feat: auto-captions

.gitignore

@@ -28,3 +28,5 @@ node_modules
 
 # cursor
 bun.lockb
+apps/transcription/__pycache__
+apps/transcription/env

apps/transcription/README.md

@@ -0,0 +1,86 @@
+Before you follow anything in this guide, please make sure you've followed the steps in the [README](../../README.md) (under "Optional: Auto-captions (Transcription) Setup").
+
+Open your terminal and make sure you're in the `apps/transcription` directory.
+
+1. Create virtual environment
+
+```bash
+python -m venv env
+```
+
+2. Activate it
+
+**Windows:**
+
+```bash
+env\Scripts\activate
+```
+
+**macOS/Linux:**
+
+```bash
+source env/bin/activate
+```
+
+> Note: if you're using VS Code/Cursor and you're seeing errors with the imports about the modules not being found,
+> You might have to press CTRL + Shift + P -> Python: Select Interpreter -> Enter interpreter path -> Find -> env -> scripts -> python.exe
+
+3. Install libraries/packages/whatever you wanna call them
+
+```bash
+pip install -r requirements.txt
+```
+
+4. Make sure you have a Modal account. If you don't: [create one](https://modal.com/)
+
+> If you don't know what Modal is: it allows us to process the actual audio and transcribe with Whisper by providing the infra to run Python code with a lot of RAM, generally affordable.
+
+5. Once you've got a Modal accoumt, run this:
+
+```bash
+python -m modal setup
+```
+
+It's gonna open a browser so you can authenticate.
+
+6. Test it if you want to make sure it actually works:
+
+```bash
+modal run transcription.py
+```
+
+6. Deploy the function!
+
+```bash
+modal deploy transcription.py
+```
+
+7. Set the required secrets in Modal
+
+So the script we just deployed interacts with Cloudflare to do two things:
+
+- Download the audio (so it can be transcribed with Whisper)
+- Delete the file after processing (privacy)
+
+To do those things, the script needs access to these environment variables:
+```bash
+CLOUDFLARE_ACCOUNT_ID=your-account-id
+R2_ACCESS_KEY_ID=your-access-key-id
+R2_SECRET_ACCESS_KEY=your-secret-access-key
+R2_BUCKET_NAME=opencut-transcription
+```
+
+Remember, we set these earlier in `.env.local`.
+
+So let's do it:
+
+   - Go to [Modal Secrets](https://modal.com/secrets/mazewinther/main)
+   - Click "Custom" and enter "opencut-r2-secrets" for the name.
+   - Now you can just click "Import .env" and copy/paste the 4 variables from your `.env.local` file. Copy and paste these only:
+      ```bash
+      CLOUDFLARE_ACCOUNT_ID=your-account-id
+      R2_ACCESS_KEY_ID=your-access-key-id
+      R2_SECRET_ACCESS_KEY=your-secret-access-key
+      R2_BUCKET_NAME=opencut-transcription
+      ```
+    - Click "Done" and you should see some cool particles!

apps/transcription/requirements.txt

@@ -0,0 +1,5 @@
+modal
+openai-whisper
+boto3
+pydantic
+cryptography

apps/transcription/transcription.py

@@ -0,0 +1,143 @@
+import modal
+from pydantic import BaseModel
+
+app = modal.App("opencut-transcription")
+
+class TranscribeRequest(BaseModel):
+    filename: str
+    language: str = "auto"
+    decryptionKey: str = None
+    iv: str = None
+
+@app.function(
+    image=modal.Image.debian_slim()
+        .apt_install(["ffmpeg"])
+        .pip_install(["openai-whisper", "boto3", "fastapi[standard]", "pydantic", "cryptography"]),
+    gpu="A10G",
+    timeout=300, # 5m
+    secrets=[modal.Secret.from_name("opencut-r2-secrets")]
+)
+@modal.fastapi_endpoint(method="POST")
+def transcribe_audio(request: TranscribeRequest):
+    import whisper
+    import boto3
+    import tempfile
+    import os
+    import json
+    
+    try:
+        filename = request.filename
+        language = request.language
+        decryption_key = request.decryptionKey
+        iv = request.iv
+        
+        if not filename:
+            return {
+                "error": "Missing filename parameter"
+            }
+        
+        # Initialize R2 client
+        s3_client = boto3.client(
+            's3',
+            endpoint_url=f'https://{os.environ["CLOUDFLARE_ACCOUNT_ID"]}.r2.cloudflarestorage.com',
+            aws_access_key_id=os.environ["R2_ACCESS_KEY_ID"],
+            aws_secret_access_key=os.environ["R2_SECRET_ACCESS_KEY"],
+            region_name='auto'
+        )
+        
+        # Create temporary file for audio
+        with tempfile.NamedTemporaryFile(delete=False, suffix='.wav') as temp_file:
+            temp_path = temp_file.name
+            
+            try:
+                # Download audio from R2
+                s3_client.download_file(
+                    os.environ["R2_BUCKET_NAME"], 
+                    filename, 
+                    temp_path
+                )
+                
+                # If decryption key provided, decrypt the file directly (zero-knowledge)
+                if decryption_key and iv:
+                    import base64
+                    from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
+                    from cryptography.hazmat.backends import default_backend
+                    
+                    # Read the encrypted file
+                    with open(temp_path, 'rb') as f:
+                        encrypted_data = f.read()
+                    
+                    # Decode the key and IV from base64
+                    key_bytes = base64.b64decode(decryption_key)
+                    iv_bytes = base64.b64decode(iv)
+                    
+                    # Decrypt the data using AES-GCM
+                    # Extract the tag (last 16 bytes) and ciphertext
+                    tag = encrypted_data[-16:]
+                    ciphertext = encrypted_data[:-16]
+                    
+                    cipher = Cipher(
+                        algorithms.AES(key_bytes),
+                        modes.GCM(iv_bytes, tag),
+                        backend=default_backend()
+                    )
+                    decryptor = cipher.decryptor()
+                    decrypted_data = decryptor.update(ciphertext) + decryptor.finalize()
+                    
+                    # Write decrypted audio back to temp file
+                    with open(temp_path, 'wb') as f:
+                        f.write(decrypted_data)
+                
+                # Load Whisper model
+                model = whisper.load_model("base")
+                
+                # Transcribe audio
+                if language == "auto":
+                    result = model.transcribe(temp_path)
+                else:
+                    result = model.transcribe(temp_path, language=language.lower())
+                
+                # Delete audio file from R2 (cleanup)
+                s3_client.delete_object(
+                    Bucket=os.environ["R2_BUCKET_NAME"],
+                    Key=filename
+                )
+                
+                # Adjust segment timing - Whisper is consistently late by ~500ms
+                adjusted_segments = []
+                for segment in result["segments"]:
+                    adjusted_segment = segment.copy()
+                    # Shift start/end times earlier by 500ms, don't go below 0
+                    adjusted_segment["start"] = max(0, segment["start"] - 0.5)
+                    adjusted_segment["end"] = max(0.5, segment["end"] - 0.5)  # Ensure duration is at least 0.5s
+                    adjusted_segments.append(adjusted_segment)
+                
+                return {
+                    "text": result["text"],
+                    "segments": adjusted_segments,
+                    "language": result["language"]
+                }
+                
+            finally:
+                # Clean up temporary file
+                if os.path.exists(temp_path):
+                    os.unlink(temp_path)
+                    
+    except Exception as e:
+        import traceback
+        print(f"Transcription error: {str(e)}")
+        print(f"Traceback: {traceback.format_exc()}")
+        
+        # Return error response that matches expected format
+        return {
+            "error": str(e),
+            "text": "",
+            "segments": [],
+            "language": "unknown"
+        }
+
+@app.local_entrypoint()
+def main():
+    # Test function - you can call this with modal run transcription.py
+    print("Transcription service is ready to deploy!")
+    print("Deploy with: modal deploy transcription.py")

apps/web/.env.example

@@ -21,3 +21,13 @@ NEXT_PUBLIC_MARBLE_API_URL=https://api.marblecms.com
 # Freesound (generate at https://freesound.org/apiv2/apply/)
 FREESOUND_CLIENT_ID=...
 FREESOUND_API_KEY=...
+
+# Cloudflare R2 (for auto-captions/transcription)
+# Get these from Cloudflare Dashboard > R2 > Manage R2 API tokens
+CLOUDFLARE_ACCOUNT_ID=your-account-id
+R2_ACCESS_KEY_ID=your-access-key-id
+R2_SECRET_ACCESS_KEY=your-secret-access-key
+R2_BUCKET_NAME=opencut-transcription
+
+# Modal transcription endpoint (from modal deploy transcription.py)
+MODAL_TRANSCRIPTION_URL=https://your-username--opencut-transcription-transcribe-audio.modal.run

apps/web/package.json

@@ -4,7 +4,7 @@
   "private": true,
   "packageManager": "bun@1.2.18",
   "scripts": {
-    "dev": "next dev",
+    "dev": "next dev --turbopack",
     "build": "next build",
     "start": "next start",
     "lint": "biome check src/",
@@ -29,6 +29,7 @@
     "@upstash/ratelimit": "^2.0.5",
     "@upstash/redis": "^1.35.0",
     "@vercel/analytics": "^1.4.1",
+    "aws4fetch": "^1.0.20",
     "better-auth": "^1.2.7",
     "botid": "^1.4.2",
     "class-variance-authority": "^0.7.1",
@@ -43,6 +44,7 @@
     "input-otp": "^1.4.1",
     "lucide-react": "^0.468.0",
     "motion": "^12.18.1",
+    "nanoid": "^5.1.5",
     "next": "^15.4.5",
     "next-themes": "^0.4.4",
     "pg": "^8.16.2",

apps/web/src/app/api/get-upload-url/route.ts

@@ -0,0 +1,128 @@
+import { NextRequest, NextResponse } from "next/server";
+import { z } from "zod";
+import { AwsClient } from "aws4fetch";
+import { nanoid } from "nanoid";
+import { env } from "@/env";
+import { baseRateLimit } from "@/lib/rate-limit";
+import { isTranscriptionConfigured } from "@/lib/transcription-utils";
+
+const uploadRequestSchema = z.object({
+  fileExtension: z.enum(["wav", "mp3", "m4a", "flac"], {
+    errorMap: () => ({
+      message: "File extension must be wav, mp3, m4a, or flac",
+    }),
+  }),
+});
+
+const apiResponseSchema = z.object({
+  uploadUrl: z.string().url(),
+  fileName: z.string().min(1),
+});
+
+export async function POST(request: NextRequest) {
+  try {
+    // Rate limiting
+    const ip = request.headers.get("x-forwarded-for") ?? "anonymous";
+    const { success } = await baseRateLimit.limit(ip);
+
+    if (!success) {
+      return NextResponse.json({ error: "Too many requests" }, { status: 429 });
+    }
+
+    // Check transcription configuration
+    const transcriptionCheck = isTranscriptionConfigured();
+    if (!transcriptionCheck.configured) {
+      console.error(
+        "Missing environment variables:",
+        JSON.stringify(transcriptionCheck.missingVars)
+      );
+
+      return NextResponse.json(
+        {
+          error: "Transcription not configured",
+          message: `Auto-captions require environment variables: ${transcriptionCheck.missingVars.join(", ")}. Check README for setup instructions.`,
+        },
+        { status: 503 }
+      );
+    }
+
+    // Parse and validate request body
+    const rawBody = await request.json().catch(() => null);
+    if (!rawBody) {
+      return NextResponse.json(
+        { error: "Invalid JSON in request body" },
+        { status: 400 }
+      );
+    }
+
+    const validationResult = uploadRequestSchema.safeParse(rawBody);
+    if (!validationResult.success) {
+      return NextResponse.json(
+        {
+          error: "Invalid request parameters",
+          details: validationResult.error.flatten().fieldErrors,
+        },
+        { status: 400 }
+      );
+    }
+
+    const { fileExtension } = validationResult.data;
+
+    // Initialize R2 client
+    const client = new AwsClient({
+      accessKeyId: env.R2_ACCESS_KEY_ID,
+      secretAccessKey: env.R2_SECRET_ACCESS_KEY,
+    });
+
+    // Generate unique filename with timestamp
+    const timestamp = Date.now();
+    const fileName = `audio/${timestamp}-${nanoid()}.${fileExtension}`;
+
+    // Create presigned URL
+    const url = new URL(
+      `https://${env.R2_BUCKET_NAME}.${env.CLOUDFLARE_ACCOUNT_ID}.r2.cloudflarestorage.com/${fileName}`
+    );
+
+    url.searchParams.set("X-Amz-Expires", "3600"); // 1 hour expiry
+
+    const signed = await client.sign(new Request(url, { method: "PUT" }), {
+      aws: { signQuery: true },
+    });
+
+    if (!signed.url) {
+      throw new Error("Failed to generate presigned URL");
+    }
+
+    // Prepare and validate response
+    const responseData = {
+      uploadUrl: signed.url,
+      fileName,
+    };
+
+    const responseValidation = apiResponseSchema.safeParse(responseData);
+    if (!responseValidation.success) {
+      console.error(
+        "Invalid API response structure:",
+        responseValidation.error
+      );
+      return NextResponse.json(
+        { error: "Internal response formatting error" },
+        { status: 500 }
+      );
+    }
+
+    return NextResponse.json(responseValidation.data);
+  } catch (error) {
+    console.error("Error generating upload URL:", error);
+    return NextResponse.json(
+      {
+        error: "Failed to generate upload URL",
+        message:
+          error instanceof Error
+            ? error.message
+            : "An unexpected error occurred",
+      },
+      { status: 500 }
+    );
+  }
+}

apps/web/src/app/api/transcribe/route.ts

@@ -0,0 +1,189 @@
+import { NextRequest, NextResponse } from "next/server";
+import { z } from "zod";
+import { env } from "@/env";
+import { baseRateLimit } from "@/lib/rate-limit";
+import { isTranscriptionConfigured } from "@/lib/transcription-utils";
+
+const transcribeRequestSchema = z.object({
+  filename: z.string().min(1, "Filename is required"),
+  language: z.string().optional().default("auto"),
+  decryptionKey: z.string().min(1, "Decryption key is required").optional(),
+  iv: z.string().min(1, "IV is required").optional(),
+});
+
+const modalResponseSchema = z.object({
+  text: z.string(),
+  segments: z.array(
+    z.object({
+      id: z.number(),
+      seek: z.number(),
+      start: z.number(),
+      end: z.number(),
+      text: z.string(),
+      tokens: z.array(z.number()),
+      temperature: z.number(),
+      avg_logprob: z.number(),
+      compression_ratio: z.number(),
+      no_speech_prob: z.number(),
+    })
+  ),
+  language: z.string(),
+});
+
+const apiResponseSchema = z.object({
+  text: z.string(),
+  segments: z.array(
+    z.object({
+      id: z.number(),
+      seek: z.number(),
+      start: z.number(),
+      end: z.number(),
+      text: z.string(),
+      tokens: z.array(z.number()),
+      temperature: z.number(),
+      avg_logprob: z.number(),
+      compression_ratio: z.number(),
+      no_speech_prob: z.number(),
+    })
+  ),
+  language: z.string(),
+});
+
+export async function POST(request: NextRequest) {
+  try {
+    // Rate limiting
+    const ip = request.headers.get("x-forwarded-for") ?? "anonymous";
+    const { success } = await baseRateLimit.limit(ip);
+    const origin = request.headers.get("origin");
+
+    if (!success) {
+      return NextResponse.json({ error: "Too many requests" }, { status: 429 });
+    }
+
+    // Check transcription configuration
+    const transcriptionCheck = isTranscriptionConfigured();
+    if (!transcriptionCheck.configured) {
+      console.error(
+        "Missing environment variables:",
+        JSON.stringify(transcriptionCheck.missingVars)
+      );
+
+      return NextResponse.json(
+        {
+          error: "Transcription not configured",
+          message: `Auto-captions require environment variables: ${transcriptionCheck.missingVars.join(", ")}. Check README for setup instructions.`,
+        },
+        { status: 503 }
+      );
+    }
+
+    // Parse and validate request body
+    const rawBody = await request.json().catch(() => null);
+    if (!rawBody) {
+      return NextResponse.json(
+        { error: "Invalid JSON in request body" },
+        { status: 400 }
+      );
+    }
+
+    const validationResult = transcribeRequestSchema.safeParse(rawBody);
+    if (!validationResult.success) {
+      return NextResponse.json(
+        {
+          error: "Invalid request parameters",
+          details: validationResult.error.flatten().fieldErrors,
+        },
+        { status: 400 }
+      );
+    }
+
+    const { filename, language, decryptionKey, iv } = validationResult.data;
+
+    // Prepare request body for Modal
+    const modalRequestBody: any = {
+      filename,
+      language,
+    };
+
+    // Add encryption parameters if provided (zero-knowledge)
+    if (decryptionKey && iv) {
+      modalRequestBody.decryptionKey = decryptionKey;
+      modalRequestBody.iv = iv;
+    }
+
+    // Call Modal transcription service
+    const response = await fetch(env.MODAL_TRANSCRIPTION_URL, {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify(modalRequestBody),
+    });
+
+    if (!response.ok) {
+      const errorText = await response.text();
+      console.error("Modal API error:", response.status, errorText);
+
+      let errorMessage = "Transcription service unavailable";
+      try {
+        const errorData = JSON.parse(errorText);
+        errorMessage = errorData.error || errorMessage;
+      } catch {
+        // Use default message if parsing fails
+      }
+
+      return NextResponse.json(
+        {
+          error: errorMessage,
+          message: "Failed to process transcription request",
+        },
+        { status: response.status >= 500 ? 502 : response.status }
+      );
+    }
+
+    const rawResult = await response.json();
+    console.log("Raw Modal response:", JSON.stringify(rawResult, null, 2));
+
+    // Validate Modal response
+    const modalValidation = modalResponseSchema.safeParse(rawResult);
+    if (!modalValidation.success) {
+      console.error("Invalid Modal API response:", modalValidation.error);
+      return NextResponse.json(
+        { error: "Invalid response from transcription service" },
+        { status: 502 }
+      );
+    }
+
+    const result = modalValidation.data;
+
+    // Prepare and validate API response
+    const responseData = {
+      text: result.text,
+      segments: result.segments,
+      language: result.language,
+    };
+
+    const responseValidation = apiResponseSchema.safeParse(responseData);
+    if (!responseValidation.success) {
+      console.error(
+        "Invalid API response structure:",
+        responseValidation.error
+      );
+      return NextResponse.json(
+        { error: "Internal response formatting error" },
+        { status: 500 }
+      );
+    }
+
+    return NextResponse.json(responseValidation.data);
+  } catch (error) {
+    console.error("Transcription API error:", error);
+    return NextResponse.json(
+      {
+        error: "Internal server error",
+        message: "An unexpected error occurred during transcription",
+      },
+      { status: 500 }
+    );
+  }
+}

apps/web/src/components/editor-header.tsx

@@ -180,7 +180,7 @@ function ExportButton() {
       className="flex items-center gap-1.5 bg-[#38BDF8] text-white rounded-md px-[0.1rem] py-[0.1rem] cursor-pointer hover:brightness-95 transition-all duration-200"
       onClick={handleExport}
     >
-      <div className="flex items-center gap-1.5 bg-linear-270 from-[#2567EC] to-[#37B6F7] rounded-[0.8rem] px-4 py-1 relative shadow-[0_1px_3px_0px_rgba(0,0,0,0.45)]">
+            <div className="flex items-center gap-1.5 bg-linear-270 from-[#2567EC] to-[#37B6F7] rounded-[0.8rem] px-4 py-1 relative shadow-[0_1px_3px_0px_rgba(0,0,0,0.45)]">
         <TransitionUpIcon className="z-50" />
         <span className="text-[0.875rem] z-50">Export</span>
         <div className="absolute w-full h-full left-0 top-0 bg-linear-to-t from-white/0 to-white/50 z-10 rounded-[0.8rem] flex items-center justify-center">

apps/web/src/components/editor/media-panel/views/base-view.tsx

@@ -11,12 +11,19 @@ interface BaseViewProps {
     content: React.ReactNode;
   }[];
   className?: string;
+  ref?: React.RefObject<HTMLDivElement>;
 }
 
-function ViewContent({ children }: { children: React.ReactNode }) {
+function ViewContent({
+  children,
+  className,
+}: {
+  children: React.ReactNode;
+  className?: string;
+}) {
   return (
     <ScrollArea className="flex-1">
-      <div className="p-5">{children}</div>
+      <div className={`p-5 h-full ${className}`}>{children}</div>
     </ScrollArea>
   );
 }
@@ -26,11 +33,12 @@ export function BaseView({
   defaultTab,
   tabs,
   className = "",
+  ref,
 }: BaseViewProps) {
   return (
-    <div className={`h-full flex flex-col ${className}`}>
+    <div className={`h-full flex flex-col ${className}`} ref={ref}>
       {!tabs || tabs.length === 0 ? (
-        <ViewContent>{children}</ViewContent>
+        <ViewContent className={className}>{children}</ViewContent>
       ) : (
         <Tabs defaultValue={defaultTab} className="flex flex-col h-full">
           <div className="px-3 pt-4 pb-0">

apps/web/src/components/editor/media-panel/views/captions.tsx

@@ -1,9 +1,313 @@
+import { Button } from "@/components/ui/button";
+import { PropertyGroup } from "../../properties-panel/property-item";
 import { BaseView } from "./base-view";
+import { Language, LanguageSelect } from "@/components/language-select";
+import { useState, useRef, useEffect } from "react";
+import { extractTimelineAudio } from "@/lib/ffmpeg-utils";
+import { encryptWithRandomKey, arrayBufferToBase64 } from "@/lib/zk-encryption";
+import { useTimelineStore } from "@/stores/timeline-store";
+import { Loader2, Shield, Trash2, Upload } from "lucide-react";
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
+import { TextElement } from "@/types/timeline";
+
+export const languages: Language[] = [
+  { code: "US", name: "English" },
+  { code: "ES", name: "Spanish" },
+  { code: "IT", name: "Italian" },
+  { code: "FR", name: "French" },
+  { code: "DE", name: "German" },
+  { code: "PT", name: "Portuguese" },
+  { code: "RU", name: "Russian" },
+  { code: "JP", name: "Japanese" },
+  { code: "CN", name: "Chinese" },
+];
+
+const PRIVACY_DIALOG_KEY = "opencut-transcription-privacy-accepted";
 
 export function Captions() {
+  const [selectedCountry, setSelectedCountry] = useState("auto");
+  const [isProcessing, setIsProcessing] = useState(false);
+  const [processingStep, setProcessingStep] = useState<string>("");
+  const [error, setError] = useState<string | null>(null);
+  const [showPrivacyDialog, setShowPrivacyDialog] = useState(false);
+  const [hasAcceptedPrivacy, setHasAcceptedPrivacy] = useState(false);
+  const containerRef = useRef<HTMLDivElement>(null);
+  const { insertTrackAt, addElementToTrack } = useTimelineStore();
+
+  // Check if user has already accepted privacy on mount
+  useEffect(() => {
+    const hasAccepted = localStorage.getItem(PRIVACY_DIALOG_KEY) === "true";
+    setHasAcceptedPrivacy(hasAccepted);
+  }, []);
+
+  const handleGenerateTranscript = async () => {
+    try {
+      setIsProcessing(true);
+      setError(null);
+      setProcessingStep("Extracting audio...");
+
+      const audioBlob = await extractTimelineAudio();
+
+      setProcessingStep("Encrypting audio...");
+
+      // Encrypt the audio with a random key (zero-knowledge)
+      const audioBuffer = await audioBlob.arrayBuffer();
+      const encryptionResult = await encryptWithRandomKey(audioBuffer);
+
+      // Convert encrypted data to blob for upload
+      const encryptedBlob = new Blob([encryptionResult.encryptedData]);
+
+      setProcessingStep("Uploading...");
+      const uploadResponse = await fetch("/api/get-upload-url", {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ fileExtension: "wav" }),
+      });
+
+      if (!uploadResponse.ok) {
+        const error = await uploadResponse.json();
+        throw new Error(error.message || "Failed to get upload URL");
+      }
+
+      const { uploadUrl, fileName } = await uploadResponse.json();
+
+      // Upload to R2
+      await fetch(uploadUrl, {
+        method: "PUT",
+        body: encryptedBlob,
+      });
+
+      setProcessingStep("Transcribing...");
+
+      // Call Modal transcription API with encryption parameters
+      const transcriptionResponse = await fetch("/api/transcribe", {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({
+          filename: fileName,
+          language:
+            selectedCountry === "auto" ? "auto" : selectedCountry.toLowerCase(),
+          // Send the raw encryption key and IV (zero-knowledge)
+          decryptionKey: arrayBufferToBase64(encryptionResult.key),
+          iv: arrayBufferToBase64(encryptionResult.iv),
+        }),
+      });
+
+      if (!transcriptionResponse.ok) {
+        const error = await transcriptionResponse.json();
+        throw new Error(error.message || "Transcription failed");
+      }
+
+      const { text, segments } = await transcriptionResponse.json();
+
+      console.log("Transcription completed:", { text, segments });
+
+      const shortCaptions: Array<{
+        text: string;
+        startTime: number;
+        duration: number;
+      }> = [];
+
+      let globalEndTime = 0; // Track the end time of the last caption globally
+
+      segments.forEach((segment: any) => {
+        const words = segment.text.trim().split(/\s+/);
+        const segmentDuration = segment.end - segment.start;
+        const wordsPerSecond = words.length / segmentDuration;
+
+        // Split into chunks of 2-4 words
+        const chunks: string[] = [];
+        for (let i = 0; i < words.length; i += 3) {
+          chunks.push(words.slice(i, i + 3).join(" "));
+        }
+
+        // Calculate timing for each chunk to place them sequentially
+        let chunkStartTime = segment.start;
+        chunks.forEach((chunk) => {
+          const chunkWords = chunk.split(/\s+/).length;
+          const chunkDuration = Math.max(0.8, chunkWords / wordsPerSecond); // Minimum 0.8s per chunk
+
+          let adjustedStartTime = chunkStartTime;
+
+          // Prevent overlapping: if this caption would start before the last one ends,
+          // start it right after the last one ends
+          if (adjustedStartTime < globalEndTime) {
+            adjustedStartTime = globalEndTime;
+          }
+
+          shortCaptions.push({
+            text: chunk,
+            startTime: adjustedStartTime,
+            duration: chunkDuration,
+          });
+
+          // Update global end time
+          globalEndTime = adjustedStartTime + chunkDuration;
+
+          // Next chunk starts when this one ends (for within-segment timing)
+          chunkStartTime += chunkDuration;
+        });
+      });
+
+      // Create a single track for all captions
+      const captionTrackId = insertTrackAt("text", 0);
+
+      // Add all caption elements to the same track
+      shortCaptions.forEach((caption, index) => {
+        addElementToTrack(captionTrackId, {
+          type: "text",
+          name: `Caption ${index + 1}`,
+          content: caption.text,
+          duration: caption.duration,
+          startTime: caption.startTime,
+          trimStart: 0,
+          trimEnd: 0,
+          fontSize: 65,
+          fontFamily: "Arial",
+          color: "#ffffff",
+          textAlign: "center",
+          fontWeight: "bold",
+          fontStyle: "normal",
+          textDecoration: "none",
+          x: 0,
+          y: 0,
+          rotation: 0,
+          opacity: 1,
+        } as TextElement);
+      });
+
+      console.log(
+        `✅ ${shortCaptions.length} short-form caption chunks added to timeline!`
+      );
+    } catch (error) {
+      console.error("Transcription failed:", error);
+      setError(
+        error instanceof Error ? error.message : "An unexpected error occurred"
+      );
+    } finally {
+      setIsProcessing(false);
+      setProcessingStep("");
+    }
+  };
+
   return (
-    <BaseView>
+    <BaseView ref={containerRef} className="flex flex-col justify-between">
-      <div>Captions</div>
+      <PropertyGroup title="Language">
+        <LanguageSelect
+          selectedCountry={selectedCountry}
+          onSelect={setSelectedCountry}
+          containerRef={containerRef}
+          languages={languages}
+        />
+      </PropertyGroup>
+
+      <div className="flex flex-col gap-4">
+        {error && (
+          <div className="p-3 bg-destructive/10 border border-destructive/20 rounded-md">
+            <p className="text-sm text-destructive">{error}</p>
+          </div>
+        )}
+
+        <Button
+          className="w-full"
+          onClick={() => {
+            if (hasAcceptedPrivacy) {
+              handleGenerateTranscript();
+            } else {
+              setShowPrivacyDialog(true);
+            }
+          }}
+          disabled={isProcessing}
+        >
+          {isProcessing && <Loader2 className="mr-1 h-4 w-4 animate-spin" />}
+          {isProcessing ? processingStep : "Generate transcript"}
+        </Button>
+
+        <Dialog open={showPrivacyDialog} onOpenChange={setShowPrivacyDialog}>
+          <DialogContent className="sm:max-w-md">
+            <DialogHeader>
+              <DialogTitle className="flex items-center gap-2">
+                <Shield className="h-5 w-5" />
+                Audio Processing Notice
+              </DialogTitle>
+              <DialogDescription className="space-y-3">
+                <p>
+                  To generate captions, we need to process your timeline audio
+                  using speech-to-text technology.
+                </p>
+
+                <div className="space-y-2 pt-2">
+                  <div className="flex items-start gap-2">
+                    <Shield className="h-4 w-4 flex-shrink-0" />
+                    <span className="text-sm">
+                      Zero-knowledge encryption - we cannot decrypt your files
+                      even if we wanted to
+                    </span>
+                  </div>
+
+                  <div className="flex items-start gap-2">
+                    <Shield className="h-4 w-4 flex-shrink-0" />
+                    <span className="text-sm">
+                      Encryption keys generated randomly in your browser, never
+                      stored anywhere
+                    </span>
+                  </div>
+
+                  <div className="flex items-start gap-2">
+                    <Upload className="h-4 w-4 flex-shrink-0" />
+                    <span className="text-sm">
+                      Audio encrypted before upload - raw audio never leaves
+                      your device
+                    </span>
+                  </div>
+
+                  <div className="flex items-start gap-2">
+                    <Trash2 className="h-4 w-4 flex-shrink-0" />
+                    <span className="text-sm">
+                      Everything permanently deleted within seconds after
+                      transcription
+                    </span>
+                  </div>
+                </div>
+
+                <p className="text-xs text-muted-foreground">
+                  <strong>True zero-knowledge privacy:</strong> Encryption keys
+                  are generated randomly in your browser and never stored
+                  anywhere. It's cryptographically impossible for us, our cloud
+                  providers, or anyone else to decrypt your audio files.
+                </p>
+              </DialogDescription>
+            </DialogHeader>
+            <DialogFooter className="gap-2">
+              <Button
+                variant="outline"
+                onClick={() => setShowPrivacyDialog(false)}
+                disabled={isProcessing}
+              >
+                Cancel
+              </Button>
+              <Button
+                onClick={() => {
+                  localStorage.setItem(PRIVACY_DIALOG_KEY, "true");
+                  setHasAcceptedPrivacy(true);
+                  setShowPrivacyDialog(false);
+                  handleGenerateTranscript();
+                }}
+                disabled={isProcessing}
+              >
+                Continue & Generate Captions
+              </Button>
+            </DialogFooter>
+          </DialogContent>
+        </Dialog>
+      </div>
     </BaseView>
   );
 }

apps/web/src/components/editor/preview-panel.tsx

@@ -356,7 +356,7 @@ export function PreviewPanel() {
       return (
         <div
           key={element.id}
-          className="absolute flex items-center justify-center cursor-grab"
+          className="absolute cursor-grab"
           onMouseDown={(e) =>
             handleTextMouseDown(e, element, elementData.track.id)
           }
@@ -377,7 +377,7 @@ export function PreviewPanel() {
                 canvasSize.height) *
                 100
             }%`,
-            transform: `translate(-50%, -50%) rotate(${element.rotation}deg) scale(${scaleRatio})`,
+            transform: `translate(-50%, -50%) rotate(${element.rotation}deg)`,
             opacity: element.opacity,
             zIndex: 100 + index, // Text elements on top
           }}
@@ -385,16 +385,16 @@ export function PreviewPanel() {
           <div
             className={fontClassName}
             style={{
-              fontSize: `${element.fontSize}px`,
+              fontSize: `${element.fontSize * scaleRatio}px`,
               color: element.color,
               backgroundColor: element.backgroundColor,
               textAlign: element.textAlign,
               fontWeight: element.fontWeight,
               fontStyle: element.fontStyle,
               textDecoration: element.textDecoration,
-              padding: "4px 8px",
+              padding: `${4 * scaleRatio}px ${8 * scaleRatio}px`,
-              borderRadius: "2px",
+              borderRadius: `${2 * scaleRatio}px`,
-              whiteSpace: "pre-wrap",
+              whiteSpace: "nowrap",
               // Fallback for system fonts that don't have classes
               ...(fontClassName === "" && { fontFamily: element.fontFamily }),
             }}

apps/web/src/components/language-select.tsx

@@ -0,0 +1,204 @@
+import { useState, useRef, useEffect } from "react";
+import { ChevronDown, Globe } from "lucide-react";
+import { cn } from "@/lib/utils";
+import { motion } from "framer-motion";
+import ReactCountryFlag from "react-country-flag";
+
+export interface Language {
+  code: string;
+  name: string;
+  flag?: string;
+}
+
+interface LanguageSelectProps {
+  selectedCountry: string;
+  onSelect: (country: string) => void;
+  containerRef: React.RefObject<HTMLDivElement>;
+  languages: Language[];
+}
+
+function FlagPreloader({ languages }: { languages: Language[] }) {
+  return (
+    <div className="absolute -top-[9999px] left-0 pointer-events-none">
+      {languages.map((language) => (
+        <ReactCountryFlag
+          key={language.code}
+          countryCode={language.code}
+          svg
+          style={{ width: "1.05rem", height: "1.05rem" }}
+        />
+      ))}
+    </div>
+  );
+}
+
+export function LanguageSelect({
+  selectedCountry,
+  onSelect,
+  containerRef,
+  languages,
+}: LanguageSelectProps) {
+  const [expanded, setExpanded] = useState(false);
+  const [isTapping, setIsTapping] = useState(false);
+  const [isClosing, setIsClosing] = useState(false);
+  const collapsedHeight = "2.5rem";
+  const expandHeight = "12rem";
+  const buttonRef = useRef<HTMLButtonElement>(null);
+
+  const expand = () => {
+    setIsTapping(true);
+    setTimeout(() => setIsTapping(false), 600);
+    setExpanded(true);
+    buttonRef.current?.focus();
+  };
+
+  useEffect(() => {
+    if (!expanded) return;
+
+    const handleClickOutside = (event: MouseEvent) => {
+      if (
+        buttonRef.current &&
+        !buttonRef.current.contains(event.target as Node)
+      ) {
+        setIsClosing(true);
+        setTimeout(() => setIsClosing(false), 600);
+        setExpanded(false);
+        buttonRef.current?.blur();
+      }
+    };
+
+    document.addEventListener("mousedown", handleClickOutside);
+    return () => {
+      document.removeEventListener("mousedown", handleClickOutside);
+    };
+  }, [expanded]);
+
+  const selectedLanguage = languages.find(
+    (lang) => lang.code === selectedCountry
+  );
+
+  const handleSelect = ({
+    code,
+    e,
+  }: {
+    code: string;
+    e: React.MouseEvent<HTMLButtonElement>;
+  }) => {
+    e.stopPropagation();
+    e.preventDefault();
+    onSelect(code);
+    setExpanded(false);
+  };
+
+  return (
+    <div className="relative w-full h-9">
+      <FlagPreloader languages={languages} />
+      <motion.button
+        type="button"
+        className={cn(
+          "absolute w-full h-full flex flex-col overflow-hidden items-start justify-between z-10 rounded-lg px-3 cursor-pointer",
+          "!bg-foreground/10 backdrop-blur-md text-foreground py-0",
+          "transition-[color,box-shadow] focus:border-ring focus:ring-ring/50 focus:ring-[1px]"
+        )}
+        initial={{
+          height: collapsedHeight,
+          scale: 1,
+        }}
+        animate={{
+          height: expanded ? expandHeight : collapsedHeight,
+          scale: isTapping ? [1, 0.985, 1] : 1,
+        }}
+        transition={{
+          height: { duration: 0.25, ease: [0.4, 0, 0.2, 1] },
+          scale: { duration: 0.6, ease: "easeOut" },
+        }}
+        onClick={expand}
+        ref={buttonRef}
+      >
+        {!expanded ? (
+          <div
+            className="flex items-center justify-between w-full"
+            style={{
+              height: collapsedHeight,
+            }}
+          >
+            <div className="flex items-center gap-2">
+              {selectedCountry === "auto" ? (
+                <Globe className="!size-[1.05rem]" />
+              ) : (
+                <ReactCountryFlag
+                  countryCode={selectedCountry}
+                  svg
+                  style={{ width: "1.05rem", height: "1.05rem" }}
+                />
+              )}
+              <span className="pt-[0.05rem]">
+                {selectedCountry === "auto" ? "Auto" : selectedLanguage?.name}
+              </span>
+            </div>
+          </div>
+        ) : (
+          <div className="flex flex-col gap-2 my-2.5 w-full overflow-y-auto scrollbar-hidden">
+            <LanguageButton
+              language={{ code: "auto", name: "Auto" }}
+              onSelect={handleSelect}
+              selectedCountry={selectedCountry}
+            />
+            {languages.map((language) => (
+              <LanguageButton
+                key={language.code}
+                language={language}
+                onSelect={handleSelect}
+                selectedCountry={selectedCountry}
+              />
+            ))}
+          </div>
+        )}
+      </motion.button>
+
+      <motion.div
+        className="absolute top-1/2 right-3 -translate-y-1/2 pointer-events-none z-20 mt-0.5"
+        initial={{ opacity: 1 }}
+        animate={{ opacity: expanded ? 0 : 1 }}
+        transition={{ duration: 0.2, ease: "easeInOut" }}
+      >
+        <ChevronDown className="text-muted-foreground size-4" />
+      </motion.div>
+    </div>
+  );
+}
+
+function LanguageButton({
+  language,
+  onSelect,
+  selectedCountry,
+}: {
+  language: Language;
+  onSelect: ({
+    code,
+    e,
+  }: {
+    code: string;
+    e: React.MouseEvent<HTMLButtonElement>;
+  }) => void;
+  selectedCountry: string;
+}) {
+  return (
+    <button
+      type="button"
+      className="flex items-center gap-2 cursor-pointer text-foreground hover:text-foreground/75"
+      onClick={(e) => onSelect({ code: language.code, e })}
+    >
+      {language.code === "auto" ? (
+        <Globe className="!size-[1.0rem]" />
+      ) : (
+        <ReactCountryFlag
+          countryCode={language.code}
+          svg
+          style={{ width: "1.05rem", height: "1.05rem" }}
+        />
+      )}
+      <span className="pt-[0.05rem]">{language.name}</span>
+    </button>
+  );
+}

apps/web/src/components/onboarding.tsx

@@ -79,7 +79,7 @@ export function Onboarding() {
 
   return (
     <Dialog open={isOpen} onOpenChange={handleClose}>
-      <DialogContent className="sm:max-w-[425px] outline-hidden!">
+      <DialogContent className="sm:max-w-[425px] !outline-none">
         <DialogTitle>
           <span className="sr-only">{getStepTitle()}</span>
         </DialogTitle>

apps/web/src/components/ui/button.tsx

@@ -13,6 +13,8 @@ const buttonVariants = cva(
           "bg-foreground text-background shadow-sm hover:bg-foreground/90",
         primary:
           "bg-primary text-primary-foreground shadow-sm hover:bg-primary/90",
+        "primary-gradient":
+          "bg-gradient-to-r from-cyan-400 to-blue-500 text-white hover:opacity-85 transition-opacity",
         destructive:
           "bg-destructive text-destructive-foreground shadow-xs hover:bg-destructive/90",
         outline:

apps/web/src/env.ts

@@ -17,6 +17,13 @@ export const env = createEnv({
     UPSTASH_REDIS_REST_TOKEN: z.string(),
     FREESOUND_CLIENT_ID: z.string(),
     FREESOUND_API_KEY: z.string(),
+    // R2 / Cloudflare
+    CLOUDFLARE_ACCOUNT_ID: z.string(),
+    R2_ACCESS_KEY_ID: z.string(),
+    R2_SECRET_ACCESS_KEY: z.string(),
+    R2_BUCKET_NAME: z.string(),
+    // Modal transcription
+    MODAL_TRANSCRIPTION_URL: z.string(),
   },
   client: {},
   runtimeEnv: {
@@ -27,5 +34,12 @@ export const env = createEnv({
     UPSTASH_REDIS_REST_TOKEN: process.env.UPSTASH_REDIS_REST_TOKEN,
     FREESOUND_CLIENT_ID: process.env.FREESOUND_CLIENT_ID,
     FREESOUND_API_KEY: process.env.FREESOUND_API_KEY,
+    // R2 / Cloudflare
+    CLOUDFLARE_ACCOUNT_ID: process.env.CLOUDFLARE_ACCOUNT_ID,
+    R2_ACCESS_KEY_ID: process.env.R2_ACCESS_KEY_ID,
+    R2_SECRET_ACCESS_KEY: process.env.R2_SECRET_ACCESS_KEY,
+    R2_BUCKET_NAME: process.env.R2_BUCKET_NAME,
+    // Modal transcription
+    MODAL_TRANSCRIPTION_URL: process.env.MODAL_TRANSCRIPTION_URL,
   },
 });

apps/web/src/lib/ffmpeg-utils.ts

@@ -1,5 +1,7 @@
 import { FFmpeg } from "@ffmpeg/ffmpeg";
 import { toBlobURL } from "@ffmpeg/util";
+import { useTimelineStore } from "@/stores/timeline-store";
+import { useMediaStore } from "@/stores/media-store";
 
 let ffmpeg: FFmpeg | null = null;
 
@@ -7,14 +9,7 @@ export const initFFmpeg = async (): Promise<FFmpeg> => {
   if (ffmpeg) return ffmpeg;
 
   ffmpeg = new FFmpeg();
-
+  await ffmpeg.load(); // Use default config
-  // Use locally hosted files instead of CDN
-  const baseURL = "/ffmpeg";
-
-  await ffmpeg.load({
-    coreURL: await toBlobURL(`${baseURL}/ffmpeg-core.js`, "text/javascript"),
-    wasmURL: await toBlobURL(`${baseURL}/ffmpeg-core.wasm`, "application/wasm"),
-  });
 
   return ffmpeg;
 };
@@ -268,3 +263,206 @@ export const extractAudio = async (
 
   return blob;
 };
+
+export const extractTimelineAudio = async (
+  onProgress?: (progress: number) => void
+): Promise<Blob> => {
+  // Create fresh FFmpeg instance for this operation
+  const ffmpeg = new FFmpeg();
+
+  try {
+    await ffmpeg.load();
+  } catch (error) {
+    console.error("Failed to load fresh FFmpeg instance:", error);
+    throw new Error("Unable to initialize audio processing. Please try again.");
+  }
+
+  const timeline = useTimelineStore.getState();
+  const mediaStore = useMediaStore.getState();
+
+  const tracks = timeline.tracks;
+  const totalDuration = timeline.getTotalDuration();
+
+  if (totalDuration === 0) {
+    const emptyAudioData = new ArrayBuffer(44);
+    return new Blob([emptyAudioData], { type: "audio/wav" });
+  }
+
+  if (onProgress) {
+    ffmpeg.on("progress", ({ progress }) => {
+      onProgress(progress * 100);
+    });
+  }
+
+  const audioElements: Array<{
+    file: File;
+    startTime: number;
+    duration: number;
+    trimStart: number;
+    trimEnd: number;
+    trackMuted: boolean;
+  }> = [];
+
+  for (const track of tracks) {
+    if (track.muted) continue;
+
+    for (const element of track.elements) {
+      if (element.type === "media") {
+        const mediaItem = mediaStore.mediaItems.find(
+          (m) => m.id === element.mediaId
+        );
+        if (!mediaItem) continue;
+
+        if (mediaItem.type === "video" || mediaItem.type === "audio") {
+          audioElements.push({
+            file: mediaItem.file,
+            startTime: element.startTime,
+            duration: element.duration,
+            trimStart: element.trimStart,
+            trimEnd: element.trimEnd,
+            trackMuted: track.muted || false,
+          });
+        }
+      }
+    }
+  }
+
+  if (audioElements.length === 0) {
+    // Return silent audio if no audio elements
+    const silentDuration = Math.max(1, totalDuration); // At least 1 second
+    try {
+      const silentAudio = await generateSilentAudio(silentDuration);
+      return silentAudio;
+    } catch (error) {
+      console.error("Failed to generate silent audio:", error);
+      throw new Error("Unable to generate audio for empty timeline.");
+    }
+  }
+
+  // Create a complex filter to mix all audio sources
+  const inputFiles: string[] = [];
+  const filterInputs: string[] = [];
+
+  try {
+    for (let i = 0; i < audioElements.length; i++) {
+      const element = audioElements[i];
+      const inputName = `input_${i}.${element.file.name.split(".").pop()}`;
+      inputFiles.push(inputName);
+
+      try {
+        await ffmpeg.writeFile(
+          inputName,
+          new Uint8Array(await element.file.arrayBuffer())
+        );
+      } catch (error) {
+        console.error(`Failed to write file ${element.file.name}:`, error);
+        throw new Error(
+          `Unable to process file: ${element.file.name}. The file may be corrupted or in an unsupported format.`
+        );
+      }
+
+      const actualStart = element.trimStart;
+      const actualDuration =
+        element.duration - element.trimStart - element.trimEnd;
+
+      const filterName = `audio_${i}`;
+      filterInputs.push(
+        `[${i}:a]atrim=start=${actualStart}:duration=${actualDuration},asetpts=PTS-STARTPTS,adelay=${element.startTime * 1000}|${element.startTime * 1000}[${filterName}]`
+      );
+    }
+
+    const mixFilter =
+      audioElements.length === 1
+        ? `[audio_0]aresample=44100,aformat=sample_fmts=s16:channel_layouts=stereo[out]`
+        : `${filterInputs.map((_, i) => `[audio_${i}]`).join("")}amix=inputs=${audioElements.length}:duration=longest:dropout_transition=2,aresample=44100,aformat=sample_fmts=s16:channel_layouts=stereo[out]`;
+
+    const complexFilter = [...filterInputs, mixFilter].join(";");
+    const outputName = "timeline_audio.wav";
+
+    const ffmpegArgs = [
+      ...inputFiles.flatMap((name) => ["-i", name]),
+      "-filter_complex",
+      complexFilter,
+      "-map",
+      "[out]",
+      "-t",
+      totalDuration.toString(),
+      "-c:a",
+      "pcm_s16le",
+      "-ar",
+      "44100",
+      outputName,
+    ];
+
+    try {
+      await ffmpeg.exec(ffmpegArgs);
+    } catch (error) {
+      console.error("FFmpeg execution failed:", error);
+      throw new Error(
+        "Audio processing failed. Some audio files may be corrupted or incompatible."
+      );
+    }
+
+    const data = await ffmpeg.readFile(outputName);
+    const blob = new Blob([data], { type: "audio/wav" });
+
+    return blob;
+  } catch (error) {
+    for (const inputFile of inputFiles) {
+      try {
+        await ffmpeg.deleteFile(inputFile);
+      } catch (cleanupError) {
+        console.warn(`Failed to cleanup file ${inputFile}:`, cleanupError);
+      }
+    }
+    try {
+      await ffmpeg.deleteFile("timeline_audio.wav");
+    } catch (cleanupError) {
+      console.warn("Failed to cleanup output file:", cleanupError);
+    }
+
+    throw error;
+  } finally {
+    for (const inputFile of inputFiles) {
+      try {
+        await ffmpeg.deleteFile(inputFile);
+      } catch (cleanupError) {}
+    }
+    try {
+      await ffmpeg.deleteFile("timeline_audio.wav");
+    } catch (cleanupError) {}
+  }
+};
+
+const generateSilentAudio = async (durationSeconds: number): Promise<Blob> => {
+  const ffmpeg = await initFFmpeg();
+  const outputName = "silent.wav";
+
+  try {
+    await ffmpeg.exec([
+      "-f",
+      "lavfi",
+      "-i",
+      `anullsrc=channel_layout=stereo:sample_rate=44100`,
+      "-t",
+      durationSeconds.toString(),
+      "-c:a",
+      "pcm_s16le",
+      outputName,
+    ]);
+
+    const data = await ffmpeg.readFile(outputName);
+    const blob = new Blob([data], { type: "audio/wav" });
+
+    return blob;
+  } catch (error) {
+    console.error("Failed to generate silent audio:", error);
+    throw error;
+  } finally {
+    try {
+      await ffmpeg.deleteFile(outputName);
+    } catch (cleanupError) {
+      // Silent cleanup
+    }
+  }
+};

apps/web/src/lib/transcription-utils.ts

@@ -0,0 +1,13 @@
+import { env } from "@/env";
+
+export function isTranscriptionConfigured() {
+  const missingVars = [];
+
+  if (!env.CLOUDFLARE_ACCOUNT_ID) missingVars.push("CLOUDFLARE_ACCOUNT_ID");
+  if (!env.R2_ACCESS_KEY_ID) missingVars.push("R2_ACCESS_KEY_ID");
+  if (!env.R2_SECRET_ACCESS_KEY) missingVars.push("R2_SECRET_ACCESS_KEY");
+  if (!env.R2_BUCKET_NAME) missingVars.push("R2_BUCKET_NAME");
+  if (!env.MODAL_TRANSCRIPTION_URL) missingVars.push("MODAL_TRANSCRIPTION_URL");
+
+  return { configured: missingVars.length === 0, missingVars };
+}

apps/web/src/lib/zk-encryption.ts

@@ -0,0 +1,71 @@
+/**
+ * True zero-knowledge encryption utilities
+ * Keys are generated randomly in the browser and never derived from server secrets
+ */
+
+export interface ZeroKnowledgeEncryptionResult {
+  encryptedData: ArrayBuffer;
+  key: ArrayBuffer;
+  iv: ArrayBuffer;
+}
+
+/**
+ * Encrypt data with a randomly generated key (true zero-knowledge)
+ */
+export async function encryptWithRandomKey(
+  data: ArrayBuffer
+): Promise<ZeroKnowledgeEncryptionResult> {
+  // Generate a truly random 256-bit key
+  const key = crypto.getRandomValues(new Uint8Array(32));
+
+  // Generate random IV
+  const iv = crypto.getRandomValues(new Uint8Array(12));
+
+  // Import the key for encryption
+  const cryptoKey = await crypto.subtle.importKey(
+    "raw",
+    key,
+    { name: " " },
+    false,
+    ["encrypt"]
+  );
+
+  // Encrypt the data
+  const encryptedResult = await crypto.subtle.encrypt(
+    { name: "AES-GCM", iv },
+    cryptoKey,
+    data
+  );
+
+  // For AES-GCM, we need to append the authentication tag
+  // The encrypted result contains both ciphertext and tag
+  return {
+    encryptedData: encryptedResult,
+    key: key.buffer,
+    iv: iv.buffer,
+  };
+}
+
+/**
+ * Convert ArrayBuffer to base64 string for transmission
+ */
+export function arrayBufferToBase64(buffer: ArrayBuffer): string {
+  const bytes = new Uint8Array(buffer);
+  let binary = "";
+  for (let i = 0; i < bytes.byteLength; i++) {
+    binary += String.fromCharCode(bytes[i]);
+  }
+  return btoa(binary);
+}
+
+/**
+ * Convert base64 string back to ArrayBuffer
+ */
+export function base64ToArrayBuffer(base64: string): ArrayBuffer {
+  const binary = atob(base64);
+  const bytes = new Uint8Array(binary.length);
+  for (let i = 0; i < binary.length; i++) {
+    bytes[i] = binary.charCodeAt(i);
+  }
+  return bytes.buffer;
+}

bun.lock

@@ -5,6 +5,7 @@
       "name": "opencut",
       "dependencies": {
         "next": "^15.3.4",
+        "react-country-flag": "^3.1.0",
         "wavesurfer.js": "^7.9.8",
       },
       "devDependencies": {
@@ -32,6 +33,7 @@
         "@upstash/ratelimit": "^2.0.5",
         "@upstash/redis": "^1.35.0",
         "@vercel/analytics": "^1.4.1",
+        "aws4fetch": "^1.0.20",
         "better-auth": "^1.2.7",
         "botid": "^1.4.2",
         "class-variance-authority": "^0.7.1",
@@ -46,6 +48,7 @@
         "input-otp": "^1.4.1",
         "lucide-react": "^0.468.0",
         "motion": "^12.18.1",
+        "nanoid": "^5.1.5",
         "next": "^15.4.5",
         "next-themes": "^0.4.4",
         "pg": "^8.16.2",
@@ -608,6 +611,8 @@
 
     "assertion-error": ["assertion-error@2.0.1", "", {}, "sha512-Izi8RQcffqCeNVgFigKli1ssklIbpHnCYc6AknXGYoB6grJqyeby7jv12JUQgmTAnIDnbck1uxksT4dzN3PWBA=="],
 
+    "aws4fetch": ["aws4fetch@1.0.20", "", {}, "sha512-/djoAN709iY65ETD6LKCtyyEI04XIBP5xVvfmNxsEP0uJB5tyaGBztSryRr4HqMStr9R06PisQE7m9zDTXKu6g=="],
+
     "bail": ["bail@2.0.2", "", {}, "sha512-0xO6mYd7JB2YesxDKplafRpsiOzPt9V02ddPCLbY1xYGPOX24NTyN50qnUxgCPcSoYMhKpAuBTjQoRZCAkUDRw=="],
 
     "better-auth": ["better-auth@1.3.2", "", { "dependencies": { "@better-auth/utils": "0.2.5", "@better-fetch/fetch": "^1.1.18", "@noble/ciphers": "^0.6.0", "@noble/hashes": "^1.8.0", "@simplewebauthn/browser": "^13.0.0", "@simplewebauthn/server": "^13.0.0", "better-call": "^1.0.12", "defu": "^6.1.4", "jose": "^5.9.6", "kysely": "^0.28.1", "nanostores": "^0.11.3", "zod": "^4.0.5" }, "peerDependencies": { "react": "^18.0.0 || ^19.0.0", "react-dom": "^18.0.0 || ^19.0.0" }, "optionalPeers": ["react", "react-dom"] }, "sha512-510kOtFBTdp4z51hWtTEqk9yqSinXzyg7PkDFnXYMq1K0KvdXRY1A9t9J998i0CSf/tJA0wNoN3S8exkOgBvTw=="],
@@ -946,7 +951,7 @@
 
     "ms": ["ms@2.1.3", "", {}, "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA=="],
 
-    "nanoid": ["nanoid@3.3.11", "", { "bin": { "nanoid": "bin/nanoid.cjs" } }, "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w=="],
+    "nanoid": ["nanoid@5.1.5", "", { "bin": { "nanoid": "bin/nanoid.js" } }, "sha512-Ir/+ZpE9fDsNH0hQ3C68uyThDXzYcim2EqcZ8zn8Chtt1iylPT9xXJB0kPCnqzgcEGikO9RxSrh63MsmVCU7Fw=="],
 
     "nanostores": ["nanostores@0.11.4", "", {}, "sha512-k1oiVNN4hDK8NcNERSZLQiMfRzEGtfnvZvdBvey3SQbgn8Dcrk0h1I6vpxApjb10PFUflZrgJ2WEZyJQ+5v7YQ=="],
 
@@ -1016,6 +1021,8 @@
 
     "react": ["react@18.3.1", "", { "dependencies": { "loose-envify": "^1.1.0" } }, "sha512-wS+hAgJShR0KhEvPJArfuPVN1+Hz1t0Y6n5jLrGQbkb4urgPE/0Rve+1kMB1v/oWgHgm4WIcV+i7F2pTVj+2iQ=="],
 
+    "react-country-flag": ["react-country-flag@3.1.0", "", { "peerDependencies": { "react": ">=16" } }, "sha512-JWQFw1efdv9sTC+TGQvTKXQg1NKbDU2mBiAiRWcKM9F1sK+/zjhP2yGmm8YDddWyZdXVkR8Md47rPMJmo4YO5g=="],
+
     "react-day-picker": ["react-day-picker@8.10.1", "", { "peerDependencies": { "date-fns": "^2.28.0 || ^3.0.0", "react": "^16.8.0 || ^17.0.0 || ^18.0.0" } }, "sha512-TMx7fNbhLk15eqcMt+7Z7S2KF7mfTId/XJDjKE8f+IUcFn0l08/kI4FiYTL/0yuOLmEcbR4Fwe3GJf/NiiMnPA=="],
 
     "react-dom": ["react-dom@18.3.1", "", { "dependencies": { "loose-envify": "^1.1.0", "scheduler": "^0.23.2" }, "peerDependencies": { "react": "^18.3.1" } }, "sha512-5m4nQKp+rZRb09LNH59GM4BxTh9251/ylbKIbpe7TpGxfJ+9kv6BLkLBXIjjspbgbnIBNqlI23tRnTWT0snUIw=="],
@@ -1254,6 +1261,8 @@
 
     "parse-entities/@types/unist": ["@types/unist@2.0.11", "", {}, "sha512-CmBKiL6NNo/OqgmMn95Fk9Whlp2mtvIv+KNpQKN2F4SjvrEesubTRWGYSg+BnWZOnlCaSTU1sMpsBOzgbYhnsA=="],
 
+    "postcss/nanoid": ["nanoid@3.3.11", "", { "bin": { "nanoid": "bin/nanoid.cjs" } }, "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w=="],
+
     "prop-types/react-is": ["react-is@16.13.1", "", {}, "sha512-24e6ynE2H+OKt4kqsOvNd8kBpV65zoxbA4BVsEOB3ARVWQki/DHzaUoC5KuON/BiccDaCCTZBuOcfZs70kR8bQ=="],
 
     "strip-literal/js-tokens": ["js-tokens@9.0.1", "", {}, "sha512-mxa9E9ITFOt0ban3j6L5MpjwegGz6lBQmM1IJkWeBZGcMxto50+eWdjC/52xDbS2vy0k7vIMK0Fe2wfL9OQSpQ=="],
@@ -1308,6 +1317,8 @@
 
     "motion/framer-motion/motion-utils": ["motion-utils@12.23.6", "", {}, "sha512-eAWoPgr4eFEOFfg2WjIsMoqJTW6Z8MTUCgn/GZ3VRpClWBdnbjryiA3ZSNLyxCTmCQx4RmYX6jX1iWHbenUPNQ=="],
 
+    "next/postcss/nanoid": ["nanoid@3.3.11", "", { "bin": { "nanoid": "bin/nanoid.cjs" } }, "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w=="],
+
     "opencut/next/@next/env": ["@next/env@15.4.5", "", {}, "sha512-ruM+q2SCOVCepUiERoxOmZY9ZVoecR3gcXNwCYZRvQQWRjhOiPJGmQ2fAiLR6YKWXcSAh7G79KEFxN3rwhs4LQ=="],
 
     "opencut/next/@next/swc-darwin-arm64": ["@next/swc-darwin-arm64@15.4.5", "", { "os": "darwin", "cpu": "arm64" }, "sha512-84dAN4fkfdC7nX6udDLz9GzQlMUwEMKD7zsseXrl7FTeIItF8vpk1lhLEnsotiiDt+QFu3O1FVWnqwcRD2U3KA=="],
@@ -1327,5 +1338,7 @@
     "opencut/next/@next/swc-win32-x64-msvc": ["@next/swc-win32-x64-msvc@15.4.5", "", { "os": "win32", "cpu": "x64" }, "sha512-voWk7XtGvlsP+w8VBz7lqp8Y+dYw/MTI4KeS0gTVtfdhdJ5QwhXLmNrndFOin/MDoCvUaLWMkYKATaCoUkt2/A=="],
 
     "opencut/next/postcss": ["postcss@8.4.31", "", { "dependencies": { "nanoid": "^3.3.6", "picocolors": "^1.0.0", "source-map-js": "^1.0.2" } }, "sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ=="],
+
+    "opencut/next/postcss/nanoid": ["nanoid@3.3.11", "", { "bin": { "nanoid": "bin/nanoid.cjs" } }, "sha512-N8SpfPUnUp1bK+PMYW8qSWdl9U+wwNWI4QKxOYDy9JAro3WMX7p2OeVRF9v+347pnakNevPmiHhNmZ2HbFA76w=="],
   }
 }

docker-compose.yaml

@@ -65,6 +65,12 @@ services:
       - UPSTASH_REDIS_REST_TOKEN=example_token
       - FREESOUND_CLIENT_ID=${FREESOUND_CLIENT_ID}
       - FREESOUND_API_KEY=${FREESOUND_API_KEY}
+      # Transcription (Optional - leave blank to disable auto-captions)
+      - CLOUDFLARE_ACCOUNT_ID=${CLOUDFLARE_ACCOUNT_ID}
+      - R2_ACCESS_KEY_ID=${R2_ACCESS_KEY_ID}
+      - R2_SECRET_ACCESS_KEY=${R2_SECRET_ACCESS_KEY}
+      - R2_BUCKET_NAME=${R2_BUCKET_NAME}
+      - MODAL_TRANSCRIPTION_URL=${MODAL_TRANSCRIPTION_URL}
     depends_on:
       db:
         condition: service_healthy

package.json

@@ -21,6 +21,7 @@
   },
   "dependencies": {
     "next": "^15.3.4",
+    "react-country-flag": "^3.1.0",
     "wavesurfer.js": "^7.9.8"
   },
   "trustedDependencies": [