Free webp to jpg
EN
Image MIME Reference
APNG

Animated Portable Network Graphics

image/vnd.mozilla.apng
VS

JPEG XS Codestream

image/jxsc
JPEG-XS-Codestream

A complete technical comparison of Animated Portable Network Graphics and JPEG XS Codestream — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

APNG wins on browser support

Feature Support

Feature APNG JPEG-XS-Codestream
Transparency (Alpha) Yes Yes
Animation Support Yes ✕ No
Progressive Loading Yes ✕ No
HDR Support ✕ No Yes
EXIF Metadata Yes ✕ No
ICC Color Profile Yes ✕ No
Animated Portable Network Graphics
image/vnd.mozilla.apng
Extension
.apng.png
Container PNG Chunk Stream
Compression Deflate (Lossless)
Algorithm
Deflate (zlib)
Color Depth 8-bit (Indexed), 24-bit (TrueColor), 32-bit (RGBA)
Developed by Mozilla Corporation (Stuart Parmenter & Vladimir Vukićević)
Released 2004
Magic Bytes
89 50 4E 47 0D 0A 1A 0A
Full APNG reference →
JPEG XS Codestream
image/jxsc
Extension
.jxsc.jxs
Container None (Raw Codestream)
Compression Lossy (Visually Lossless) / Mathematically Lossless
Algorithm
JPEG XS (ISO/IEC 21122-1)
Color Depth 8-bit, 10-bit, 12-bit, 14-bit, 16-bit
Developed by Joint Photographic Experts Group (JPEG) / intoPIX
Released 2019
Magic Bytes
FF 10
Full JPEG-XS-Codestream reference →

Browser Support Comparison

Browser APNG JPEG-XS-Codestream
Chrome Chrome
✓ 59
 ✕
Firefox Firefox
✓ 3
 ✕
Safari Safari
✓ 8
 ✕
Edge Edge
✓ 79
 ✕
IE IE (Legacy)
✕ ✕
APNG

APNG Strengths

  • Supports 8-bit alpha transparency, completely solving the ugly 'white halo' problem inherent to GIFs
  • Gracefully degrades; viewers that do not support APNG will render a perfectly valid, static PNG of the first frame
  • Provides lossless compression that retains absolute pixel-perfect quality for UI elements and line art
Limitations
  • Because it relies on lossless Deflate compression, file sizes for complex, video-like animations can be massive compared to lossy formats like WebP or AVIF
  • Was initially rejected by the official PNG group, delaying its adoption for nearly a decade
  • Lacks native hardware decoding acceleration, unlike video-based animated formats (like MP4 or WebM)
JPEG-XS-Codestream

JPEG-XS-Codestream Strengths

  • Eliminates container overhead, maximizing parsing speed and minimizing latency to fractions of a millisecond
  • Highly optimized for direct hardware implementation in FPGAs and ASICs
  • Perfect for continuous data streaming over IP networks without needing to establish file headers
Limitations
  • Lacks standard container metadata (EXIF, XMP, ICC profiles), meaning color space and orientation data must be handled externally or out-of-band
  • Zero support in web browsers or standard consumer operating systems
  • Often requires specialized broadcast hardware or custom software libraries to decode

When to choose which format

APNG
Use APNG when…
  • High-Quality Web Animations
  • Stickers (Apple iMessage, LINE, Discord)
  • UI Loaders with Alpha Transparency
  • GIF Replacement
JPEG-XS-Codestream
Use JPEG-XS-Codestream when…
  • Hardware Decoding Pipelines (FPGA/ASIC)
  • Live Broadcast Infrastructure
  • Video over IP Transport
  • Embedded Camera Systems

More comparisons

APNG vs ACES → JPEG-XS-Codestream vs ACES → APNG vs AVCI → JPEG-XS-Codestream vs AVCI → APNG vs AVCS → JPEG-XS-Codestream vs AVCS → APNG vs AVIF → JPEG-XS-Codestream vs AVIF → All comparisons →
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