Grok

<span> <a href="https://jpeg.org/jpeg2000/index.html" target="_blank"> <img src="https://jpeg.org/images/jpeg2000-logo.svg" width=200, height=200 /> </a> </span> <p>

Grok is an open-source JPEG 2000 codec licensed under AGPL v3. It is integrated into GDAL via the JP2Grok driver.

Performance

Benchmark results (16 threads, GDAL release build, Fedora 42):

| Workflow | Grok (JP2Grok) | Kakadu (JP2KAK) | OpenJPEG | |------------------------------|----------------|------------------|--------------| | Spot 6 (Network Storage) | 35.17 s | 344 s | 85 s | | Spot 6 (Local Storage) | 26.92 s | 30.57 s | 52.09 s | | Pleiades (Region) | 0.74 s | 1.41 s | 4.28 s |

Features

• High Throughput JPEG 2000 (HTJ2K) support
• Random-access sub-image decoding (TLM + PLT markers)
• ICC color profiles, XML/IPTC/XMP/EXIF metadata
• Monochrome, sRGB, palette, YCC, extended YCC, CIELab, CMYK
• 1–16 bit precision
• JPEG/PNG/BMP/TIFF/RAW/PNM/PAM I/O
• Linux (x86-64/AArch64), Windows, macOS, WebAssembly

Testing

• 2,000+ unit tests
• Continuous fuzzing via OSS-Fuzz

Language Bindings

• Python, C#, Java (SWIG)
• Rust (bindgen)

Links

• Installation
• Language Bindings
• Wiki & Docs
• GitHub

Quick Build

git clone --recursive https://github.com/GrokImageCompression/grok.git
cd grok
cmake -B build
cmake --build build --parallel

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