Free webp to jpg
Image MIME Reference
BMP

Windows Bitmap (Legacy Windows MIME Alias)

image/x-windows-bmp
VS

Digital Picture Exchange

image/dpx
DPX

A complete technical comparison of Windows Bitmap (Legacy Windows MIME Alias) and Digital Picture Exchange — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

BMP wins on browser support

Feature Support

Feature BMP DPX
Transparency (Alpha) Yes Yes
Animation Support ✕ No ✕ No
Progressive Loading ✕ No ✕ No
HDR Support ✕ No Yes
EXIF Metadata ✕ No ✕ No
ICC Color Profile Yes ✕ No
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
Full BMP reference →
Digital Picture Exchange
image/dpx
Extension
.dpx
Container DPX (SMPTE ST 268)
Compression Uncompressed / RLE (Rarely used)
Algorithm
Uncompressed
Color Depth 8-bit, 10-bit, 12-bit, 16-bit, 32-bit (Float)
Developed by SMPTE (Society of Motion Picture and Television Engineers)
Released 1994
Magic Bytes
53 44 50 58 (Big-endian) / 58 50 44 53 (Little-endian)
Full DPX reference →

Browser Support Comparison

Browser BMP DPX
Chrome Chrome
✓ 1
Firefox Firefox
✓ 1
Safari Safari
✓ 1
Edge Edge
✓ 12
IE IE (Legacy)
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
DPX

DPX Strengths

  • Industry standard for transferring uncompressed, high-fidelity film and VFX data
  • Rich industry-specific metadata including timecode, keykode, and film stock information
  • Supports logarithmic color spaces (LogC, Cineon) to preserve the massive dynamic range of film negatives
Limitations
  • Massive file sizes (e.g., a single 4K 10-bit frame is ~50MB, resulting in ~1.2GB per second at 24fps)
  • Zero native support in web browsers or consumer OS image viewers
  • Requires heavy-duty, fast storage infrastructure (RAID/NVMe) to playback in real-time

When to choose which format

BMP
Use BMP when…
  • Legacy Windows Desktop Registry Associations
  • Older Enterprise Intranet Applications
  • Windows Graphics Archival
DPX
Use DPX when…
  • Film Scanning
  • Visual Effects (VFX)
  • Digital Intermediate (DI)
  • Color Grading
  • Archival
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