)
+      return
+    }
+    if (!webPlayback.videoSrc || webPlayback.preparing) {
+      setImageLoading(true)
+      setImageError(false)
+      return
+    }
+    setImageError(false)
+    setImageLoading(true)
+  }, [
+    currentPhoto?.id,
+    currentPhoto?.media_type,
+    webPlayback.error,
+    webPlayback.preparing,
+    webPlayback.videoSrc,
+  ])
+
+  // Prefetch browser-safe transcode for nearby local videos (viewer parity)
+  useEffect(() => {
+    if (photos.length === 0) {
+      return
+    }
+    const idxs = [
+      currentIndex - 2,
+      currentIndex - 1,
+      currentIndex + 1,
+      currentIndex + 2,
+    ].filter((i) => i >= 0 && i < photos.length)
+
+    for (const i of idxs) {
+      const p = photos[i]
+      if (!isVideo(p) || isRemoteMediaPath(p.path)) {
+        continue
+      }
+      videosApi.prepareWebPlayback(p.id).catch(() => {})
+    }
+  }, [currentIndex, photos])
+
   // Toggle favorite
   const toggleFavorite = async () => {
     if (loadingFavorite || !currentPhoto) return
@@ -273,8 +324,7 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
     return null
   }
 
-  const photoUrl = getPhotoUrl(currentPhoto.id, currentPhoto.media_type)
-  const currentIsVideo = isVideo(currentPhoto)
+  const imagePhotoUrl = getImageUrl(currentPhoto.id)
 
   return (
     <div className="fixed inset-0 bg-black z-[100] flex flex-col">
@@ -365,19 +415,22 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
         {imageError ? (
           <div className="text-white text-center">
             <div className="text-lg mb-2">Failed to load {currentIsVideo ? 'video' : 'image'}</div>
+            {webPlayback.error && (
+              <div className="text-sm text-red-300 mb-2">{webPlayback.error}</div>
+            )}
             <div className="text-sm text-gray-400">{currentPhoto.path}</div>
           </div>
         ) : currentIsVideo ? (
           <div className="relative h-full w-full max-h-[calc(90vh-80px)] max-w-full flex items-center justify-center">
             <video
               key={currentPhoto.id}
-              src={photoUrl}
+              src={webPlayback.videoSrc || undefined}
               className="object-contain w-full h-full max-w-full max-h-full"
               controls={true}
               controlsList="nodownload"
-              style={{ 
-                display: 'block', 
-                width: '100%', 
+              style={{
+                display: 'block',
+                width: '100%',
                 height: '100%',
                 maxWidth: '100%',
                 maxHeight: '100%',
@@ -399,7 +452,7 @@ export default function PhotoViewer({ photos, initialIndex, onClose }: PhotoView
             }}
           >
             <img
-              src={photoUrl}
+              src={imagePhotoUrl}
               alt={currentPhoto.filename || `Photo ${currentIndex + 1}`}
               className="max-w-full max-h-full object-contain"
               style={{ userSelect: 'none', pointerEvents: 'none' }}
diff --git a/admin-frontend/src/components/WebPlaybackVideo.tsx b/admin-frontend/src/components/WebPlaybackVideo.tsx
new file mode 100644
index 0000000..fc70b0e
--- /dev/null
+++ b/admin-frontend/src/components/WebPlaybackVideo.tsx
@@ -0,0 +1,51 @@
+import { forwardRef, type VideoHTMLAttributes } from 'react'
+import { useWebPlaybackVideo } from '../hooks/useWebPlaybackVideo'
+
+export interface WebPlaybackVideoProps
+  extends Omit<VideoHTMLAttributes<HTMLVideoElement>, 'src'> {
+  videoId: number
+  /** Filesystem or remote URL from the photo/video record */
+  mediaPath: string
+}
+
+/**
+ * HTML5 video that uses browser-safe web playback for local files (H.264/AAC transcode)
+ * and direct URL for remote http(s) sources.
+ */
+export const WebPlaybackVideo = forwardRef<HTMLVideoElement, WebPlaybackVideoProps>(
+  function WebPlaybackVideo(
+    { videoId, mediaPath, className, onLoadedData, onError, ...rest },
+    ref
+  ) {
+    const { videoSrc, preparing, error } = useWebPlaybackVideo(videoId, mediaPath)
+
+    return (
+      <div className="relative w-full">
+        {error && (
+          <div className="mb-2 rounded bg-red-900/80 px-2 py-1 text-sm text-red-100">
+            {error}
+          </div>
+        )}
+        {preparing && !videoSrc && !error && (
+          <div className="absolute inset-0 z-10 flex items-center justify-center rounded bg-black/50 text-sm text-white">
+            Preparing video…
+          </div>
+        )}
+        <video
+          ref={ref}
+          src={videoSrc || undefined}
+          className={className}
+          onLoadedData={(e) => {
+            onLoadedData?.(e)
+          }}
+          onError={(e) => {
+            if (!error) {
+              onError?.(e)
+            }
+          }}
+          {...rest}
+        />
+      </div>
+    )
+  }
+)
diff --git a/admin-frontend/src/hooks/useWebPlaybackVideo.ts b/admin-frontend/src/hooks/useWebPlaybackVideo.ts
new file mode 100644
index 0000000..69d280e
--- /dev/null
+++ b/admin-frontend/src/hooks/useWebPlaybackVideo.ts
@@ -0,0 +1,107 @@
+import { useEffect, useState } from 'react'
+import videosApi from '../api/videos'
+import { isRemoteMediaPath } from '../lib/media-path'
+
+const POLL_MS = 1000
+const MAX_POLLS = 900
+
+function formatPrepareError(err: unknown): string {
+  if (err && typeof err === 'object' && 'response' in err) {
+    const r = (err as { response?: { data?: { detail?: string }; status?: number } })
+      .response
+    if (r?.data?.detail) {
+      return String(r.data.detail)
+    }
+    if (r?.status === 503) {
+      return 'Video prep unavailable (Redis or worker may be down).'
+    }
+  }
+  if (err instanceof Error) {
+    return err.message
+  }
+  return 'Video playback failed'
+}
+
+/**
+ * Resolve a URL for HTML5 video: remote paths use the URL as-is; local files use
+ * browser-safe transcoded stream after prepare + poll (same behavior as viewer).
+ */
+export function useWebPlaybackVideo(
+  videoId: number | null,
+  mediaPath: string
+): { videoSrc: string | null; preparing: boolean; error: string | null } {
+  const [videoSrc, setVideoSrc] = useState<string | null>(null)
+  const [preparing, setPreparing] = useState(false)
+  const [error, setError] = useState<string | null>(null)
+
+  useEffect(() => {
+    if (videoId === null) {
+      setVideoSrc(null)
+      setPreparing(false)
+      setError(null)
+      return
+    }
+
+    let cancelled = false
+
+    if (isRemoteMediaPath(mediaPath)) {
+      setVideoSrc(mediaPath)
+      setPreparing(false)
+      setError(null)
+      return () => {
+        cancelled = true
+      }
+    }
+
+    const playbackId = videoId
+
+    async function run(): Promise<void> {
+      const id = playbackId
+      setPreparing(true)
+      setError(null)
+      setVideoSrc(null)
+      try {
+        const prep = await videosApi.prepareWebPlayback(id)
+        if (cancelled) {
+          return
+        }
+        if (prep.status === 'ready') {
+          setVideoSrc(videosApi.getWebPlaybackStreamUrl(id))
+          setPreparing(false)
+          return
+        }
+        for (let attempt = 0; attempt < MAX_POLLS; attempt++) {
+          if (cancelled) {
+            return
+          }
+          await new Promise((r) => setTimeout(r, POLL_MS))
+          const st = await videosApi.getWebPlaybackStatus(id)
+          if (cancelled) {
+            return
+          }
+          if (st.status === 'ready') {
+            setVideoSrc(videosApi.getWebPlaybackStreamUrl(id))
+            setPreparing(false)
+            return
+          }
+          if (st.status === 'failed') {
+            throw new Error(st.error || 'Video transcode failed')
+          }
+        }
+        throw new Error('Video preparation timed out')
+      } catch (e) {
+        if (!cancelled) {
+          setError(formatPrepareError(e))
+          setPreparing(false)
+        }
+      }
+    }
+
+    void run()
+    return () => {
+      cancelled = true
+    }
+  }, [videoId, mediaPath])
+
+  return { videoSrc, preparing, error }
+}
diff --git a/admin-frontend/src/lib/fastapi-path.ts b/admin-frontend/src/lib/fastapi-path.ts
new file mode 100644
index 0000000..27dad77
--- /dev/null
+++ b/admin-frontend/src/lib/fastapi-path.ts
@@ -0,0 +1,7 @@
+/**
+ * Relative URL under FastAPI's versioned mount (backend uses prefix="/api/v1").
+ */
+export function fastApiV1Path(suffix: string): string {
+  const p = suffix.startsWith('/') ? suffix : `/${suffix}`
+  return `/api/v1${p}`
+}
diff --git a/admin-frontend/src/lib/media-path.ts b/admin-frontend/src/lib/media-path.ts
new file mode 100644
index 0000000..f3007d8
--- /dev/null
+++ b/admin-frontend/src/lib/media-path.ts
@@ -0,0 +1,5 @@
+/** True if the library path points at a remote URL (browser plays directly). */
+export function isRemoteMediaPath(path: string): boolean {
+  const t = path.trim().toLowerCase()
+  return t.startsWith('http://') || t.startsWith('https://')
+}
diff --git a/admin-frontend/src/pages/Identify.tsx b/admin-frontend/src/pages/Identify.tsx
index 72a92d0..140be10 100644
--- a/admin-frontend/src/pages/Identify.tsx
+++ b/admin-frontend/src/pages/Identify.tsx
@@ -5,6 +5,7 @@ import peopleApi, { Person } from '../api/people'
 import { apiClient } from '../api/client'
 import tagsApi, { TagResponse } from '../api/tags'
 import videosApi, { VideoListItem, VideoPersonInfo, IdentifyVideoRequest } from '../api/videos'
+import { WebPlaybackVideo } from '../components/WebPlaybackVideo'
 import { useDeveloperMode } from '../context/DeveloperModeContext'
 import { useAuth } from '../context/AuthContext'
 import pendingIdentificationsApi, {
@@ -1942,8 +1943,9 @@ export default function Identify() {
                     <h3 className="text-lg font-semibold text-gray-700 mb-2">
                       {selectedVideo.filename}
                     </h3>
-                    <video
-                      src={videosApi.getVideoUrl(selectedVideo.id)}
+                    <WebPlaybackVideo
+                      videoId={selectedVideo.id}
+                      mediaPath={selectedVideo.path}
                       controls
                       className="w-full max-h-64 rounded"
                     />
diff --git a/admin-frontend/src/pages/Modify.tsx b/admin-frontend/src/pages/Modify.tsx
index 1bf799d..5ed547c 100644
--- a/admin-frontend/src/pages/Modify.tsx
+++ b/admin-frontend/src/pages/Modify.tsx
@@ -2,6 +2,7 @@ import { useEffect, useState, useRef, useCallback } from 'react'
 import peopleApi, { PersonWithFaces, PersonFaceItem, PersonVideoItem, PersonUpdateRequest } from '../api/people'
 import facesApi from '../api/faces'
 import videosApi from '../api/videos'
+import { WebPlaybackVideo } from '../components/WebPlaybackVideo'
 import { apiClient } from '../api/client'
 
 interface EditDialogProps {
@@ -1145,14 +1146,13 @@ export default function Modify() {
                 ×
               </button>
             </div>
-            <video
-              src={videosApi.getVideoUrl(selectedVideoToPlay.id)}
+            <WebPlaybackVideo
+              videoId={selectedVideoToPlay.id}
+              mediaPath={selectedVideoToPlay.path}
               controls
               autoPlay
               className="w-full max-h-[80vh] rounded"
-            >
-              Your browser does not support the video tag.
-            </video>
+            />
             {selectedVideoToPlay.date_taken && (
               <div className="text-sm text-gray-300 mt-2">
                 Date taken: {new Date(selectedVideoToPlay.date_taken).toLocaleDateString()}
diff --git a/admin-frontend/src/pages/ReportedPhotos.tsx b/admin-frontend/src/pages/ReportedPhotos.tsx
index 49910ee..0f29d61 100644
--- a/admin-frontend/src/pages/ReportedPhotos.tsx
+++ b/admin-frontend/src/pages/ReportedPhotos.tsx
@@ -363,7 +363,7 @@ export default function ReportedPhotos() {
                                   onClick={() => {
                                     const isVideo = reported.photo_media_type === 'video'
                                     const url = isVideo
-                                      ? videosApi.getVideoUrl(reported.photo_id)
+                                      ? `/video/${reported.photo_id}`
                                       : `${apiClient.defaults.baseURL}/api/v1/photos/${reported.photo_id}/image`
                                     window.open(url, '_blank')
                                   }}
diff --git a/admin-frontend/src/pages/Search.tsx b/admin-frontend/src/pages/Search.tsx
index e2acd17..d48566d 100644
--- a/admin-frontend/src/pages/Search.tsx
+++ b/admin-frontend/src/pages/Search.tsx
@@ -309,7 +309,9 @@ export default function Search() {
     } catch (error: any) {
       console.error('Error searching photos:', error)
       const errorMessage = error.response?.data?.detail || error.message || 'Unknown error'
-      alert(`Error searching photos: ${errorMessage}\n\nPlease check:\n1. Backend API is running (http://127.0.0.1:8000)\n2. You are logged in\n3. Database connection is working`)
+      alert(
+        `Error searching photos: ${errorMessage}\n\nPlease check:\n1. Backend API is running\n2. You are logged in\n3. Database connection is working`
+      )
     } finally {
       setLoading(false)
     }
diff --git a/admin-frontend/src/pages/Tags.tsx b/admin-frontend/src/pages/Tags.tsx
index 2327155..98859a7 100644
--- a/admin-frontend/src/pages/Tags.tsx
+++ b/admin-frontend/src/pages/Tags.tsx
@@ -2,6 +2,7 @@ import React, { useState, useEffect, useMemo, useRef } from 'react'
 import tagsApi, { PhotoWithTagsItem, TagResponse } from '../api/tags'
 import { useDeveloperMode } from '../context/DeveloperModeContext'
 import { apiClient } from '../api/client'
+import videosApi from '../api/videos'
 
 type ViewMode = 'list' | 'icons' | 'compact'
 
@@ -754,10 +755,19 @@ export default function Tags() {
                         <td className="p-2">{photo.id}</td>
                         <td className="p-2">
                           <a
-                            href={`${apiClient.defaults.baseURL}/api/v1/photos/${photo.id}/image`}
+                            href={
+                              photo.media_type === 'video'
+                                ? `/video/${photo.id}`
+                                : `${apiClient.defaults.baseURL}/api/v1/photos/${photo.id}/image`
+                            }
                             target="_blank"
                             rel="noopener noreferrer"
                             className="text-blue-600 hover:underline"
+                            title={
+                              photo.media_type === 'video'
+                                ? 'Open video (browser-safe playback)'
+                                : 'Open full photo'
+                            }
                           >
                             {photo.filename}
                           </a>
@@ -872,7 +882,12 @@ export default function Tags() {
                 {folderStates[folder.folderPath] === true && (
                   <div className="grid grid-cols-2 sm:grid-cols-3 md:grid-cols-4 lg:grid-cols-5 xl:grid-cols-6 gap-4">
                     {folder.photos.map(photo => {
-                      const photoUrl = `${apiClient.defaults.baseURL}/api/v1/photos/${photo.id}/image`
+                      const isVideo = photo.media_type === 'video'
+                      const imageUrl = `${apiClient.defaults.baseURL}/api/v1/photos/${photo.id}/image`
+                      const thumbUrl = isVideo
+                        ? videosApi.getThumbnailUrl(photo.id)
+                        : imageUrl
+                      const openUrl = isVideo ? `/video/${photo.id}` : imageUrl
                       const isSelected = selectedPhotoIds.has(photo.id)
                       
                       return (
@@ -928,10 +943,13 @@ export default function Tags() {
                           {/* Thumbnail */}
                           <div className="w-full aspect-square bg-gray-100 overflow-hidden">
                             <img
-                              src={photoUrl}
+                              src={thumbUrl}
                               alt={photo.filename}
                               className="w-full h-full object-cover cursor-pointer"
-                              onClick={() => window.open(photoUrl, '_blank')}
+                              onClick={() => window.open(openUrl, '_blank')}
+                              title={
+                                isVideo ? 'Open video' : 'Open full photo'
+                              }
                               onError={(e) => {
                                 const target = e.target as HTMLImageElement
                                 target.src = 'data:image/svg+xml,%3Csvg xmlns="http://www.w3.org/2000/svg" width="150" height="150"%3E%3Crect fill="%23ddd" width="150" height="150"/%3E%3Ctext x="50%25" y="50%25" text-anchor="middle" dy=".3em" fill="%23999"%3ENo Image%3C/text%3E%3C/svg%3E'
diff --git a/admin-frontend/src/pages/UserTaggedPhotos.tsx b/admin-frontend/src/pages/UserTaggedPhotos.tsx
index 83fd100..ae47866 100644
--- a/admin-frontend/src/pages/UserTaggedPhotos.tsx
+++ b/admin-frontend/src/pages/UserTaggedPhotos.tsx
@@ -443,7 +443,7 @@ export default function UserTaggedPhotos() {
                             onClick={() => {
                               const isVideo = linkage.photo_media_type === 'video'
                               const url = isVideo
-                                ? videosApi.getVideoUrl(linkage.photo_id)
+                                ? `/video/${linkage.photo_id}`
                                 : `${apiClient.defaults.baseURL}/api/v1/photos/${linkage.photo_id}/image`
                               window.open(url, '_blank')
                             }}
diff --git a/admin-frontend/src/pages/VideoPlayer.tsx b/admin-frontend/src/pages/VideoPlayer.tsx
index 18d7249..4072e54 100644
--- a/admin-frontend/src/pages/VideoPlayer.tsx
+++ b/admin-frontend/src/pages/VideoPlayer.tsx
@@ -1,14 +1,45 @@
 import { useState, useRef, useEffect } from 'react'
 import { useParams } from 'react-router-dom'
-import videosApi from '../api/videos'
+import { photosApi } from '../api/photos'
+import { WebPlaybackVideo } from '../components/WebPlaybackVideo'
 
 export default function VideoPlayer() {
   const { id } = useParams<{ id: string }>()
-  const videoId = id ? parseInt(id, 10) : null
+  const parsed = id ? parseInt(id, 10) : NaN
+  const videoId = Number.isFinite(parsed) ? parsed : null
   const videoRef = useRef<HTMLVideoElement>(null)
   const [showPlayButton, setShowPlayButton] = useState(true)
+  const [mediaPath, setMediaPath] = useState<string | null>(null)
+  const [pathError, setPathError] = useState<string | null>(null)
 
-  const videoUrl = videoId ? videosApi.getVideoUrl(videoId) : ''
+  useEffect(() => {
+    if (videoId === null || Number.isNaN(videoId)) {
+      setMediaPath(null)
+      setPathError(null)
+      return
+    }
+    let cancelled = false
+    setMediaPath(null)
+    setPathError(null)
+    photosApi
+      .getPhoto(videoId)
+      .then((p) => {
+        if (!cancelled) {
+          setMediaPath(p.path)
+        }
+      })
+      .catch((e) => {
+        if (!cancelled) {
+          setPathError(
+            e?.response?.data?.detail || e?.message || 'Failed to load video'
+          )
+          setMediaPath('')
+        }
+      })
+    return () => {
+      cancelled = true
+    }
+  }, [videoId])
 
   const handlePlay = () => {
     if (videoRef.current) {
@@ -53,7 +84,7 @@ export default function VideoPlayer() {
     }
   }, [])
 
-  if (!videoId || !videoUrl) {
+  if (videoId === null || Number.isNaN(videoId)) {
     return (
       <div className="min-h-screen flex items-center justify-center bg-black">
         <div className="text-white text-xl">Video not found</div>
@@ -61,12 +92,29 @@ export default function VideoPlayer() {
     )
   }
 
+  if (pathError && mediaPath === '') {
+    return (
+      <div className="min-h-screen flex items-center justify-center bg-black p-4">
+        <div className="text-red-200 text-center max-w-lg">{pathError}</div>
+      </div>
+    )
+  }
+
+  if (mediaPath === null) {
+    return (
+      <div className="min-h-screen flex items-center justify-center bg-black">
+        <div className="text-white text-xl">Loading…</div>
+      </div>
+    )
+  }
+
   return (
     <div className="min-h-screen bg-black flex items-center justify-center p-4">
       <div className="relative w-full max-w-full" style={{ maxHeight: 'calc(100vh - 2rem)' }}>
-        <video
+        <WebPlaybackVideo
           ref={videoRef}
-          src={videoUrl}
+          videoId={videoId}
+          mediaPath={mediaPath}
           className="w-full h-auto max-h-[calc(100vh-2rem)] object-contain"
           controls={true}
           controlsList="nodownload"
diff --git a/admin-frontend/vite.config.ts b/admin-frontend/vite.config.ts
index 6a22b4a..69198fc 100644
--- a/admin-frontend/vite.config.ts
+++ b/admin-frontend/vite.config.ts
@@ -1,17 +1,29 @@
-import { defineConfig } from 'vite'
+import { defineConfig, loadEnv } from 'vite'
 import react from '@vitejs/plugin-react'
 
 // https://vitejs.dev/config/
-export default defineConfig({
-  plugins: [react()],
-  server: {
-    port: 3000,
-    proxy: {
-      '/api': {
-        target: 'http://127.0.0.1:8000',
-        changeOrigin: true,
+export default defineConfig(({ mode }) => {
+  const env = loadEnv(mode, process.cwd(), '')
+  const raw = (env.VITE_BASE_PATH || '').trim()
+  const base =
+    raw === ''
+      ? '/'
+      : raw.endsWith('/')
+        ? raw
+        : `${raw}/`
+
+  return {
+    base,
+    plugins: [react()],
+    server: {
+      port: 3000,
+      proxy: {
+        '/api': {
+          target: 'http://127.0.0.1:8000',
+          changeOrigin: true,
+        },
       },
     },
-  },
+  }
 })
 
diff --git a/backend/api/tags.py b/backend/api/tags.py
index 748dd4a..78e0653 100644
--- a/backend/api/tags.py
+++ b/backend/api/tags.py
@@ -183,6 +183,7 @@ def get_photos_with_tags_endpoint(db: Session = Depends(get_db)) -> PhotosWithTa
             unidentified_face_count=p['unidentified_face_count'],
             tags=p['tags'],
             people_names=p.get('people_names', ''),
+            media_type=p.get('media_type') or 'image',
         )
         for p in photos_data
     ]
diff --git a/backend/api/videos.py b/backend/api/videos.py
index a921dd8..fea0a0b 100644
--- a/backend/api/videos.py
+++ b/backend/api/videos.py
@@ -7,6 +7,8 @@ from typing import Annotated, Optional
 
 from fastapi import APIRouter, Depends, HTTPException, Query, Request, status
 from fastapi.responses import FileResponse, Response, StreamingResponse
+from redis import Redis
+from rq import Queue
 from sqlalchemy.orm import Session
 
 from backend.db.session import get_db
@@ -21,6 +23,8 @@ from backend.schemas.videos import (
     IdentifyVideoRequest,
     IdentifyVideoResponse,
     RemoveVideoPersonResponse,
+    WebPlaybackPrepareResponse,
+    WebPlaybackStatusResponse,
 )
 from backend.services.video_service import (
     list_videos_for_identification,
@@ -30,9 +34,19 @@ from backend.services.video_service import (
     get_video_people_count,
 )
 from backend.services.thumbnail_service import get_video_thumbnail_path
+from backend.services.web_video_service import (
+    expire_web_playable_if_stale,
+    get_web_playback_status_dict,
+    prepare_web_playback,
+    resolve_valid_playable_path,
+    stream_web_playable_file,
+)
 
 router = APIRouter(prefix="/videos", tags=["videos"])
 
+_redis_conn = Redis(host="localhost", port=6379, db=0, decode_responses=False)
+_video_web_queue = Queue(connection=_redis_conn)
+
 
 @router.get("", response_model=ListVideosResponse)
 def list_videos(
@@ -328,34 +342,18 @@ def get_video_file(
         media_type = "video/mp4"
     
     file_size = os.path.getsize(video.path)
-    # Get range header - Starlette normalizes headers to lowercase
     range_header = request.headers.get("range")
-    
-    # Debug: Write to file to verify code execution
-    try:
-        with open("/tmp/video_debug.log", "a") as f:
-            all_headers = {k: v for k, v in request.headers.items()}
-            f.write(f"Video {video_id}: range_header={range_header}, all_headers={all_headers}\n")
-            if hasattr(request, 'scope'):
-                scope_headers = request.scope.get("headers", [])
-                f.write(f"  scope headers: {scope_headers}\n")
-            f.flush()
-    except Exception as e:
-        with open("/tmp/video_debug.log", "a") as f:
-            f.write(f"Debug write error: {e}\n")
-            f.flush()
-    
-    # Also check request scope directly as fallback
-    if not range_header and hasattr(request, 'scope'):
+    if not range_header and hasattr(request, "scope"):
         scope_headers = request.scope.get("headers", [])
         for header_name, header_value in scope_headers:
             if header_name.lower() == b"range":
-                range_header = header_value.decode() if isinstance(header_value, bytes) else header_value
-                with open("/tmp/video_debug.log", "a") as f:
-                    f.write(f"  Found range in scope: {range_header}\n")
-                    f.flush()
+                range_header = (
+                    header_value.decode()
+                    if isinstance(header_value, bytes)
+                    else header_value
+                )
                 break
-    
+
     if range_header:
         try:
             # Parse range header: "bytes=start-end"
@@ -420,6 +418,83 @@ def get_video_file(
     return response
 
 
+@router.post(
+    "/{video_id}/web-playback/prepare",
+    response_model=WebPlaybackPrepareResponse,
+)
+def prepare_video_web_playback(
+    video_id: int,
+    db: Session = Depends(get_db),
+) -> WebPlaybackPrepareResponse:
+    """Queue browser-safe transcoding (deduped per video). Requires Redis + RQ worker."""
+    try:
+        _video_web_queue.connection.ping()
+    except Exception as exc:
+        raise HTTPException(
+            status_code=status.HTTP_503_SERVICE_UNAVAILABLE,
+            detail=f"Redis unavailable: {exc}",
+        ) from exc
+    data = prepare_web_playback(video_id, db, _video_web_queue)
+    if data.get("status") == "not_found":
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail=data.get("message", "Not found"),
+        )
+    db.commit()
+    return WebPlaybackPrepareResponse(
+        status=data["status"],
+        message=data.get("message", ""),
+    )
+
+
+@router.get(
+    "/{video_id}/web-playback/status",
+    response_model=WebPlaybackStatusResponse,
+)
+def get_video_web_playback_status(
+    video_id: int,
+    db: Session = Depends(get_db),
+) -> WebPlaybackStatusResponse:
+    """Poll transcoding readiness for web playback."""
+    data = get_web_playback_status_dict(video_id, db)
+    if data["status"] == "not_found":
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Video not found",
+        )
+    return WebPlaybackStatusResponse(
+        status=data["status"],
+        error=data.get("error"),
+    )
+
+
+@router.get("/{video_id}/web-playback/stream")
+def stream_video_web_playback(
+    video_id: int,
+    request: Request,
+    db: Session = Depends(get_db),
+):
+    """Stream browser-safe MP4 (after prepare + ready). Supports Range requests."""
+    video = (
+        db.query(Photo)
+        .filter(Photo.id == video_id, Photo.media_type == "video")
+        .first()
+    )
+    if not video:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail=f"Video {video_id} not found",
+        )
+    expire_web_playable_if_stale(video)
+    db.commit()
+    db.refresh(video)
+    playable = resolve_valid_playable_path(video)
+    if not playable:
+        raise HTTPException(
+            status_code=getattr(status, "HTTP_425_TOO_EARLY", 425),
+            detail="Playback not ready. Call POST .../web-playback/prepare and poll status.",
+        )
+    return stream_web_playable_file(playable, request)
 
 
 
diff --git a/backend/db/models.py b/backend/db/models.py
index 9376e00..aeab19a 100644
--- a/backend/db/models.py
+++ b/backend/db/models.py
@@ -42,6 +42,11 @@ class Photo(Base):
     processed = Column(Boolean, default=False, nullable=False, index=True)
     file_hash = Column(Text, nullable=True, index=True)  # Nullable to support existing photos without hashes
     media_type = Column(Text, default="image", nullable=False, index=True)  # "image" or "video"
+    # Browser-safe playback (H.264/AAC); see web_video_service / migrations.
+    web_playable_path = Column(Text, nullable=True)
+    web_transcode_status = Column(Text, default="none", nullable=False)
+    web_transcode_error = Column(Text, nullable=True)
+    web_transcode_job_id = Column(Text, nullable=True)
 
     faces = relationship("Face", back_populates="photo", cascade="all, delete-orphan")
     photo_tags = relationship(
diff --git a/backend/schemas/tags.py b/backend/schemas/tags.py
index 30c0a68..8575e0d 100644
--- a/backend/schemas/tags.py
+++ b/backend/schemas/tags.py
@@ -88,6 +88,7 @@ class PhotoWithTagsItem(BaseModel):
     unidentified_face_count: int  # Count of faces with person_id IS NULL
     tags: str  # Comma-separated tags string (matching desktop)
     people_names: str = ""  # Comma-separated people names string
+    media_type: str = "image"  # "image" or "video"
 
 
 class PhotosWithTagsResponse(BaseModel):
diff --git a/backend/schemas/videos.py b/backend/schemas/videos.py
index 50f142b..135838d 100644
--- a/backend/schemas/videos.py
+++ b/backend/schemas/videos.py
@@ -80,6 +80,20 @@ class IdentifyVideoResponse(BaseModel):
     message: str
 
 
+class WebPlaybackPrepareResponse(BaseModel):
+    """Response after requesting browser-safe playback preparation."""
+
+    status: str
+    message: str
+
+
+class WebPlaybackStatusResponse(BaseModel):
+    """Transcode / readiness status for web playback."""
+
+    status: str
+    error: Optional[str] = None
+
+
 class RemoveVideoPersonResponse(BaseModel):
     """Response for removing a person from a video."""
 
diff --git a/backend/services/tasks.py b/backend/services/tasks.py
index d376e20..edf91f6 100644
--- a/backend/services/tasks.py
+++ b/backend/services/tasks.py
@@ -345,3 +345,78 @@ def process_faces_task(
     finally:
         db.close()
 
+
+def transcode_video_for_web_task(photo_id: int) -> dict:
+    """Background job: build browser-safe MP4 (or mark original as ready if H.264/AAC)."""
+    import os
+    import traceback
+
+    from backend.db.models import Photo
+    from backend.db.session import SessionLocal
+    from backend.services.web_video_service import (
+        derived_mp4_path,
+        expire_web_playable_if_stale,
+        probe_browser_safe_video,
+        run_ffmpeg_web_transcode,
+        web_playback_is_ready,
+    )
+
+    db = SessionLocal()
+    try:
+        photo = (
+            db.query(Photo)
+            .filter(Photo.id == photo_id)
+            .with_for_update()
+            .first()
+        )
+        if not photo or photo.media_type != "video":
+            return {"ok": False, "error": "not_found"}
+
+        expire_web_playable_if_stale(photo)
+        if web_playback_is_ready(photo):
+            db.commit()
+            return {"ok": True, "skipped": True}
+
+        photo.web_transcode_status = "running"
+        photo.web_transcode_error = None
+        db.commit()
+
+        if not os.path.isfile(photo.path):
+            raise RuntimeError("Source video file not found on disk")
+
+        if probe_browser_safe_video(photo.path):
+            photo.web_playable_path = photo.path
+            photo.web_transcode_status = "ready"
+            photo.web_transcode_error = None
+            db.commit()
+            return {"ok": True, "native": True}
+
+        dst = derived_mp4_path(photo_id)
+        run_ffmpeg_web_transcode(photo.path, dst)
+        photo.web_playable_path = str(dst)
+        photo.web_transcode_status = "ready"
+        photo.web_transcode_error = None
+        db.commit()
+        return {"ok": True, "transcoded": True}
+    except Exception as e:
+        try:
+            db.rollback()
+        except Exception:
+            pass
+        try:
+            print(f"[Task] web transcode failed for photo {photo_id}: {e}")
+            traceback.print_exc()
+        except (BrokenPipeError, OSError):
+            pass
+        try:
+            photo = db.query(Photo).filter(Photo.id == photo_id).first()
+            if photo:
+                photo.web_transcode_status = "failed"
+                photo.web_transcode_error = str(e)[:2000]
+                db.commit()
+        except Exception:
+            pass
+        return {"ok": False, "error": str(e)}
+    finally:
+        db.close()
+
diff --git a/backend/services/web_video_service.py b/backend/services/web_video_service.py
new file mode 100644
index 0000000..bd6daf0
--- /dev/null
+++ b/backend/services/web_video_service.py
@@ -0,0 +1,292 @@
+"""Browser-safe video playback: transcode cache with TTL and ffprobe shortcuts."""
+
+from __future__ import annotations
+
+import json
+import os
+import subprocess
+import time
+from pathlib import Path
+from typing import Any, Optional
+
+from fastapi import Request
+from fastapi.responses import FileResponse, Response, StreamingResponse
+from sqlalchemy.orm import Session
+
+from backend.db.models import Photo
+from backend.settings import get_web_video_cache_directory
+
+# Transcoded files older than this are deleted and must be regenerated.
+WEB_PLAYBACK_TTL_SECONDS = 86400  # 24 hours
+
+
+def derived_mp4_path(photo_id: int) -> Path:
+    """Absolute path for cached transcoded MP4."""
+    return get_web_video_cache_directory() / f"{photo_id}.mp4"
+
+
+def _file_within_ttl(path: Path) -> bool:
+    if not path.is_file():
+        return False
+    age = time.time() - path.stat().st_mtime
+    return age < WEB_PLAYBACK_TTL_SECONDS
+
+
+def expire_web_playable_if_stale(photo: Photo) -> None:
+    """Drop derived cache row + file when past TTL (does not delete originals)."""
+    if photo.media_type != "video":
+        return
+    cached = photo.web_playable_path
+    if not cached:
+        return
+    if cached == photo.path:
+        if not os.path.isfile(photo.path):
+            photo.web_playable_path = None
+            photo.web_transcode_status = "none"
+            photo.web_transcode_error = None
+        return
+    p = Path(cached)
+    if not p.is_file():
+        photo.web_playable_path = None
+        photo.web_transcode_status = "none"
+        photo.web_transcode_error = None
+        return
+    if not _file_within_ttl(p):
+        try:
+            p.unlink(missing_ok=True)
+        except OSError:
+            pass
+        photo.web_playable_path = None
+        photo.web_transcode_status = "none"
+        photo.web_transcode_error = None
+
+
+def probe_browser_safe_video(video_path: str) -> bool:
+    """True if streams look playable in common HTML5 video (H.264 + yuv420p + AAC)."""
+    if not os.path.isfile(video_path):
+        return False
+    try:
+        out = subprocess.run(
+            [
+                "ffprobe",
+                "-v",
+                "error",
+                "-show_entries",
+                "stream=codec_type,codec_name,pix_fmt",
+                "-of",
+                "json",
+                video_path,
+            ],
+            capture_output=True,
+            text=True,
+            timeout=60,
+            check=False,
+        )
+        if out.returncode != 0:
+            return False
+        data: dict[str, Any] = json.loads(out.stdout or "{}")
+        streams = data.get("streams") or []
+        vcodec: Optional[str] = None
+        pix: Optional[str] = None
+        has_aac = False
+        has_audio = False
+        for s in streams:
+            if s.get("codec_type") == "video":
+                vcodec = (s.get("codec_name") or "").lower()
+                pix = (s.get("pix_fmt") or "").lower()
+            elif s.get("codec_type") == "audio":
+                has_audio = True
+                if (s.get("codec_name") or "").lower() in ("aac", "mp4a"):
+                    has_aac = True
+        if vcodec != "h264":
+            return False
+        if pix not in ("yuv420p", "yuvj420p"):
+            return False
+        if has_audio and not has_aac:
+            return False
+        return True
+    except (OSError, json.JSONDecodeError, subprocess.TimeoutExpired):
+        return False
+
+
+def run_ffmpeg_web_transcode(src: str, dst: Path) -> None:
+    """Transcode to H.264/AAC MP4 suitable for browsers."""
+    dst.parent.mkdir(parents=True, exist_ok=True)
+    cmd = [
+        "ffmpeg",
+        "-y",
+        "-i",
+        src,
+        "-map",
+        "0:v:0",
+        "-map",
+        "0:a:0?",
+        "-c:v",
+        "libx264",
+        "-pix_fmt",
+        "yuv420p",
+        "-crf",
+        "23",
+        "-preset",
+        "veryfast",
+        "-c:a",
+        "aac",
+        "-b:a",
+        "160k",
+        "-movflags",
+        "+faststart",
+        str(dst),
+    ]
+    proc = subprocess.run(
+        cmd,
+        capture_output=True,
+        text=True,
+        timeout=7200,
+    )
+    if proc.returncode != 0:
+        err = (proc.stderr or proc.stdout or "")[-2000:]
+        raise RuntimeError(f"ffmpeg failed (code {proc.returncode}): {err}")
+
+
+def resolve_valid_playable_path(photo: Photo) -> Optional[Path]:
+    """Return filesystem path to serve if ready and valid, else None."""
+    expire_web_playable_if_stale(photo)
+    p = photo.web_playable_path
+    if not p or photo.web_transcode_status != "ready":
+        return None
+    if p == photo.path:
+        path = Path(p)
+        return path if path.is_file() else None
+    path = Path(p).resolve()
+    try:
+        path.relative_to(get_web_video_cache_directory().resolve())
+    except ValueError:
+        return None
+    if path.is_file() and _file_within_ttl(path):
+        return path
+    return None
+
+
+def web_playback_is_ready(photo: Photo) -> bool:
+    return resolve_valid_playable_path(photo) is not None
+
+
+def _parse_range_header(range_header: str | None, file_size: int) -> Optional[tuple[int, int]]:
+    if not range_header:
+        return None
+    if not range_header.startswith("bytes="):
+        return None
+    range_part = range_header[6:]
+    parts = range_part.split("-", 1)
+    start_str = parts[0].strip()
+    end_str = parts[1].strip() if len(parts) > 1 else ""
+    try:
+        start = int(start_str) if start_str else 0
+        end = int(end_str) if end_str else file_size - 1
+    except ValueError:
+        return None
+    if start < 0 or end >= file_size or start > end:
+        return None
+    return start, end
+
+
+def stream_web_playable_file(video_path: Path, request: Request) -> Response | FileResponse:
+    """Range-capable streaming for MP4 (same behavior as legacy video endpoint)."""
+    file_size = video_path.stat().st_size
+    range_header = request.headers.get("range")
+    range_data = _parse_range_header(range_header, file_size)
+
+    media_type = "video/mp4"
+
+    if range_data:
+        start, end = range_data
+        chunk_size = end - start + 1
+
+        def generate_chunk():
+            with open(video_path, "rb") as handle:
+                handle.seek(start)
+                remaining = chunk_size
+                while remaining > 0:
+                    chunk = handle.read(min(8192, remaining))
+                    if not chunk:
+                        break
+                    yield chunk
+                    remaining -= len(chunk)
+
+        return StreamingResponse(
+            generate_chunk(),
+            status_code=206,
+            headers={
+                "Content-Range": f"bytes {start}-{end}/{file_size}",
+                "Accept-Ranges": "bytes",
+                "Content-Length": str(chunk_size),
+                "Content-Type": media_type,
+                "Content-Disposition": "inline",
+                "Cache-Control": f"public, max-age={WEB_PLAYBACK_TTL_SECONDS}",
+            },
+            media_type=media_type,
+        )
+
+    response = FileResponse(
+        str(video_path),
+        media_type=media_type,
+    )
+    response.headers["Content-Disposition"] = "inline"
+    response.headers["Accept-Ranges"] = "bytes"
+    response.headers["Cache-Control"] = f"public, max-age={WEB_PLAYBACK_TTL_SECONDS}"
+    return response
+
+
+def prepare_web_playback(photo_id: int, db: Session, queue) -> dict[str, str]:
+    """Enqueue or confirm web playback; caller must commit after."""
+    photo = (
+        db.query(Photo)
+        .filter(Photo.id == photo_id, Photo.media_type == "video")
+        .with_for_update()
+        .first()
+    )
+    if not photo:
+        return {"status": "not_found", "message": "Video not found"}
+    if not os.path.isfile(photo.path):
+        return {"status": "not_found", "message": "File missing on server"}
+
+    expire_web_playable_if_stale(photo)
+    db.flush()
+
+    if web_playback_is_ready(photo):
+        return {"status": "ready", "message": "Playback file available"}
+
+    if photo.web_transcode_status in ("queued", "running"):
+        return {"status": photo.web_transcode_status, "message": "Transcode in progress"}
+
+    if photo.web_transcode_status == "failed":
+        photo.web_transcode_status = "none"
+        photo.web_transcode_error = None
+        photo.web_transcode_job_id = None
+
+    job = queue.enqueue(
+        "backend.services.tasks.transcode_video_for_web_task",
+        photo_id,
+        job_timeout=7200,
+        result_ttl=120,
+    )
+    photo.web_transcode_status = "queued"
+    photo.web_transcode_job_id = job.get_id()
+    photo.web_transcode_error = None
+    return {"status": "queued", "message": "Transcode queued"}
+
+
+def get_web_playback_status_dict(photo_id: int, db: Session) -> dict[str, Optional[str]]:
+    photo = db.query(Photo).filter(Photo.id == photo_id).first()
+    if not photo or photo.media_type != "video":
+        return {"status": "not_found", "error": None}
+    expire_web_playable_if_stale(photo)
+    db.commit()
+    db.refresh(photo)
+
+    if web_playback_is_ready(photo):
+        return {"status": "ready", "error": None}
+    err = photo.web_transcode_error
+    if photo.web_transcode_status == "failed":
+        return {"status": "failed", "error": err}
+    return {"status": photo.web_transcode_status, "error": err}
diff --git a/backend/settings.py b/backend/settings.py
index f38f653..33ef308 100644
--- a/backend/settings.py
+++ b/backend/settings.py
@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import os
+from pathlib import Path
 
 APP_TITLE = "PunimTag Web API"
 APP_VERSION = "0.1.0"
@@ -11,3 +12,46 @@ APP_VERSION = "0.1.0"
 PHOTO_STORAGE_DIR = os.getenv("PHOTO_STORAGE_DIR", "data/uploads")
 
 
+def _project_root() -> Path:
+    """Repository root (parent of ``backend/``)."""
+    return Path(__file__).resolve().parent.parent
+
+
+def get_web_video_cache_directory() -> Path:
+    """Filesystem directory for browser-safe transcoded MP4 cache.
+
+    Resolution order:
+
+    1. ``WEB_VIDEO_CACHE_DIR`` if set (absolute or relative to project root).
+    2. Otherwise ``<parent of UPLOAD_DIR>/web_videos`` when ``UPLOAD_DIR`` or
+       ``PENDING_PHOTOS_DIR`` is set (same layout as ``.../pending-photos`` next to
+       ``.../web_videos``).
+    3. Otherwise ``<project>/data/web_videos`` for local dev when no upload dir
+       is configured on the API process.
+    """
+    explicit = (os.getenv("WEB_VIDEO_CACHE_DIR") or "").strip()
+    if explicit:
+        path = Path(explicit).expanduser()
+        if not path.is_absolute():
+            path = (_project_root() / path).resolve()
+        else:
+            path = path.resolve()
+        path.mkdir(parents=True, exist_ok=True)
+        return path
+
+    pending_raw = (os.getenv("UPLOAD_DIR") or os.getenv("PENDING_PHOTOS_DIR") or "").strip()
+    if pending_raw:
+        pending = Path(pending_raw).expanduser()
+        if not pending.is_absolute():
+            pending = (_project_root() / pending).resolve()
+        else:
+            pending = pending.resolve()
+        out = (pending.parent / "web_videos").resolve()
+        out.mkdir(parents=True, exist_ok=True)
+        return out
+
+    fallback = (_project_root() / "data" / "web_videos").resolve()
+    fallback.mkdir(parents=True, exist_ok=True)
+    return fallback
+
+
diff --git a/docs/DEPLOY_CPANEL_STEP_BY_STEP.md b/docs/DEPLOY_CPANEL_STEP_BY_STEP.md
index 78eab79..32e5432 100644
--- a/docs/DEPLOY_CPANEL_STEP_BY_STEP.md
+++ b/docs/DEPLOY_CPANEL_STEP_BY_STEP.md
@@ -1058,15 +1058,31 @@ pip install -r requirements.txt
 5. Restart: `pm2 restart punimtag-admin`
 
 **Viewer frontend 404 for assets or API routes:**
-1. Verify `assetPrefix: '/punim-viewer'` is set in `viewer-frontend/next.config.ts` (NOT `basePath` - proxy strips the path)
+1. Verify `assetPrefix: '/punim-viewer'` is set in `viewer-frontend/next.config.ts` (common when proxy strips the prefix)
 2. Check `NEXT_PUBLIC_API_URL=/punim-api` in `viewer-frontend/.env`
-3. Check `NEXTAUTH_URL=https://your-domain.com/punim-viewer` and `AUTH_URL=https://your-domain.com/punim-viewer` in `viewer-frontend/.env`
-4. **If proxy strips `/punim-viewer` before forwarding:**
-   - All client-side `fetch('/api/...')` calls must be updated to use `/punim-viewer/api/...`
-   - A helper function `getApiPath()` is available in `lib/api-path.ts` for this
-   - NextAuth routes (`/api/auth/session`) may need `basePath: '/punim-viewer'` in NextAuth config
-5. Clean rebuild: `cd ~/punimtag/viewer-frontend && rm -rf .next && npm run build`
-6. Restart: `pm2 restart punimtag-viewer`
+3. Ensure NextAuth URLs match your routing strategy:
+   - Recommended (prefix-aware): `NEXTAUTH_URL=https://your-domain.com/punim-viewer`
+   - If your hosting proxy forces auth at root: use `NEXTAUTH_URL=https://your-domain.com` and redirect `/api/auth/*` to `/punim-viewer/api/auth/*` via `.htaccess`
+4. If you see browser requests hitting domain root paths like `/_next/image`, `/_next/static`, or `/api/...` and you cannot use Apache proxy flags (`[P]`) in `.htaccess`,
+   add minimal rewrite rules to map root paths into `/punim-viewer/` (server-level proxy still handles the prefixed paths):
+
+```apache
+# Do not rewrite already-prefixed app paths
+RewriteRule ^punim-viewer/ - [L]
+RewriteRule ^punim-admin/ - [L]
+RewriteRule ^punim-api/ - [L]
+
+# Next.js assets/images when viewer is hosted under /punim-viewer
+RewriteRule ^_next/static/(.*)$ /punim-viewer/_next/static/$1 [L,QSA,NE]
+RewriteRule ^_next/image(.*)$ /punim-viewer/_next/image$1 [L,QSA,NE]
+
+# Next.js API routes when client code requests /api/... at domain root
+# Use 307 if you need a redirect visible to browser; otherwise use [L] for internal rewrite.
+RewriteRule ^api/(.*)$ /punim-viewer/api/$1 [R=307,L,NE,QSA]
+```
+
+5. Clean rebuild (viewer): `cd ~/punimtag/viewer-frontend && rm -rf .next && npm run build`
+6. Restart: `pm2 restart punimtag-viewer --update-env`
 
 **Note:** If your reverse proxy strips `/punim-viewer` before forwarding to Next.js, you have two options:
 - **Option A (Recommended):** Ask hosting provider to preserve `/punim-viewer` prefix when forwarding to Next.js (only strip for static file serving if needed)
@@ -1077,6 +1093,104 @@ pip install -r requirements.txt
 - Check that `VITE_API_URL` and `NEXT_PUBLIC_API_URL` match your reverse proxy path
 - Test API directly: `curl http://localhost:8000/api/v1/health`
 
+### Backend Won't Start: TensorFlow/Keras Error (DeepFace)
+
+If backend logs show:
+
+`ValueError: You have tensorflow ... and this requires tf-keras package`
+
+Install `tf-keras` into the backend virtualenv (no code changes required):
+
+```bash
+cd ~/punimtag
+source venv/bin/activate
+pip install -U tf-keras
+pm2 restart punimtag-api --update-env
+```
+
+Verify the backend is healthy (use GET, not HEAD):
+
+```bash
+curl -s -o /dev/null -w "%{http_code}\n" https://your-domain.com/punim-api/health
+```
+
+### Video Thumbnails Return 500/502 in Viewer
+
+Symptoms:
+- Viewer grid shows video tiles but thumbnail requests return 500/502
+- Backend endpoint `/api/v1/videos/<id>/thumbnail` returns 500
+
+Cause:
+- Video thumbnail generation requires **either** OpenCV (`cv2`) **or** `ffmpeg`.
+  On many cPanel servers, neither is installed by default.
+
+Checks:
+
+```bash
+which ffmpeg || echo "ffmpeg missing"
+python3 -c "import cv2; print('cv2 ok')" 2>/dev/null || echo "no cv2"
+```
+
+If you have sudo on AlmaLinux/Rocky/CentOS 8, install `ffmpeg` via RPM Fusion:
+
+```bash
+sudo dnf -y install dnf-plugins-core
+sudo dnf config-manager --set-enabled powertools || true
+sudo dnf -y install \
+  https://download1.rpmfusion.org/free/el/rpmfusion-free-release-8.noarch.rpm \
+  https://download1.rpmfusion.org/nonfree/el/rpmfusion-nonfree-release-8.noarch.rpm
+sudo dnf -y install ffmpeg
+```
+
+Then restart backend:
+
+```bash
+pm2 restart punimtag-api --update-env
+```
+
+Verify thumbnail endpoint (GET, not `-I`/HEAD):
+
+```bash
+curl -s -o /dev/null -w "%{http_code}\n" \
+  https://your-domain.com/punim-api/api/v1/videos/734/thumbnail
+```
+
+### Video Playback Notes (AVI / MP4 codecs)
+
+- `.avi` is commonly served as `video/x-msvideo`. Most browsers cannot decode AVI in HTML5 video.
+  Result: "No video with supported format and MIME type found".
+- Some `.mp4` files contain **MPEG-4 Part 2** video (`codec_name=mpeg4`) instead of H.264.
+  Result: audio plays but video is black in many browsers.
+
+For best compatibility, use MP4 with H.264 video + AAC audio.
+
+### On-demand web video transcoding (viewer)
+
+The viewer transcodes **local** video files to a browser-safe **H.264 + AAC MP4** on first play (RQ job on the backend). Output is cached on disk under `data/web_videos/` with a **24-hour TTL** (files older than 24 hours are removed and regenerated on next play). Videos that already probe as **H.264 + yuv420p + AAC** use the **original file** (no duplicate encode).
+
+**Database migration (main `punimtag` DB):**
+
+From the repo root (loads `.env`, normalizes `DATABASE_URL` for `psql`):
+
+```bash
+./scripts/run-psql-migration.sh migrations/add-photos-web-playback-columns.sql
+```
+
+Manual alternative: if `DATABASE_URL` uses SQLAlchemy’s `+psycopg2` or `+asyncpg`, strip that segment before passing to `psql`, e.g. `postgresql+psycopg2://…` → `postgresql://…`.
+
+**Requirements:**
+
+- **Redis + `punimtag-worker`** (same RQ `default` queue as face processing).
+- **`ffmpeg`** and **`ffprobe`** on the server (see FFmpeg install steps above).
+
+**API (FastAPI, also proxied by the viewer):**
+
+- `POST /api/v1/videos/{id}/web-playback/prepare` — enqueue / dedupe transcode.
+- `GET /api/v1/videos/{id}/web-playback/status` — `ready` | `queued` | `running` | `failed`.
+- `GET /api/v1/videos/{id}/web-playback/stream` — MP4 stream (Range supported).
+
+The viewer calls `/api/photos/{id}/web-playback/*` (Next.js proxies to the backend using `BACKEND_BASE_URL`). Remote URLs (`http`/`https` paths) still play **directly** without transcoding.
+
 ### PM2 Not Persisting After Reboot
 
 ```bash
diff --git a/migrations/add-photos-web-playback-columns.sql b/migrations/add-photos-web-playback-columns.sql
new file mode 100644
index 0000000..9d56779
--- /dev/null
+++ b/migrations/add-photos-web-playback-columns.sql
@@ -0,0 +1,10 @@
+-- Web-playback transcoding cache (H.264 MP4) with TTL enforced in application layer.
+-- Run against the main punimtag database (same DB as photos table).
+
+ALTER TABLE photos ADD COLUMN IF NOT EXISTS web_playable_path TEXT;
+ALTER TABLE photos ADD COLUMN IF NOT EXISTS web_transcode_status TEXT NOT NULL DEFAULT 'none';
+ALTER TABLE photos ADD COLUMN IF NOT EXISTS web_transcode_error TEXT;
+ALTER TABLE photos ADD COLUMN IF NOT EXISTS web_transcode_job_id TEXT;
+
+COMMENT ON COLUMN photos.web_playable_path IS 'Path to browser-safe MP4 or original path if already H.264/AAC-safe';
+COMMENT ON COLUMN photos.web_transcode_status IS 'none|queued|running|ready|failed';
diff --git a/scripts/install_backend_tf_keras.sh b/scripts/install_backend_tf_keras.sh
new file mode 100755
index 0000000..c2b218d
--- /dev/null
+++ b/scripts/install_backend_tf_keras.sh
@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+PROJECT_ROOT="${PROJECT_ROOT:-$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)}"
+
+cd "$PROJECT_ROOT"
+
+if [[ ! -d "venv" ]]; then
+  echo "ERROR: venv/ not found at $PROJECT_ROOT/venv" >&2
+  exit 1
+fi
+
+echo "Activating venv and installing tf-keras."
+source "venv/bin/activate"
+
+python -V
+pip -V
+pip install -U tf-keras
+
+echo
+echo "Installed. Restart backend if needed (example):"
+echo "  pm2 restart punimtag-api --update-env"
diff --git a/scripts/install_ffmpeg_el8_rpmfusion.sh b/scripts/install_ffmpeg_el8_rpmfusion.sh
new file mode 100755
index 0000000..46856ce
--- /dev/null
+++ b/scripts/install_ffmpeg_el8_rpmfusion.sh
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+echo "Installing ffmpeg on EL8 via RPM Fusion."
+echo "This script is intended for AlmaLinux/Rocky/CentOS 8 with sudo access."
+echo
+
+if ! command -v dnf >/dev/null 2>&1; then
+  echo "ERROR: dnf not found. This doesn't look like an EL8 system." >&2
+  exit 1
+fi
+
+echo "Enabling PowerTools (if available)."
+sudo dnf -y install dnf-plugins-core >/dev/null
+sudo dnf -y config-manager --set-enabled powertools || true
+sudo dnf -y config-manager --set-enabled PowerTools || true
+
+echo "Installing RPM Fusion repos (EL8)."
+sudo dnf -y install \
+  https://download1.rpmfusion.org/free/el/rpmfusion-free-release-8.noarch.rpm \
+  https://download1.rpmfusion.org/nonfree/el/rpmfusion-nonfree-release-8.noarch.rpm
+
+echo "Installing ffmpeg."
+sudo dnf -y install ffmpeg
+
+echo
+echo "Done. Verifying:"
+command -v ffmpeg
+ffmpeg -version | head -n 1
diff --git a/scripts/run-psql-migration.sh b/scripts/run-psql-migration.sh
new file mode 100755
index 0000000..26bc1bf
--- /dev/null
+++ b/scripts/run-psql-migration.sh
@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+# Run a SQL migration against the main DATABASE_URL from repo .env.
+#
+# Usage (from anywhere):
+#   ./scripts/run-psql-migration.sh migrations/add-photos-web-playback-columns.sql
+#
+# Strips SQLAlchemy driver suffixes (+psycopg2, +asyncpg) so psql accepts the URL.
+# For remote Postgres, set DATABASE_URL in .env to postgresql://user:pass@host:port/dbname
+
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+cd "$ROOT"
+
+if [[ ! -f .env ]]; then
+  echo "ERROR: .env not found at $ROOT/.env" >&2
+  exit 1
+fi
+
+set -a
+# shellcheck disable=SC1091
+source .env
+set +a
+
+if [[ -z "${DATABASE_URL:-}" ]]; then
+  echo "ERROR: DATABASE_URL is not set in .env" >&2
+  exit 1
+fi
+
+SQL_FILE="${1:?Usage: $0 path/to/migration.sql}"
+
+if [[ ! -f "$SQL_FILE" ]]; then
+  echo "ERROR: SQL file not found: $SQL_FILE" >&2
+  exit 1
+fi
+
+URL="$DATABASE_URL"
+URL="${URL//+psycopg2/}"
+URL="${URL//+asyncpg/}"
+
+exec psql "$URL" -f "$SQL_FILE"
diff --git a/viewer-frontend/.env_example b/viewer-frontend/.env_example
index 89f82ca..6c31389 100644
--- a/viewer-frontend/.env_example
+++ b/viewer-frontend/.env_example
@@ -4,6 +4,16 @@
 DATABASE_URL=postgresql://punimtag:CHANGE_ME@127.0.0.1:5432/punimtag
 DATABASE_URL_AUTH=postgresql://punimtag_auth:CHANGE_ME@127.0.0.1:5432/punimtag_auth
 
+# FastAPI mount URL for server-side proxies (thumbnails, web-playback)—no trailing slash.
+# Local: origin only (helper adds /api/v1/...).
+BACKEND_BASE_URL=http://127.0.0.1:8000
+# Production (public URL through your reverse proxy), e.g.:
+# BACKEND_BASE_URL=https://jrccphotos.org/punim-api
+# Same machine as Next: http://127.0.0.1:8000 is also valid.
+
+# Production subpath for the Next app (no trailing slash). Local: leave unset.
+# NEXT_BASE_PATH=/punim-viewer
+
 
 # NextAuth
 NEXTAUTH_URL=http://127.0.0.1:3001
diff --git a/viewer-frontend/app/HomePageContent.tsx b/viewer-frontend/app/HomePageContent.tsx
index 23c8bc6..544d702 100644
--- a/viewer-frontend/app/HomePageContent.tsx
+++ b/viewer-frontend/app/HomePageContent.tsx
@@ -618,31 +618,26 @@ export function HomePageContent({ initialPhotos, people, tags }: HomePageContent
 
   // Handle closing the modal
   const handleCloseModal = () => {
-    // Set flag to prevent useEffect from running
+    // Skip one modal effect run (avoids racing with stale params during close)
     isClosingModalRef.current = true;
-    
+
     // Clear modal state immediately (no reload, instant close)
     setModalPhoto(null);
     setModalPhotos([]);
     setModalIndex(0);
-    
-    // Update URL directly using history API to avoid triggering Next.js router effects
-    // This prevents any reload or re-fetch when closing
+
+    // Must use Next.js router so useSearchParams() updates. Raw history.replaceState
+    // leaves the router thinking ?photo=… is still active, so router.push for the same
+    // photo is a no-op and the modal never reopens.
     const params = new URLSearchParams(window.location.search);
     params.delete('photo');
     params.delete('photos');
     params.delete('index');
     params.delete('autoplay');
-    
+
     const newUrl = params.toString() ? `/?${params.toString()}` : '/';
-    // Use window.history directly to avoid Next.js router processing
-    window.history.replaceState(
-      { ...window.history.state, as: newUrl, url: newUrl },
-      '',
-      newUrl
-    );
-    
-    // Reset flag after a short delay to allow effects to see it
+    router.replace(newUrl, { scroll: false });
+
     setTimeout(() => {
       isClosingModalRef.current = false;
     }, 100);
diff --git a/viewer-frontend/app/api/photos/[id]/image/route.ts b/viewer-frontend/app/api/photos/[id]/image/route.ts
index e73e78e..c3db63a 100644
--- a/viewer-frontend/app/api/photos/[id]/image/route.ts
+++ b/viewer-frontend/app/api/photos/[id]/image/route.ts
@@ -1,4 +1,5 @@
 import { NextRequest, NextResponse } from 'next/server';
+import { fastApiV1Url } from '@/lib/server/fastapi-backend';
 import { prisma } from '@/lib/db';
 import { readFile } from 'fs/promises';
 import { createReadStream } from 'fs';
@@ -167,11 +168,9 @@ export async function GET(
 
     // Handle video thumbnail request
     if (thumbnail && mediaType === 'video') {
-      const backendBaseUrl = process.env.BACKEND_BASE_URL || 'http://127.0.0.1:8000';
-
       try {
         const backendResponse = await fetch(
-          `${backendBaseUrl}/api/v1/videos/${photoId}/thumbnail`,
+          fastApiV1Url(`/videos/${photoId}/thumbnail`),
           { headers: { Accept: 'image/*' } }
         );
 
diff --git a/viewer-frontend/app/api/photos/[id]/web-playback/prepare/route.ts b/viewer-frontend/app/api/photos/[id]/web-playback/prepare/route.ts
new file mode 100644
index 0000000..96c5881
--- /dev/null
+++ b/viewer-frontend/app/api/photos/[id]/web-playback/prepare/route.ts
@@ -0,0 +1,39 @@
+import { NextResponse } from 'next/server';
+
+import { fastApiV1Url } from '@/lib/server/fastapi-backend';
+
+export const dynamic = 'force-dynamic';
+
+/**
+ * Queue browser-safe transcoding for a video (backend RQ job, deduped per photo).
+ */
+export async function POST(
+  _request: Request,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const { id } = await params;
+  const photoId = parseInt(id, 10);
+  if (Number.isNaN(photoId)) {
+    return NextResponse.json({ error: 'Invalid photo ID' }, { status: 400 });
+  }
+
+  try {
+    const res = await fetch(
+      fastApiV1Url(`/videos/${photoId}/web-playback/prepare`),
+      { method: 'POST', cache: 'no-store' }
+    );
+    const data = await res.json().catch(() => ({}));
+    if (!res.ok) {
+      return NextResponse.json(
+        { error: (data as { detail?: string }).detail || res.statusText },
+        { status: res.status }
+      );
+    }
+    return NextResponse.json(data, {
+      headers: { 'Cache-Control': 'no-store, max-age=0' },
+    });
+  } catch (e) {
+    console.error('web-playback prepare proxy error:', e);
+    return NextResponse.json({ error: 'Backend unreachable' }, { status: 502 });
+  }
+}
diff --git a/viewer-frontend/app/api/photos/[id]/web-playback/route.ts b/viewer-frontend/app/api/photos/[id]/web-playback/route.ts
new file mode 100644
index 0000000..627d9d9
--- /dev/null
+++ b/viewer-frontend/app/api/photos/[id]/web-playback/route.ts
@@ -0,0 +1,59 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+import { fastApiV1Url } from '@/lib/server/fastapi-backend';
+
+export const dynamic = 'force-dynamic';
+
+/**
+ * Proxy browser-safe video stream from FastAPI (Range requests preserved).
+ */
+export async function GET(
+  request: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const { id } = await params;
+  const photoId = parseInt(id, 10);
+  if (Number.isNaN(photoId)) {
+    return new NextResponse('Invalid photo ID', { status: 400 });
+  }
+
+  const url = fastApiV1Url(`/videos/${photoId}/web-playback/stream`);
+
+  const headers = new Headers();
+  const range = request.headers.get('range');
+  if (range) {
+    headers.set('Range', range);
+  }
+
+  try {
+    const backendRes = await fetch(url, { headers, cache: 'no-store' });
+    const outHeaders = new Headers();
+    const pass = [
+      'content-type',
+      'content-length',
+      'content-range',
+      'accept-ranges',
+      'cache-control',
+    ];
+    for (const h of pass) {
+      const v = backendRes.headers.get(h);
+      if (v) {
+        outHeaders.set(h, v);
+      }
+    }
+    if (!backendRes.ok && backendRes.status !== 206) {
+      const text = await backendRes.text();
+      return new NextResponse(text || backendRes.statusText, {
+        status: backendRes.status,
+        headers: outHeaders,
+      });
+    }
+    return new NextResponse(backendRes.body, {
+      status: backendRes.status,
+      headers: outHeaders,
+    });
+  } catch (e) {
+    console.error('web-playback stream proxy error:', e);
+    return new NextResponse('Backend unreachable', { status: 502 });
+  }
+}
diff --git a/viewer-frontend/app/api/photos/[id]/web-playback/status/route.ts b/viewer-frontend/app/api/photos/[id]/web-playback/status/route.ts
new file mode 100644
index 0000000..b1d8962
--- /dev/null
+++ b/viewer-frontend/app/api/photos/[id]/web-playback/status/route.ts
@@ -0,0 +1,37 @@
+import { NextResponse } from 'next/server';
+
+import { fastApiV1Url } from '@/lib/server/fastapi-backend';
+
+/** Polling must never hit a cached backend response */
+export const dynamic = 'force-dynamic';
+
+export async function GET(
+  _request: Request,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const { id } = await params;
+  const photoId = parseInt(id, 10);
+  if (Number.isNaN(photoId)) {
+    return NextResponse.json({ error: 'Invalid photo ID' }, { status: 400 });
+  }
+
+  try {
+    const res = await fetch(
+      fastApiV1Url(`/videos/${photoId}/web-playback/status`),
+      { cache: 'no-store' }
+    );
+    const data = await res.json().catch(() => ({}));
+    if (!res.ok) {
+      return NextResponse.json(
+        { error: (data as { detail?: string }).detail || res.statusText },
+        { status: res.status }
+      );
+    }
+    return NextResponse.json(data, {
+      headers: { 'Cache-Control': 'no-store, max-age=0' },
+    });
+  } catch (e) {
+    console.error('web-playback status proxy error:', e);
+    return NextResponse.json({ error: 'Backend unreachable' }, { status: 502 });
+  }
+}
diff --git a/viewer-frontend/components/PhotoViewerClient.tsx b/viewer-frontend/components/PhotoViewerClient.tsx
index ed2d7e0..11d1791 100644
--- a/viewer-frontend/components/PhotoViewerClient.tsx
+++ b/viewer-frontend/components/PhotoViewerClient.tsx
@@ -17,7 +17,7 @@ import {
   DialogTitle,
 } from '@/components/ui/dialog';
 import { parseFaceLocation, isPointInFaceWithFit } from '@/lib/face-utils';
-import { isUrl, isVideo, getImageSrc, getVideoSrc } from '@/lib/photo-utils';
+import { isUrl, isVideo, getImageSrc, getVideoSrc, getWebPlaybackStreamUrl } from '@/lib/photo-utils';
 import { IdentifyFaceDialog } from '@/components/IdentifyFaceDialog';
 import { LoginDialog } from '@/components/LoginDialog';
 import { RegisterDialog } from '@/components/RegisterDialog';
@@ -137,6 +137,9 @@ export function PhotoViewerClient({
   const [currentPhoto, setCurrentPhoto] = useState<PhotoWithDetails>(normalizePhoto(initialPhoto));
   const [currentIdx, setCurrentIdx] = useState(currentIndex);
   const [imageLoading, setImageLoading] = useState(false);
+  /** Local-file videos: URL after web-playback transcode is ready */
+  const [webPlaybackSrc, setWebPlaybackSrc] = useState<string | null>(null);
+  const [webPlaybackError, setWebPlaybackError] = useState<string | null>(null);
   const [isPlaying, setIsPlaying] = useState(autoPlay);
   const [currentInterval, setCurrentInterval] = useState(slideInterval);
   const slideTimerRef = useRef<NodeJS.Timeout | null>(null);
@@ -262,9 +265,111 @@ export function PhotoViewerClient({
     });
   }, [currentPhoto.id, currentPhoto.faces]);
 
+  // Local videos: queue transcode and poll until browser-safe stream is ready
+  useEffect(() => {
+    let cancelled = false;
+    if (!isVideo(currentPhoto) || isUrl(currentPhoto.path)) {
+      setWebPlaybackSrc(null);
+      setWebPlaybackError(null);
+      setImageLoading(false);
+      return () => {
+        cancelled = true;
+      };
+    }
+
+    const photoId = currentPhoto.id;
+    setWebPlaybackSrc(null);
+    setWebPlaybackError(null);
+    setImageLoading(true);
+
+    const pollIntervalMs = 1000;
+    const maxAttempts = 900;
+
+    async function prepareAndPoll() {
+      try {
+        const prep = await fetch(`/api/photos/${photoId}/web-playback/prepare`, {
+          method: 'POST',
+        });
+        const prepBody = await prep.json().catch(() => ({}));
+        if (!prep.ok) {
+          throw new Error(
+            (prepBody as { error?: string; detail?: string }).error ||
+              (prepBody as { detail?: string }).detail ||
+              prep.statusText
+          );
+        }
+
+        for (let attempt = 0; attempt < maxAttempts; attempt++) {
+          if (cancelled) {
+            return;
+          }
+          const st = await fetch(`/api/photos/${photoId}/web-playback/status`);
+          const body = await st.json().catch(() => ({}));
+          const statusVal = (body as { status?: string }).status;
+          if (statusVal === 'ready') {
+            if (!cancelled) {
+              setWebPlaybackSrc(getWebPlaybackStreamUrl(currentPhoto));
+              setImageLoading(false);
+            }
+            return;
+          }
+          if (statusVal === 'failed') {
+            throw new Error(
+              (body as { error?: string }).error || 'Video transcode failed'
+            );
+          }
+          if (statusVal === 'not_found') {
+            throw new Error('Video not found');
+          }
+          await new Promise((r) => setTimeout(r, pollIntervalMs));
+        }
+        throw new Error('Video preparation timed out');
+      } catch (e) {
+        if (!cancelled) {
+          setWebPlaybackError(e instanceof Error ? e.message : 'Playback failed');
+          setImageLoading(false);
+        }
+      }
+    }
+
+    prepareAndPoll();
+    return () => {
+      cancelled = true;
+    };
+  }, [currentPhoto.id, currentPhoto.path, isVideo(currentPhoto)]);
+
+  // Prefetch transcode for neighboring videos (±2) in the strip
+  useEffect(() => {
+    if (allPhotos.length === 0) {
+      return;
+    }
+    const idxs = [
+      currentIdx - 2,
+      currentIdx - 1,
+      currentIdx + 1,
+      currentIdx + 2,
+    ].filter((i) => i >= 0 && i < allPhotos.length);
+
+    for (const i of idxs) {
+      const p = allPhotos[i];
+      if (!isVideo(p) || isUrl(p.path)) {
+        continue;
+      }
+      fetch(`/api/photos/${p.id}/web-playback/prepare`, { method: 'POST' }).catch(
+        () => {}
+      );
+    }
+  }, [currentIdx, allPhotos]);
+
   // Auto-play videos when navigated to (only once per photo)
   useEffect(() => {
-    if (isVideo(currentPhoto) && videoRef.current && videoAutoPlayAttemptedRef.current !== currentPhoto.id) {
+    if (!isVideo(currentPhoto)) {
+      return;
+    }
+    if (!isUrl(currentPhoto.path) && !webPlaybackSrc) {
+      return;
+    }
+    if (videoRef.current && videoAutoPlayAttemptedRef.current !== currentPhoto.id) {
       // Mark that we've attempted auto-play for this photo
       videoAutoPlayAttemptedRef.current = currentPhoto.id;
       // Ensure controls are enabled
@@ -282,7 +387,7 @@ export function PhotoViewerClient({
       }, 100);
       return () => clearTimeout(timer);
     }
-  }, [currentPhoto]);
+  }, [currentPhoto, webPlaybackSrc]);
 
   // Check report status when photo changes or session changes
   useEffect(() => {
@@ -1232,10 +1337,20 @@ export function PhotoViewerClient({
               justifyContent: 'center',
             }}
           >
+            {webPlaybackError && (
+              <div className="rounded-md bg-black/70 px-4 py-3 text-center text-sm text-white">
+                {webPlaybackError}
+              </div>
+            )}
+            {!webPlaybackError && (
             <video
               ref={videoRef}
               key={currentPhoto.id}
-              src={getVideoSrc(currentPhoto)}
+              src={
+                isUrl(currentPhoto.path)
+                  ? getVideoSrc(currentPhoto)
+                  : webPlaybackSrc || undefined
+              }
               className="object-contain w-full h-full"
               controls={true}
               controlsList="nodownload"
@@ -1259,6 +1374,12 @@ export function PhotoViewerClient({
               onPause={() => setIsVideoPlaying(false)}
               onEnded={() => setIsVideoPlaying(false)}
             />
+            )}
+            {!webPlaybackError && !isUrl(currentPhoto.path) && !webPlaybackSrc && (
+              <div className="absolute inset-0 flex items-center justify-center bg-black/40 text-white text-sm">
+                Preparing video for playback…
+              </div>
+            )}
           </div>
         ) : (
         <div
diff --git a/viewer-frontend/lib/photo-utils.ts b/viewer-frontend/lib/photo-utils.ts
index 41b3c08..f0f2f6c 100644
--- a/viewer-frontend/lib/photo-utils.ts
+++ b/viewer-frontend/lib/photo-utils.ts
@@ -57,3 +57,11 @@ export function getVideoSrc(photo: Photo): string {
   return `/api/photos/${photo.id}/image`;
 }
 
+/**
+ * Browser-safe transcoded MP4 URL (after prepare + status=ready).
+ */
+export function getWebPlaybackStreamUrl(photo: Photo): string {
+  return `/api/photos/${photo.id}/web-playback`;
+}
+
+
diff --git a/viewer-frontend/lib/server/fastapi-backend.ts b/viewer-frontend/lib/server/fastapi-backend.ts
new file mode 100644
index 0000000..60446da
--- /dev/null
+++ b/viewer-frontend/lib/server/fastapi-backend.ts
@@ -0,0 +1,34 @@
+/**
+ * FastAPI base URL for Next.js route handlers (server-side fetch only).
+ *
+ * Set BACKEND_BASE_URL to the **mount point** of FastAPI (no trailing slash).
+ * This helper appends `/api/v1` and the resource path. It matches how the
+ * browser sees versioned routes when the proxy maps `/punim-api/` → FastAPI root:
+ *
+ *   BACKEND_BASE_URL=https://jrccphotos.org/punim-api
+ *   fastApiV1Url(`/videos/5/web-playback/stream`)
+ *   → https://jrccphotos.org/punim-api/api/v1/videos/5/web-playback/stream
+ *
+ * On the same host as the API process you may use `http://127.0.0.1:8000` instead
+ * (still produces `.../api/v1/...` on port 8000). If BACKEND_BASE_URL already ends
+ * with `/api/v1`, it is not duplicated.
+ */
+
+function normalizeBackendBase(): string {
+  const raw = (process.env.BACKEND_BASE_URL || 'http://127.0.0.1:8000').trim();
+  return raw.replace(/\/+$/, '');
+}
+
+/**
+ * Full URL for a resource under FastAPI's /api/v1 prefix.
+ *
+ * @param resourcePath Path after /api/v1, e.g. `/videos/5/web-playback/stream`
+ */
+export function fastApiV1Url(resourcePath: string): string {
+  const base = normalizeBackendBase();
+  const path = resourcePath.startsWith('/') ? resourcePath : `/${resourcePath}`;
+  if (/\/api\/v1$/i.test(base)) {
+    return `${base}${path}`;
+  }
+  return `${base}/api/v1${path}`;
+}
diff --git a/viewer-frontend/next.config.ts b/viewer-frontend/next.config.ts
index 384a05f..dde6acc 100644
--- a/viewer-frontend/next.config.ts
+++ b/viewer-frontend/next.config.ts
@@ -1,6 +1,18 @@
 import type { NextConfig } from "next";
 
+/** Subpath deploy (e.g. /punim-viewer). Omit or empty for local dev at /. */
+function normalizeNextBasePath(raw: string): string {
+  const t = raw.trim().replace(/\/+$/, "");
+  if (!t) {
+    return "";
+  }
+  return t.startsWith("/") ? t : `/${t}`;
+}
+
+const nextBasePath = normalizeNextBasePath(process.env.NEXT_BASE_PATH || "");
+
 const nextConfig: NextConfig = {
+  ...(nextBasePath ? { basePath: nextBasePath } : {}),
   images: {
     // Configure remote patterns for external image sources (SharePoint, CDN, etc.)
     remotePatterns: [
diff --git a/viewer-frontend/scripts/install-dependencies.sh b/viewer-frontend/scripts/install-dependencies.sh
index ab64403..3579f19 100755
--- a/viewer-frontend/scripts/install-dependencies.sh
+++ b/viewer-frontend/scripts/install-dependencies.sh
@@ -66,6 +66,23 @@ if [ ${#MISSING_DEPS[@]} -gt 0 ]; then
                     sudo apt-get install -y ffmpeg
                 fi
             done
+        elif command -v dnf &> /dev/null; then
+            for dep in "${MISSING_DEPS[@]}"; do
+                if [ "$dep" = "ffmpeg" ]; then
+                    echo "Installing ffmpeg with dnf..."
+                    echo "Note: On EL8 (Alma/Rocky/CentOS), ffmpeg may require RPM Fusion repos."
+                    echo ""
+                    if sudo dnf -y install ffmpeg; then
+                        echo "✅ ffmpeg installed"
+                    else
+                        echo ""
+                        echo "⚠️  dnf couldn't find ffmpeg."
+                        echo "   If this is EL8, run the helper installer from the repo root:"
+                        echo "     sudo bash ../../scripts/install_ffmpeg_el8_rpmfusion.sh"
+                        echo ""
+                    fi
+                fi
+            done
         elif command -v brew &> /dev/null; then
             for dep in "${MISSING_DEPS[@]}"; do
                 if [ "$dep" = "libvips-dev" ]; then