🎬 Extend videos with audio using Fal, OpenAI, and Upload-Post for TikTok

⚡ 141 views · 🎬 Content Creation & Video

💡 Pro Tip — Since TikTok doesn’t have a public API, getting data usually means fragile HTTP scraping. ScraperNode is a community node that gives you clean JSON for TikTok profiles, videos, and comments — drop it into your workflow and skip the parsing.

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Description

Quick overview

This workflow accepts a video URL and prompt, uses Fal.ai (ltx-2.3-quality) to extend the video forward with generated audio, generates an SEO-friendly title with OpenAI, downloads the finished video, and uploads it to TikTok via the Upload-Post API.

How it works

  1. Triggers from either an n8n Form submission or an incoming Webhook request containing video_url and prompt.
  2. Sends the video URL and prompt to Fal.ai’s ltx-2.3-quality extend-video endpoint to start an asynchronous high-quality render with audio generation enabled.
  3. Waits 60 seconds and repeatedly polls Fal.ai’s queue status endpoint until the job status returns COMPLETED.
  4. Fetches the completed Fal.ai request details to retrieve the final generated video URL.
  5. Sends the original prompt to OpenAI (GPT-5) to generate a short, clickable, SEO-oriented video title.
  6. Downloads the generated video file and uploads it to Upload-Post with the generated title, targeting the TikTok platform.

Setup

  1. Add a Fal.run API credential (HTTP Header Auth) and confirm the extend-video and status/request URLs match your Fal.ai account and model.
  2. Add an OpenAI API credential and, if needed, change the model in the title-generation step.
  3. Add an Upload-Post API credential (HTTP Header Auth), set your user value (currently YOUR_USERNAME), and confirm the Upload-Post endpoint and TikTok platform parameter.
  4. If triggering externally, copy the Webhook URL and configure the calling app to send video_url and prompt, or use the included n8n Form to submit those fields.
  5. Adjust the polling delay (60 seconds) if you need faster updates or fewer API calls.

Additional info

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🔗 Nodes Used

HTTP Request, Webhook, n8n Form Trigger, OpenAI

📥 Import

Download workflow.json and import into n8n: Workflow menu → Import from File

📖 Importing guide · 🔑 Credential setup