01
Keep the frame connected
As the dialogue grows, the background extends line by line so the image still feels like one continuous scene.
Product overview
Cinematic Subtitle Long Image Generator · Local Canvas
Shadow Snap
v1.3.5 Pure Frontend
Turn an ordinary image into a scene worth sharing
When a line deserves more than a screenshot, upload the image and type the words. Shadow Snap connects subtitles to the frame and exports a cinematic long image you can save or post.
01 / The outcome
How it helps
02
Write first; let the layout follow
Press Enter to add lines. Chinese, English, and other supported scripts are centered and ready to export.
03
Add a signature when you share
Place your own watermark and tune its size, color, position, and opacity before saving.
04
Keep the image in your browser
Your image and words are processed locally, so you can make a draft without sending the original to a server.
02 / Use cases
Use Cases
01
When you want to share a line
Turn a film quote, book excerpt, or your own words into a post that carries the scene with it.
02
When a promo needs atmosphere
Build a first cinematic asset from a still and a few lines without opening a full design suite.
03
When a photo needs a voice
Add a little dialogue to travel, daily-life, or creative images so they say more than they show.
06 / Questions
Frequently Asked Questions
Clear answers regarding features, compatibility, and privacy
How does Shadow Snap generate cinematic subtitle long-images?
Shadow Snap utilizes a proprietary "background-cutting" slicing algorithm that preserves the primary visual framing of the first image while seamlessly stitching subsequent subtitle slices underneath, recreating the authentic narrative rhythm of cinema stills.
Are my images uploaded to a cloud server? Is there any privacy risk?
Zero cloud upload. Shadow Snap runs 100% locally in your browser using the HTML5 Canvas API. All image slicing, text rendering, and image generation happen entirely in your local device memory without sending any byte over the network.
Does it support multi-line subtitles and custom watermarks?
Yes. It supports multi-line text with automatic centering, customizable spacing and fonts, as well as personalized text or graphic watermarks with adjustable opacity and placement for copyright protection.
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