Image MIME Reference
HTJ2K-Codestream
High-Throughput JPEG 2000 Codestream
image/jphc
VS
Sony Alpha Raw Image
image/x-sony-arw
Sony-ARW
A complete technical comparison of High-Throughput JPEG 2000 Codestream and Sony Alpha Raw Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | HTJ2K-Codestream | Sony-ARW |
|---|---|---|
| Transparency (Alpha) | Yes | ✕ No |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
High-Throughput JPEG 2000 Codestream
image/jphc
Extension
.jhc
Container
None (Raw Codestream)
Compression
Lossy / Lossless
Algorithm
High-Throughput JPEG 2000 (HTJ2K)
Color Depth
8-bit, 16-bit, 32-bit, 38-bit
Developed by
Joint Photographic Experts Group (JPEG)
Released
2019
Magic Bytes
FF 4F FF 51
Sony Alpha Raw Image
image/x-sony-arw
Extension
.arw
Container
TIFF-based (Proprietary)
Compression
Uncompressed / Lossless Compressed / Lossy Compressed
Algorithm
NoneSony Proprietary LosslessSony Proprietary Lossy
Color Depth
12-bit (Per Channel), 14-bit (Per Channel)
Developed by
Sony Corporation
Released
2006
Magic Bytes
49 49 2A 00
Browser Support Comparison
| Browser | HTJ2K-Codestream | Sony-ARW |
|---|---|---|
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|
✕ | ✕ |
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✕ | ✕ |
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|
✕ | ✕ |
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|
✕ | ✕ |
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|
✕ | ✕ |
HTJ2K-Codestream
HTJ2K-Codestream Strengths
- Extremely fast encoding and decoding capabilities due to the parallelizable block coder
- Minimal file overhead since it lacks container headers and metadata
- Ideal for streaming applications or embedded systems where parsing a full container is unnecessary
Limitations
- Lacks standard metadata support (like EXIF, XMP, or ICC color profiles) since there is no container structure
- Zero native web browser compatibility
- Difficult to distinguish from standard JPEG 2000 codestreams without deeply parsing the internal marker segments
Sony-ARW
Sony-ARW Strengths
- Retains absolute maximum sensor data, enabling massive shadow recovery and highlight protection compared to compressed in-camera JPEGs
- Embeds high-quality JPEG previews and robust metadata, allowing photographers to match in-camera color science (like Creative Looks) perfectly during raw processing
- Utilizes the standard TIFF container structure, ensuring broad compatibility with open-source decoding libraries (like LibRaw)
Limitations
- Proprietary format means it requires constant updates to raw processing engines every time Sony releases a new camera model
- Sony's historically controversial lossy compression algorithm (often called 'star eater' due to spatial filtering artifacts) was a drawback for astrophotography in older ARW versions, though largely resolved in newer models with uncompressed/lossless options
- Cannot be directly embedded into web pages or used in standard HTML/CSS contexts
When to choose which format
HTJ2K-Codestream
Use HTJ2K-Codestream when…
- Medical Imaging Pipelines
- Geospatial Data Streaming
- Digital Cinema
- Embedded Systems
Sony-ARW
Use Sony-ARW when…
- Professional Digital Photography
- Non-destructive Image Post-Processing
- High Dynamic Range (HDR) Imaging Archival