Ani-ST vs JXL Format Comparison
Ani-ST
Ani ST Animation Script
image/x-ani-st
VS
JPEG XL
image/jxl
JXL
A complete technical comparison of Ani ST Animation Script and JPEG XL — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
JXL wins on browser support
Feature Support
| Feature | Ani-ST | JXL |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | Yes | Yes |
| Progressive Loading | ✕ No | Yes |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
Ani ST Animation Script
image/x-ani-st
Extension
.scr.str
Container
Text-based Scripting Language
Compression
Uncompressed (Plain Text Script)
Algorithm
None
Color Depth
Atari ST Indexed Palette (up to 16 colors)
Developed by
Jim Kent (Published by Antic Software)
Released
1987
Magic Bytes
JPEG XL
image/jxl
Extension
.jxl
Container
ISOBMFF / JPEG XL Codestream
Compression
Lossy (VarDCT) / Lossless (Modular)
Algorithm
VarDCT (Variable block-size DCT)Modular (Predictive coding for lossless)
Color Depth
8-bit, 10-bit, 12-bit, 16-bit, 32-bit (Float)
Developed by
Joint Photographic Experts Group (JPEG)
Released
2021
Magic Bytes
FF 0A (Codestream) / 00 00 00 0C 4A 58 4C 20 0D 0A 87 0A (Container)
Browser Support Comparison
| Browser | Ani-ST | JXL |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ |
✓ 17+
|
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Ani-ST
Ani-ST Strengths
- 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
Limitations
- 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
JXL
JXL Strengths
- Capable of losslessly recompressing legacy JPEG files, saving ~20% space while retaining perfect byte-for-byte restorability
- Highly superior progressive decoding (Saliency-driven), allowing recognizable images to load extremely fast on slow connections
- Outperforms WebP and competes favorably with AVIF, especially at high-fidelity settings and for complex textures/photography
- Royalty-free with an open-source reference implementation (libjxl)
Limitations
- Google's removal of JXL support from Chrome severely hindered its adoption as a universal web standard
- Lack of hardware decoding chips compared to video-derived codecs like AVIF (AV1)
- File parsing logic is complex due to the split between raw codestreams and ISOBMFF containers
When to choose which format
Ani-ST
Use Ani-ST when…
- Atari ST Retrocomputing Archival
- Vector Animation Scripts
- 1980s Computer Graphics History
JXL
Use JXL when…
- High-End Web Delivery (via Safari/Polyfills)
- HDR Photography
- Legacy JPEG Archiving
- Digital Art & Image Storage
Convert & Edit Online
Free online web tools for Ani-ST and JXL files.
Free Image Resizer
Editor
Resize, scale, crop, and modify dimensions for any photo or graphic.
Use Tool
Image Metadata Remover
Privacy
Clean EXIF, camera, lens, and location tags from your photos.
Use Tool
WebP to JPG Converter
Universal
Convert modern web images to universal high-compatibility JPG.
Use Tool
Compress WebP Images
Optimizer
Reduce image file sizes for faster web performance.
Use Tool