Image MIME Reference
JPEG-2000
JPEG 2000 Core Image File
image/jp2
VS
Truevision TGA (Legacy MIME Alias)
image/x-tga
TGA
A complete technical comparison of JPEG 2000 Core Image File and Truevision TGA (Legacy MIME Alias) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
JPEG-2000 wins on browser support
Feature Support
| Feature | JPEG-2000 | TGA |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | Yes | ✕ No |
| HDR Support | Yes | ✕ No |
| EXIF Metadata | Yes | ✕ No |
| ICC Color Profile | Yes | ✕ No |
JPEG 2000 Core Image File
image/jp2
Extension
.jp2.j2k.jpf.jpx.jpm
Container
JP2 (ISO/IEC 15444-1)
Compression
Lossy / Lossless
Algorithm
Discrete Wavelet Transform (DWT)
Color Depth
8-bit, 16-bit, 32-bit, 38-bit
Developed by
Joint Photographic Experts Group
Released
2000
Magic Bytes
00 00 00 0C 6A 50 20 20 0D 0A 87 0A
Truevision TGA (Legacy MIME Alias)
image/x-tga
Extension
.tga.icb.vda.vst
Container
Truevision TGA Footer/Header
Compression
Uncompressed / Run-Length Encoding (RLE)
Algorithm
NoneRLE
Color Depth
8-bit (Grayscale or Indexed), 16-bit (High Color), 24-bit (True Color), 32-bit (True Color with Alpha Channel)
Developed by
Truevision Inc.
Released
1984
Magic Bytes
54 52 55 45 56 49 53 49 4F 4E 2D 58 46 49 4C 45 2E 00 (At the end of the file)
Browser Support Comparison
| Browser | JPEG-2000 | TGA |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✓ 5+
|
✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
JPEG-2000
JPEG-2000 Strengths
- Superior compression efficiency over baseline JPEG without introducing blocking artifacts
- True mathematically lossless compression available in the same format
- Extremely scalable: a single file can be decoded at various resolutions (thumbnails to full size) without loading the entire file
Limitations
- Very poor native web browser support prevents it from being a web standard
- High computational complexity makes encoding and decoding significantly slower than JPEG
- Early patent concerns and complex licensing hindered its initial adoption rate
TGA
TGA Strengths
- Incredibly simple byte layout allows developers to write custom loaders and exporters in a few dozen lines of code, bypassing the need for heavy external libraries
- Native support for 8-bit alpha channels ensures flawless transparency masking for real-time 3D rendering
- Fast, predictable RLE decoding requires almost no CPU overhead compared to DEFLATE (PNG) or DCT (JPEG)
Limitations
- RLE compression is relatively weak by modern standards, resulting in large file sizes
- Lacks a standard magic byte header at the beginning of the file, making file-sniffing unreliable for older v1.0 files
- Zero support in web browsers; must be converted to PNG or WebP for web delivery
When to choose which format
JPEG-2000
Use JPEG-2000 when…
- Digital Cinema (DCP)
- Medical Imaging (DICOM)
- Geospatial Data
- Archival Preservation
TGA
Use TGA when…
- Video Game 3D Textures and Materials
- 3D Rendering and Animation Sequences
- Legacy Video Production Workflows