Free webp to jpg
Image MIME Reference
Sony-ARW

Sony Alpha Raw Image

image/x-sony-arw
VS

X Pixmap

image/x-xpixmap
XPM

A complete technical comparison of Sony Alpha Raw Image and X Pixmap — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature Sony-ARW XPM
Transparency (Alpha) ✕ No Yes
Animation Support ✕ No ✕ No
Progressive Loading ✕ No ✕ No
HDR Support Yes ✕ No
EXIF Metadata Yes ✕ No
ICC Color Profile Yes ✕ No
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
Full Sony-ARW reference →
X Pixmap
image/x-xpixmap
Extension
.xpm
Container C Source Code Header (.c / .h)
Compression Uncompressed (Source Code)
Algorithm
None
Color Depth Indexed Color (Custom Palette with RGB and Alpha 'None')
Developed by Daniel Dardailler and Colas Nahaboo (Bull / X Consortium)
Released 1989
Magic Bytes
2F 2A 20 58 50 4D 20 2A 2F (ASCII '/* XPM */')
Full XPM reference →

Browser Support Comparison

Browser Sony-ARW XPM
Chrome Chrome
Firefox Firefox
Safari Safari
Edge Edge
IE IE (Legacy)
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
XPM

XPM Strengths

  • Can be compiled directly into C or C++ source code without requiring an external asset loading mechanism
  • Human-readable palette mapping allows developers to inspect, modify, or hand-craft icons directly within a text editor
  • Native support for color palettes and transparency via the 'None' keyword
Limitations
  • Extremely inefficient storage structure for large images, resulting in massive file bloat compared to binary formats like PNG
  • Completely obsolete and unsupported in modern web browsers
  • Parsing overhead requires compiling or interpreting text-based color tables at runtime

When to choose which format

Sony-ARW
Use Sony-ARW when…
  • Professional Digital Photography
  • Non-destructive Image Post-Processing
  • High Dynamic Range (HDR) Imaging Archival
XPM
Use XPM when…
  • X Window System (X11) Application Icons and Cursors
  • Embedded C/C++ Firmware Color UI Assets
  • Early Linux Desktop Environment Themes
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