Image MIME Reference
DjVu
DjVu Document
image/vnd.djvu
VS
Adobe Photoshop Document
image/vnd.adobe.photoshop
PSD
A complete technical comparison of DjVu Document and Adobe Photoshop Document — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | DjVu | PSD |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | Yes | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
DjVu Document
image/vnd.djvu
Extension
.djvu.djv
Container
Interchange File Format (IFF)
Compression
JB2 (Bi-tonal Text) / IW44 (Wavelet Background) / BZZ (General Data/Text)
Algorithm
JB2IW44BZZ
Color Depth
1-bit (Foreground Text), 24-bit (Background)
Developed by
AT&T Labs (Yann LeCun, Léon Bottou, Patrick Haffner, Paul G. Howard)
Released
1996
Magic Bytes
41 54 26 54 46 4F 52 4D
Adobe Photoshop Document
image/vnd.adobe.photoshop
Extension
.psd.psb.pdd
Container
Adobe Photoshop Document (PSD/PSB)
Compression
Uncompressed / RLE (Run-Length Encoding) / ZIP
Algorithm
RLEZIP (with or without prediction)None
Color Depth
1-bit (Bitmap), 8-bit, 16-bit, 32-bit (Float/HDR)
Developed by
Adobe Systems
Released
1990
Magic Bytes
38 42 50 53
Browser Support Comparison
| Browser | DjVu | PSD |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
DjVu
DjVu Strengths
- Unmatched compression ratios for high-resolution scanned documents (often 5 to 10 times smaller than equivalent JPEG/TIFF-based PDFs)
- Separates text layers cleanly from backgrounds, allowing for highly legible text even at low file sizes
- Embedded OCR (Optical Character Recognition) text layers allow for fast searching
Limitations
- Lacks native support in modern operating systems and web browsers, requiring third-party software
- Largely superseded by PDF/A and modern PDF compression standards in standard corporate workflows
- Not suitable for vector graphics or born-digital documents (like Word exports), where standard PDF is far superior
PSD
PSD Strengths
- The undisputed global standard for layered raster graphics and non-destructive image editing
- Supports incredibly complex compositions combining raster data, vector shapes, live text, and adjustment layers
- Full support for advanced color spaces (CMYK, Lab, multi-channel) and 32-bit floating-point HDR workflows
Limitations
- Proprietary format: while the specification is published, complete feature-parity is rarely achieved by third-party software (e.g., smart objects and complex layer styles often break)
- Files can reach enormous sizes (gigabytes) due to the preservation of unflattened, high-resolution layer data
- Zero support for native rendering in web browsers or standard mobile image viewers
When to choose which format
DjVu
Use DjVu when…
- Scanned Books and Manuals
- Digital Libraries (e.g., Internet Archive)
- Historical Document Archiving
PSD
Use PSD when…
- Professional Photo Retouching
- Digital Painting and Illustration
- UI/UX Design Workflows
- Graphic Design and Print Production