Ani ST Animation Script MIME Type Reference
image/x-ani-st
Released 1987
· by Jim Kent (Published by Antic Software)
The Ani ST format is a legacy animation scripting language and vector graphics format developed in 1987 by Jim Kent for the Atari ST computer. Unlike traditional raster animations that store pixel grids frame-by-frame, Ani ST files are human-readable, plain-text files containing vector commands. These scripts instruct the software how to generate geometric polygons, apply color palettes, and calculate morphing sequences to produce animations. It is completely obsolete and primarily encountered today in retrocomputing archival contexts.
Technical Specifications
.scr.str
None
text/plain
Magic Bytes & HTTP Headers
Browser Support Matrix
| Browser | Status | Min Version |
|---|---|---|
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Not Supported | — |
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Not Supported | — |
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Not Supported | — |
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Not Supported | — |
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Not Supported | Legacy |
Advantages & Limitations
- Produced incredibly small file sizes by storing rendering instructions (vectors) rather than raw raster frames, making it ideal for floppy disks
- The human-readable script format allowed advanced users to manually edit animation paths and parameters directly in a text editor
- Completely obsolete and inherently tied to the hardware limitations of the Atari ST ecosystem
- The generic .scr and .str extensions conflict with dozens of other historical and modern formats, making file identification a major challenge
- Zero native support in modern operating systems, web browsers, or standard graphics software
Developer Code Snippets
File Detection Steps
How to programmatically detect a image/x-ani-st
file by reading its raw bytes:
- 1 Ani ST files lack a binary magic number because they are plain-text ASCII files containing custom vector animation scripting commands.
- 2 Programmatic detection requires parsing the text file for specific Ani ST command syntax rather than relying on standard magic byte libraries.
- 3 MIME sniffing strictly by extension (.scr or .str) is notoriously unreliable and will likely misidentify the file as a Windows Screensaver or dBASE structure.
Software Support
Free Online Tools for Ani-ST
Resize, scale, crop, and modify dimensions for any photo or graphic.
Clean EXIF, camera, lens, and location tags from your photos.
Convert modern web images to universal high-compatibility JPG.
Reduce image file sizes for faster web performance.
Ani-ST Format Comparisons
Share & Embed
[](https://freewebptojpg.com/mime/image/ani-st)
<iframe src="https://freewebptojpg.com/mime/image/ani-st/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="Ani-ST Specs"></iframe>
JSON API
All data on this page is available as a free, open JSON API. Use it in your project, documentation, or tooling.
GET https://freewebptojpg.com/mime/image/ani-st.json
Open JSON
Frequently Asked Questions
What is the magic byte for image/x-ani-st?
Because Ani ST files are human-readable plain-text scripts containing vector commands, they do not possess a binary magic number or fixed hexadecimal signature.
Is image/x-ani-st supported in modern web browsers?
No. Ani ST is an obsolete, platform-specific scripting format from 1987. Modern browsers cannot parse or render its custom Atari ST vector commands.
Why does my Ani ST file have a .scr or .str extension?
Ani ST used .scr (script) and .str (string/structure) for its human-readable animation files. These extensions are highly generic and conflict heavily with Windows Screensavers (.scr) and dBASE structure files (.str).