Auto-Caption Videos from Google Drive using ZapCap - n8n Workflow

• Content Creators who frequently need accurate subtitles for social media videos.


• Marketing Teams looking to accelerate video production workflows.


• n8n users seeking advanced cloud storage and AI integration n8n templates.


• Anyone aiming to automate repetitive video post-production tasks using n8n.

Manually adding subtitles to videos is a time-consuming and often repetitive task. This efficient n8n workflow completely eliminates that manual effort. By integrating Google Drive with the specialized AI video captioning service, ZapCap, users can achieve hands-free video processing. When a video is uploaded to a designated Google Drive folder, this n8n automation immediately triggers the captioning process, monitors its completion status, and automatically uploads the professionally captioned video back to your drive. Leveraging this n8n template helps content creators save hours, speed up their content pipeline, and ensure accessibility across all video platforms.

This comprehensive n8n workflow operates as follows:

1. Triggering the Flow: The process begins with the Google Drive Trigger n8n trigger. It constantly watches a specific, configured folder in Google Drive for new file uploads.


2. Uploading to ZapCap: Once a new video file is detected, the workflow uses an HTTP Request n8n node to submit the publicly accessible video URL (webViewLink) to the ZapCap API for initial upload.


3. Starting Processing: A subsequent HTTP Request n8n node sends a POST request to ZapCap, triggering the AI captioning task using a specified templateId and enabling auto-approval.


4. Polling for Status: The workflow uses a polling mechanism to check the job status. The 'Get processing task' HTTP Request n8n node periodically queries the ZapCap API for the task status.


5. Conditional Check: The 'If processing completed' n8n node checks if the status is either completed or failed. If the status is not yet final, the flow routes through the 'Wait' n8n node, creating a delay before polling the status again. This loop continues until the video is processed.


6. Downloading the Result: If the status is completed, the workflow executes the 'Download completed video' HTTP Request n8n node, retrieving the final, captioned video file using the provided downloadUrl.


7. Final Upload: The last n8n node, 'Upload file' (Google Drive), saves the finalized, captioned video back to a configured folder in Google Drive, making it immediately available for distribution.

To deploy this powerful n8n workflow, follow these setup steps:

1. Import the n8n Workflow: Copy the provided JSON data and paste it into your n8n instance (n8n Cloud or self-hosted) using the 'New' -> 'Import from JSON' option.


2. Google Drive Credentials: Configure the Google Drive credentials for both the Google Drive Trigger and the Google Drive 'Upload file' n8n node. This typically requires OAuth2 setup.


3. Configure Google Drive Folders: In the Google Drive Trigger, specify the source folder ID where new videos will be uploaded. In the final Google Drive n8n node ('Upload file'), specify the destination folder ID for the captioned videos. Note: Use separate source and destination folders to prevent workflow loops or file clashes.


4. ZapCap API Key: ZapCap requires API Key authentication. Create a Generic Credential in n8n for 'HTTP Header Auth'. The header name must be set to x-api-key, and the value should be your ZapCap API key (obtainable from their dashboard).


5. Activate the n8n Workflow: Ensure all credentials are set and the workflow is active. Upload a test video to your source Google Drive folder to verify the n8n trigger fires correctly.

This n8n workflow utilizes several key nodes to manage the automated video captioning process:

Google Drive Trigger (n8n trigger): Initiates the flow upon fileCreated event within a specified Google Drive folder. This is the entry point for the entire n8n automation.
Upload video to ZapCap (HTTP Request n8n node): Sends a POST request to the ZapCap API, providing the webViewLink of the newly uploaded file, essential for ZapCap to access the video. Uses Generic HTTP Header Authentication.
Trigger video processing (HTTP Request n8n node): Sends the command to start the AI processing task for the uploaded video, configuring the job with a specific templateId.
Get processing task (HTTP Request n8n node): Used within the polling loop to retrieve the current status of the AI captioning task using the video ID and task ID.
If processing completed (If n8n node): A core logic component that checks if the task status is either completed or failed. If the task is incomplete, it routes the execution to the Wait n8n node for polling.
Wait (n8n node): Implements a delay mechanism when polling is necessary, ensuring the n8n workflow doesn't overwhelm the API while waiting for processing completion.
Download completed video (HTTP Request n8n node): Downloads the resulting captioned video file from the downloadUrl provided by ZapCap upon completion.
Upload file (Google Drive n8n node): The final action, which saves the downloaded captioned video back into the designated Google Drive destination folder, completing the n8n workflow cycle.