Image MIME Reference
Epson-ERF
Epson Raw Format
image/x-epson-erf
VS
Tagged Image File Format (Legacy MIME)
image/x-tiff
TIFF
A complete technical comparison of Epson Raw Format and Tagged Image File Format (Legacy MIME) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Epson-ERF | TIFF |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | ✕ No | Yes |
Epson Raw Format
image/x-epson-erf
Extension
.erf
Container
TIFF/EP
Compression
Uncompressed / Lossless JPEG (ITU-T81)
Algorithm
NoneLossless JPEG
Color Depth
12-bit (Per Channel)
Developed by
Seiko Epson Corporation
Released
2004
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
Tagged Image File Format (Legacy MIME)
image/x-tiff
Extension
.tiff.tif
Container
IFD (Image File Directory) Tag Structure
Compression
Uncompressed / LZW (Lossless) / ZIP / Deflate (Lossless) / PackBits (Lossless RLE) / JPEG (Lossy) / CCITT Group 3/4 (Fax/Document)
Algorithm
NoneLZWDeflatePackBitsJPEGCCITT
Color Depth
1-bit (Monochrome), 8-bit (Grayscale or Indexed), 16-bit (Per Channel), 32-bit (Float Per Channel)
Developed by
Aldus Corporation (Later acquired by Adobe Systems)
Released
1986
Magic Bytes
49 49 2A 00 (Little-endian) or 4D 4D 00 2A (Big-endian)
Browser Support Comparison
| Browser | Epson-ERF | TIFF |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Epson-ERF
Epson-ERF Strengths
- Preserves original raw sensor data, allowing extreme recovery of highlights and shadows compared to in-camera JPEGs
- Utilizes the standard TIFF container structure, making it relatively easy for open-source software (like dcraw and LibRaw) to parse and decode
Limitations
- Completely obsolete proprietary format tied to a defunct line of digital cameras
- Requires parsing EXIF metadata to differentiate it from standard TIFF files programmatically
- Cannot be natively viewed in web browsers or standard operating system image viewers without specialized codecs
TIFF
TIFF Strengths
- Universally accepted as the gold standard for high-fidelity archival and professional print workflows
- Highly adaptable structure supports multiple pages (documents), layers, vast bit depths, and diverse compression algorithms within a single file
- Unmatched support for rich metadata including EXIF, IPTC, XMP, and custom ICC color profiles
Limitations
- Produces exceptionally large file sizes compared to modern web formats
- The 'x-tiff' legacy MIME string forces developers to write extra validation logic to prevent strict security filters from rejecting valid uploads
- The format's immense complexity means that many lightweight parsers only implement a subset of the specification, sometimes failing to read obscure compressions (like CCITT or old JPEG-in-TIFF)
When to choose which format
Epson-ERF
Use Epson-ERF when…
- Vintage Digital Photography (Epson R-D1)
- Non-destructive Image Post-Processing
- Raw Imaging Archival
TIFF
Use TIFF when…
- Professional Print and Desktop Publishing
- High-Resolution Archival Scanning
- Master Copies of Digital Photography