Free webp to jpg
EN
Image MIME Reference
JNG

JPEG Network Graphics

image/x-jng
VS

JPEG XR Image Sequence (HEIF Container)

image/jxrs
JPEG-XR-Sequence

A complete technical comparison of JPEG Network Graphics and JPEG XR Image Sequence (HEIF Container) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature JNG JPEG-XR-Sequence
Transparency (Alpha) Yes Yes
Animation Support ✕ No Yes
Progressive Loading Yes Yes
HDR Support ✕ No Yes
EXIF Metadata Yes Yes
ICC Color Profile Yes Yes
JPEG Network Graphics
image/x-jng
Extension
.jng
Container PNG-style Chunk Structure (JHDR, JDAT, IDAT, IEND)
Compression Lossy (JPEG/DCT for color) / Lossless (Deflate for alpha mask)
Algorithm
JPEG (Discrete Cosine Transform)Deflate (LZ77)
Color Depth 8-bit, 12-bit, 24-bit (RGB), 32-bit (RGBA)
Developed by MNG Development Group (Glenn Randers-Pehrson et al.)
Released 2001
Magic Bytes
8B 4A 4E 47 0D 0A 1A 0A
Full JNG reference →
JPEG XR Image Sequence (HEIF Container)
image/jxrs
Extension
.jxrs
Container HEIF / ISOBMFF (ISO/IEC 23008-12 / Annex F of ITU-T T.832)
Compression Lossy / Lossless
Algorithm
JPEG XR (Lapped Biorthogonal Transform)
Color Depth 8-bit, 16-bit, 32-bit (Float)
Developed by ISO/IEC JTC 1 / ITU-T
Released 2019
Magic Bytes
XX XX XX XX 66 74 79 70 6A 78 72 53
Full JPEG-XR-Sequence reference →

Browser Support Comparison

Browser JNG JPEG-XR-Sequence
Chrome Chrome
✕ ✕
Firefox Firefox
✕ ✕
Safari Safari
✕ ✕
Edge Edge
✕ ✕
IE IE (Legacy)
✕ ✕
JNG

JNG Strengths

  • Solved a massive technical hurdle in the early 2000s by combining high-compression lossy photographic data with crisp, 8-bit alpha transparency
  • Utilized the highly robust, extensible chunk-based architecture of the PNG format
  • Provided an excellent, bandwidth-saving alternative to massive 32-bit transparent PNGs for web design
Limitations
  • Failed to achieve critical mass; browser vendors largely abandoned the MNG/JNG standard due to implementation complexity
  • Completely obsolete today, having been superseded by natively supported, superior formats like WebP, AVIF, and HEIC
  • Decoding requires a hybrid engine that can parse PNG chunks while simultaneously decoding a JPEG stream and a Deflate stream, complicating software support
JPEG-XR-Sequence

JPEG-XR-Sequence Strengths

  • Supports 32-bit floating point HDR color depths natively across an entire animation sequence
  • Combines the advanced coding efficiencies of JPEG XR with the sequence timing and metadata framework of HEIF
  • Shares frame data structures allowing for optimized storage of burst photography
Limitations
  • Extremely rare format with essentially no mainstream software adoption
  • Zero web browser support
  • Overshadowed heavily by HEVC (HEIC sequences) and AV1 (AVIF sequences) which offer superior compression and broader hardware decoding support

When to choose which format

JNG
Use JNG when…
  • Embedded frames in MNG animations
  • Historical web graphics requiring lossy compression with transparency
JPEG-XR-Sequence
Use JPEG-XR-Sequence when…
  • Experimental Animation Workflows
  • HDR Burst Photography Archiving
  • Specialized Medical & Scientific Imaging

More comparisons

JNG vs ACES → JPEG-XR-Sequence vs ACES → JNG vs APNG → JPEG-XR-Sequence vs APNG → JNG vs AVCI → JPEG-XR-Sequence vs AVCI → JNG vs AVCS → JPEG-XR-Sequence vs AVCS → JNG vs AVIF → JPEG-XR-Sequence vs AVIF → All comparisons →
Share this comparison