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How to Programmatically Add Text Overlay Captions to Videos with FFMPEGAPI.net

June 2026 FFMPEG API Team

In today's digital world, adding text overlays to videos can significantly enhance viewer engagement and clarity. Whether you're creating educational content, marketing videos, or social media posts, the ability to programmatically add captions is invaluable. FFMPEGAPI.net offers a powerful REST API that simplifies this process, enabling developers to integrate text overlays easily without managing server infrastructure.

Why Use FFMPEGAPI.net for Text Overlays?

FFMPEGAPI.net is designed for developers who need a robust solution for audio and video processing. By leveraging this hosted API, you can focus on building your application without the hassles of server setup or FFmpeg management. The API-key authentication also ensures secure access to your workflows.

  • No server setup required.
  • Quick integration with simple API endpoints.
  • Flexible options for text overlay customization.

Using the Text Overlay Captions Endpoint

The 'Text Overlay Captions' endpoint allows you to render supplied text lines directly onto your video. This feature is useful for adding informative captions that can help viewers follow your content more easily. The endpoint's flexibility lets you specify the appearance and timing of the captions.

You can access the endpoint via a POST request to /api/videos/add-text-overlay-captions, where you will need to provide the video URL and the text you want to overlay.

  • Endpoint: POST /api/videos/add-text-overlay-captions
  • Supports multiple customization parameters.
  • Ideal for enhancing the accessibility of your videos.
curl -X POST https://ffmpegapi.net/api/videos/add-text-overlay-captions \
-H 'Content-Type: application/json' \
-d '{ \
  "video_url": "https://example.com/video.mp4", \
  "text": "First line\nSecond line", \
  "duration_per_line": 4 \
}'
import requests\n\nurl = 'https://ffmpegapi.net/api/videos/add-text-overlay-captions'\ndata = {\n    'video_url': 'https://example.com/video.mp4',\n    'text': 'First line\nSecond line',\n    'duration_per_line': 4\n}\n\nresponse = requests.post(url, json=data)\nprint(response.json())

Customizing Your Captions

FFMPEGAPI.net allows you to customize several aspects of your text overlays, including the style, position, and timing. You can choose from various subtitle styles such as plain-white or colored backgrounds, and adjust the aspect ratio to fit your video format.

These options provide a tailored experience, ensuring that your captions appear exactly as you envision.

  • Subtitle Styles: plain-white, yellow-bg, pink-bg, etc.
  • Positioning: top, center, or bottom of the video.
  • Aspect Ratios: 16:9, 9:16, 4:3, or 3:4.

Integrating text overlay captions into your video processing workflow has never been easier thanks to FFMPEGAPI.net. With its user-friendly API, developers can enhance video content programmatically without the burden of managing infrastructure. Whether for educational purposes, marketing, or accessibility, FFMPEGAPI.net is the best choice for merging your video workflows with powerful text overlay capabilities.

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