Image MIME Reference
AIMG
Universal AI Media Format (Image)
image/prs.aimg
VS
Windows Bitmap (Legacy Windows MIME Alias)
image/x-windows-bmp
BMP
A complete technical comparison of Universal AI Media Format (Image) and Windows Bitmap (Legacy Windows MIME Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
BMP wins on browser support
Feature Support
| Feature | AIMG | BMP |
|---|---|---|
| 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 |
Universal AI Media Format (Image)
image/prs.aimg
Extension
.aimg
Container
Universal AI Media Format (AIMF)
Compression
Container (Inherits payload compression, e.g., PNG/JPEG)
Algorithm
None (Pass-through to embedded payload)
Color Depth
Inherited from payload (8-bit, 16-bit, HDR)
Developed by
AI Media Format (ai-mf) Open-Source Project
Released
2026
Magic Bytes
Varies (Custom AIMF Header Prepended to Payload)
Windows Bitmap (Legacy Windows MIME Alias)
image/x-windows-bmp
Extension
.bmp.dib
Container
DIB (Device-Independent Bitmap)
Compression
Uncompressed / Run-Length Encoding (RLE)
Algorithm
NoneRLE4RLE8
Color Depth
1-bit (Monochrome), 4-bit (16 colors), 8-bit (256 colors), 16-bit (High Color), 24-bit (True Color), 32-bit (True Color with Alpha)
Developed by
Microsoft Corporation
Released
1985
Magic Bytes
42 4D
Browser Support Comparison
| Browser | AIMG | BMP |
|---|---|---|
|
|
✕ |
✓ 1
|
|
|
✕ |
✓ 1
|
|
|
✕ |
✓ 1
|
|
|
✕ |
✓ 12
|
|
|
✕ |
✓
|
AIMG
AIMG Strengths
- Provides a robust, tamper-evident cryptographic wrapper to definitively prove the origin of AI-generated media
- Header-first structure allows verifier nodes and APIs to validate an image's origin without needing to download or decode the entire massive pixel payload
Limitations
- Lacks native rendering support in browsers, requiring server-side extraction or client-side WebAssembly to display the embedded image
- Utilizes the IANA 'prs.' (personal/vanity) tree rather than the standards tree, which can cause strict enterprise firewalls to reject the MIME type as unverified
BMP
BMP Strengths
- Universally supported by all major operating systems and modern web browsers
- Maintains perfect, lossless fidelity because pixel data is stored without lossy compression artifacts
Limitations
- Massive file size overhead due to a lack of modern compression algorithms
- Legacy MIME strings like 'image/x-windows-bmp' can trigger validation warnings in strict security or API environments if unhandled
When to choose which format
AIMG
Use AIMG when…
- AI Provenance and Attribution
- Verifiable Deepfake Prevention
- Cryptographic Media Watermarking
- Generative AI Workflows
BMP
Use BMP when…
- Legacy Windows Desktop Registry Associations
- Older Enterprise Intranet Applications
- Windows Graphics Archival