Image MIME Reference
AVIF
AV1 Image File Format
image/avif
VS
DICOM Run-Length Encoding
image/dicom-rle
DICOM-RLE
A complete technical comparison of AV1 Image File Format and DICOM Run-Length Encoding — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
AVIF wins on browser support
Feature Support
| Feature | AVIF | DICOM-RLE |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | Yes | Yes |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | Yes |
| 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
DICOM Run-Length Encoding
image/dicom-rle
Extension
.dcm.dicom
Container
DICOM (PS3.10)
Compression
Lossless (RLE)
Algorithm
Run-Length Encoding (RLE)
Color Depth
8-bit, 16-bit, 24-bit
Developed by
National Electrical Manufacturers Association (NEMA) / ACR
Released
1993
Magic Bytes
44 49 43 4D (at byte offset 128)
Browser Support Comparison
| Browser | AVIF | DICOM-RLE |
|---|---|---|
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
DICOM-RLE
DICOM-RLE Strengths
- Guarantees lossless preservation of critical medical data necessary for diagnostics
- Extremely robust metadata structure containing patient information, modality, and spatial geometry
- Faster to encode and decode than complex compression schemes like JPEG 2000
Limitations
- RLE compression offers very low compression ratios compared to modern codecs like JPEG-LS or JPEG 2000
- Zero support in web browsers or standard consumer image viewers
- Strict data privacy regulations (HIPAA/GDPR) make handling DICOM files complex due to embedded PHI
When to choose which format
AVIF
Use AVIF when…
- Next-Gen Websites
- HDR Photography
- High-Quality Web Images
DICOM-RLE
Use DICOM-RLE when…
- Medical Imaging
- Ultrasound
- X-Rays / CT / MRI
- PACS Archives