Image MIME Reference
AVIF
AV1 Image File Format
image/avif
VS
Computer Graphics Metafile
image/cgm
CGM
A complete technical comparison of AV1 Image File Format and Computer Graphics Metafile — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
AVIF wins on browser support
Feature Support
| Feature | AVIF | CGM |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | Yes |
AV1 Image File Format
image/avif
Extension
.avif
Container
HEIF / ISOBMFF
Compression
AV1 Lossy / AV1 Lossless
Algorithm
AV1
Color Depth
8-bit, 10-bit, 12-bit
Developed by
Alliance for Open Media (AOMedia)
Released
2019
Magic Bytes
XX XX XX XX 66 74 79 70 61 76 69 66
Computer Graphics Metafile
image/cgm
Extension
.cgm
Container
CGM
Compression
Uncompressed / Binary / Character / Clear Text
Algorithm
Deflate (in some WebCGM profiles)
Color Depth
8-bit, 16-bit, 24-bit, 32-bit
Developed by
ISO / IEC
Released
1987
Magic Bytes
00 20 (Binary) / 42 45 47 49 4E 20 4D 45 54 41 46 49 4C 45 (Clear Text)
Browser Support Comparison
| Browser | AVIF | CGM |
|---|---|---|
Chrome
|
✓ 85+
|
✕ |
Firefox
|
✓ 93+
|
✕ |
Safari
|
✓ 16+
|
✕ |
Edge
|
✓ 121+
|
✕ |
IE (Legacy)
|
✕ | ✕ |
AVIF
AVIF Strengths
- Best-in-class compression — typically 20–50% smaller than WebP at equivalent quality
- Native HDR and wide color gamut (BT.2020) support
- Supports 8, 10, and 12-bit color depth
Limitations
- Encoding is highly CPU-intensive — significantly slower than JPEG or WebP
- Requires Edge 121+ (not supported in earlier Edge versions)
- Limited support in native desktop image viewers
CGM
CGM Strengths
- Strictly standardized by ISO, ensuring long-term archiving and cross-platform compatibility in engineering
- Excellent support for rich metadata, hyperlinks, and technical hotspots via the WebCGM profile
- Can store complex 2D geometry, rasters, and text in a single lightweight file
Limitations
- Multiple encoding schemes (Binary, Character, Clear Text) make parser development difficult
- Zero native support in modern web browsers without third-party plugins
- Largely replaced by SVG for general-purpose 2D vector graphics on the web
When to choose which format
AVIF
Use AVIF when…
- Next-Gen Websites
- HDR Photography
- High-Quality Web Images
CGM
Use CGM when…
- Technical Illustrations
- Aerospace & Defense (S1000D)
- CAD/CAM
- Geophysics