How to Use AI for Video Editing: Descript, Captions, and AI-Powered Post-Production

AI video editing tools can reduce editing time by 50-80% for certain types of content — especially talking head videos, podcasts, and educational content. This guide covers the best tools and workflows.

Descript: Transcript-Based Editing

Descript is the most transformative tool for video editors working with spoken word content. You edit the transcript, and the video edits automatically.

Setup

Upload video to Descript
It transcribes automatically (99%+ accuracy with good audio)
Edit text like a document → video updates to match

Core Workflows

Remove filler words:

Click Edit → Filler Words
Select which words to remove (um, uh, like, you know)
Descript removes them from video and audio automatically

Remove silence:

Go to Edit → Remove Silence
Adjust threshold and minimum gap length
Preview, then apply

Cut by editing text:

Select text in the transcript
Press Delete — that portion of video is cut
Cuts are non-destructive (easily undone)

Fix stumbles without re-recording:

Use Overdub (Descript’s voice cloning feature)
Record your voice once to create a voice clone
Correct mispronounced words or add new sentences

Captions and Subtitles

Auto-Caption Tools

Submagic: Best for social media — auto-captions with animations, emoji, word highlighting. Optimized for viral formats.

CapCut AI: Auto-captions with stylized formatting. Great for TikTok/Reels workflow.

Adobe Premiere Auto-Transcribe: Integrated into Premiere. Good for professional workflows.

YouTube Studio: Free for YouTube uploads — auto-captions that you can edit.

Caption Best Practices

For social media captions:
- Font size: Large (viewers are on mobile)
- Color: High contrast (white text with dark outline)
- Word highlighting: Highlight the current word being spoken
- Emoji: 1-2 relevant emojis per key statement
- Position: Center or slightly above center (not at the very bottom)
- Duration: Display 5-8 words max per screen at a time

AI-Powered B-Roll

Finding Stock Footage with AI

Pexels + AI search: Describe what you need in natural language. Example: “confident businesswoman walking through modern office”

Storyblocks AI: AI-assisted search through their library. Good for corporate/business content.

Runway Gen-3: Generate custom B-roll that doesn’t exist in stock libraries.

Generating Custom B-Roll

For highly specific B-roll that stock can’t provide:

[In Runway Gen-3]

Prompt: Low angle shot, close-up of hands typing on a keyboard, 
modern workspace, blue and white color palette, cinematic, 
depth of field, 5 seconds

Use for: tech content, productivity videos, tutorial overlays

Background Removal and Virtual Sets

Remove Background from Video

Descript: Built-in background removal for any clip

Runway Remove BG: Upload video, background removed in 1-2 minutes

Zoom/Teams virtual background: Real-time background replacement (use blur + subtle virtual set for professional look)

Tips for good background removal:

Solid or non-cluttered backgrounds work better
Good lighting on subject, distinct from background
Wear colors that contrast with your background

Replacing Backgrounds

After removal, add:

Solid color (clean, minimal look)
Office/workspace background
Your branded background (custom branded frame)
Subtle motion background (adds energy without distraction)

Podcast Editing with AI

Adobe Podcast (free): Upload any audio/video, enhance the speech quality automatically. Removes background noise, room reverb, and microphone quality issues. Remarkable results from poor-quality recordings.

Cleanvoice.ai: Removes filler words, background noise, and mouth clicks automatically from audio.

Auphonic: Automatic audio normalization, noise reduction, and loudness correction for podcasts.

Workflow for Podcast-to-Video

Record: Any decent USB mic or phone
Adobe Podcast Enhance: Upload for automatic audio cleanup
Descript: Import for transcript editing, cut tangents and filler
Add captions: Export to Submagic or CapCut for social clips
Create audiogram: Descript’s audiogram feature creates social-friendly clips with waveform visualization

AI Color Grading

DaVinci Resolve (Magic Mask + Color AI): Industry standard, free tier. Magic Mask uses AI to select subjects for isolated color work. Color Warper uses AI-assisted grading.

VEGAS Post (Color Match): AI-powered color matching between clips for consistency.

Topaz Video AI: AI-powered color grading, upscaling, and noise reduction.

Quick Color Grade Workflow (DaVinci Resolve)

Apply a LUT (Look Up Table) as a base — many free LUTs available
Balance exposure with Lift, Gamma, Gain
Use Color Match to match skin tones across clips
Add a Color Warper node for mood/style

Opus Clip

Opus Clip automatically finds the best moments in long videos and creates vertical clips.

Upload a YouTube URL or video file
Select clip types (viral moments, educational, storytelling)
Opus Clip generates 5-10 clips with titles and highlights
Edit and download

Best results:

Long-form content (60+ minutes works well)
Clear speech with distinct points
Minimal background music (can interfere with AI)

For finding the best clips manually:

Upload video to Claude/ChatGPT [with transcript]
Prompt: "Identify the 5 most shareable moments in this video. 
For each, note the timestamp, what makes it shareable (interesting claim, 
surprising fact, emotional moment, actionable advice), and suggest a caption."

Then: cut those clips in your editor and add captions.

Export Settings by Platform

Platform	Resolution	Aspect Ratio	Max Length
YouTube	1080p or 4K	16:9	12 hours
TikTok	1080p	9:16	10 minutes
Instagram Reels	1080p	9:16	90 seconds
LinkedIn	1080p	16:9 or 1:1	10 minutes
Twitter/X	1080p	16:9 or 1:1	2 minutes 20 sec
YouTube Shorts	1080p	9:16	60 seconds