Image MIME Reference
JPEG-LS
JPEG-LS
image/jls
VS
TIFF for Facsimile eXtended
image/tiff-fx
TIFF-FX
A complete technical comparison of JPEG-LS and TIFF for Facsimile eXtended — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | JPEG-LS | TIFF-FX |
|---|---|---|
| Transparency (Alpha) | ✕ No | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | Yes |
JPEG-LS
image/jls
Extension
.jls.jl
Container
JPEG Bitstream
Compression
Lossless / Near-Lossless (Predictive Coding)
Algorithm
LOCO-I (Low Complexity Lossless Compression for Images)Golomb-Rice Coding
Color Depth
8-bit, 12-bit, 16-bit (Per Channel)
Developed by
Joint Photographic Experts Group (ISO/ITU-T) & HP Labs
Released
1999
Magic Bytes
FF D8 FF F7
TIFF for Facsimile eXtended
image/tiff-fx
Extension
.tiff.tif
Container
TIFF 6.0 Tag Directory Structure
Compression
MH / MR / MMR (CCITT Group 3 & 4) / JBIG / JPEG
Algorithm
CCITT Group 3/4JBIGJPEG
Color Depth
1-bit (Monochrome B&W), 8-bit (Grayscale/Color Indexed), 24-bit (RGB Color)
Developed by
IETF (Internet Engineering Task Force)
Released
1998
Magic Bytes
49 49 2A 00 (Little-Endian) / 4D 4D 00 2A (Big-Endian)
Browser Support Comparison
| Browser | JPEG-LS | TIFF-FX |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
JPEG-LS
JPEG-LS Strengths
- Provides state-of-the-art lossless compression ratios for continuous-tone images, often outperforming Lossless JPEG and JPEG 2000
- Extremely fast and computationally inexpensive to encode/decode, requiring no complex floating-point math or DCTs
- Highly resilient in constrained hardware environments, making it ideal for medical equipment and deep-space probes (e.g., Mars rovers)
Limitations
- Zero native support in web browsers or standard consumer operating systems
- Lacks the advanced resolution scalability and progressive decoding features found in JPEG 2000
- Primarily relegated to niche enterprise sectors (healthcare/DICOM and aerospace) rather than consumer adoption
TIFF-FX
TIFF-FX Strengths
- Provides a universal, standardized format for transmitting multi-page documents over IP networks and email (Internet Fax)
- Supports highly efficient telecom-centric compression algorithms (MMR, JBIG) that produce very small files for text documents
- Maintains backwards compatibility with standard TIFF parsers
Limitations
- Not supported natively by web browsers
- Requires complex parsing of TIFF IFD tags to differentiate a true TIFF-FX file from a standard TIFF file
- Usage is slowly declining as traditional faxing is replaced by secure PDF transmission and e-signature platforms
When to choose which format
JPEG-LS
Use JPEG-LS when…
- Medical Imaging (DICOM Encapsulation)
- Space and Planetary Imaging (NASA/ESA)
- Industrial Machine Vision
- Scientific Archival Storage
TIFF-FX
Use TIFF-FX when…
- Internet Fax (T.37)
- Enterprise Fax Servers
- Document Archiving
- Telecommunications