AgentReel 如何用 AI B-Roll Cut 自動剪輯 B-roll 影片

Every creator who makes explainer videos knows the worst part of the job. The script is written. The voiceover is recorded. Then come three or four hours of scrubbing through clips, dragging a shot under every sentence, trimming, and adding captions one line at a time.

I built AgentReel to remove that work. This post walks through every main feature, and spends the most time on the one I am proudest of: AI B-Roll Cut.

AI B-Roll Cut: paste a script, get a finished edit

AI B-Roll Cut takes two inputs: your footage and your voiceover script. It returns one rendered MP4 with the voiceover and burned-in captions.

Here is the flow:

Upload your clips. Up to 500 videos (.mp4, .mov, .m4v) or photos. Each photo becomes a 4-second clip with a slow zoom. Heavy 4K phone footage is compressed in your browser to a light 1080p copy before upload.
Paste the script. English or Chinese, up to about 8 minutes of speech. The script is split into caption-sized phrases, with a time for every word.
AI matches the footage. The AI looks at every clip once and notes what it shows, the shot size, how steady the camera is, and which scene it belongs to. Then it plans the B-roll beat by beat against the story.
Render and download. Check the timeline phrase by phrase, pick 16:9 or 9:16, and render.

Why this is different: code to video

Most AI video tools generate pixels. B-Roll Cut does something else. The AI only makes the creative decision: which shot goes under which phrase. A fixed, deterministic assembler then does the cutting, in code, on a 30 fps grid.

That split matters:

Every cut lands on a frame. No drifting audio, no half-frame flashes.
No clip repeats too soon. The assembler uses an unused second of footage before it repeats one, and a clip never follows itself.
The pace is yours. Choose fast, medium, or slow, with shots of about 1.5 to 4 seconds.
The timeline is readable. Every phrase lists its shots with the clip name, the source time, and the length.
Captions are built in. Pick from several caption styles, from a classic dark box to a thick outline, and they are burned into the render.

This is what I mean by "code to video." The model plans, the code edits, and the result is the same every time you render it. For a YouTube explainer, a product launch video, or a 9:16 short that viewers watch on mute, it turns hours of manual editing into minutes.

AI Video Generator: 20 video models behind one prompt box

The AI Video Generator puts the top video models side by side: Seedance, Kling, Wan, Veo, MiniMax, Grok Imagine and more. Type a prompt or upload a photo, pick a model, and get a clip.

Each model has its own strengths. Some handle camera moves and multi-shot scenes well, some give natural human motion, and some excel at surreal close-ups. With one prompt box you can run the same idea through two models and keep the better result.

AI Image Generator: 20 image models

The AI Image Generator covers Nano Banana, GPT Image, Seedream, Z-Image and others. Use it for product shots, thumbnails, covers, and the first frame of a video.

AI Video Ad Generator

The AI Video Ad Generator makes short promos for a product page or a social feed, so a small brand can test several ad ideas without a production budget.

TikTok Carousel Maker

The TikTok Carousel Maker builds slide posts with one consistent style across every slide, ready for TikTok and Instagram.

Video Templates

Video Templates give you a ready-made format to start from. Swap in your own content and render. This is the fastest way to try AgentReel, and a free account can use it.

Free browser tools

AgentReel also has a set of free tools for everyday jobs: enhance and upscale, background removal, convert and compress, crop and split.

Pricing, plainly

Every tool shows its credit cost before a job starts.
A failed job refunds its credits automatically.
A daily check-in gives 15 free credits. Free credits work with the Z-Image model and video templates.
Premium models and B-Roll Cut use purchased credits. It is pay as you go, with no monthly lock-in.

There is nothing to install. Everything runs in the browser.

Try it

If you make talking-head or voiceover videos, start with AI B-Roll Cut. If you only want to see what the models can do, start with a free video template. Everything else is at agentreel.co.