Generate ad image variations using GPT-4, Dumpling AI & Google Drive

What this workflow does This workflow takes a reference ad image and brand website, then uses GPT-4, LangChain, and Dumpling AI to generate 10 high-quality image variations for ad testing. These image variations are visually consistent but subtly different in background, mood, lighting, and tone — perfect for performance testing on platforms like Meta Ads or TikTok. --- 👤 Who is this for - DTC marketers and brand designers testing ad creatives - Creative teams automating visual experimentation - Content agencies using AI for fast ad mockups - Performance marketers running multivariate testing --- ⚙️ How to set up ✅ Requirements You’ll need the following tools set up in n8n: - Google Drive (OAuth2 credential) - Google Sheets (OAuth2 credential) - OpenAI API (for GPT-4 or GPT-4o) - Dumpling AI API (via HTTP header authentication) --- 🛠️ Steps to configure 1. Google Sheet Setup - Create a sheet with one column: Image URL - Update the Sheet ID and tab name in the final Google Sheets node. 2. Drive Setup - Create a folder in Google Drive for storing the reference image. - Replace the folderId in the “Upload Ad Image to Google Drive” node. 3. Dumpling AI API Key - Use n8n’s credential manager (HTTP Header Auth) — do not hardcode the key. 4. OpenAI API Key - Required for both image description and LangChain agent prompt generation. 5. Form Inputs Required - Brand Name - Brand Website - Ad Image (upload field) --- 🧠 How it works 1. A user submits the brand name, website, and a reference ad image through a form. 2. The image is uploaded to Google Drive. 3. GPT-4o describes the image’s visual style (e.g., mood, lighting, composition). 4. GPT-4 analyzes the brand’s website to define its visual aesthetic. 5. A LangChain agent uses both analyses to create 10 tightly scoped variation prompts. 6. Dumpling AI generates a new image for each prompt using its “FLUX.1-pro” model. 7. Each new image’s link is logged into Google Sheets. --- 🛠️ How to customize - 🧪 Change prompt logic to experiment with different variations (e.g., theme, season). - 🎨 Switch image model in Dumpling AI to one that supports your desired style. - 🔗 Log additional metadata (prompt, timestamp) to Google Sheets. - 📤 Connect output images to Airtable, Notion, or a review tool like Figma. - 🎯 Modify GPT system message to reflect a different tone or brand strategy. --- This workflow gives creative teams and marketers an instant, AI-powered ad image testing system — built on real brand visuals, not generic stock content.