Image MIME Reference
AVCS
AVC Image Sequence (HEIF Container)
image/avcs
VS
DjVu Document
image/vnd.djvu
DjVu
A complete technical comparison of AVC Image Sequence (HEIF Container) and DjVu Document — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | AVCS | DjVu |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | Yes |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
AVC Image Sequence (HEIF Container)
image/avcs
Extension
.avcs.heifs
Container
HEIF / ISOBMFF (ISO/IEC 14496-12)
Compression
Lossy / Lossless
Algorithm
AVC (Advanced Video Coding / H.264)
Color Depth
8-bit, 10-bit, 12-bit
Developed by
Moving Picture Experts Group (MPEG) / ISO/IEC JTC 1
Released
2015
Magic Bytes
XX XX XX XX 66 74 79 70 61 76 63 73
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
Browser Support Comparison
| Browser | AVCS | DjVu |
|---|---|---|
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
AVCS
AVCS Strengths
- Efficiently stores bursts of images or animations utilizing inter-frame compression
- Leverages the highly compatible and widely hardware-accelerated AVC (H.264) codec
- Robust HEIF container supports extensive metadata, alpha channels, and depth maps
Limitations
- Zero native support in web browsers
- Largely superseded in efficiency by newer sequence formats like HEICS (HEVC) or Animated AVIF (AV1)
- Complicated container structure requires specialized parsing libraries
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
When to choose which format
AVCS
Use AVCS when…
- Burst Photography
- Short Animations
- Camera Capture
- Archival Storage
DjVu
Use DjVu when…
- Scanned Books and Manuals
- Digital Libraries (e.g., Internet Archive)
- Historical Document Archiving