PGM to EXR Converter

EXR is a high-dynamic-range raster image format developed by Industrial Light & Magic (ILM) internally since 1999 and publicly released as open-source software in January 2003. OpenEXR was created to meet the demanding requirements of feature film visual effects compositing, where scenes routinely contain extreme brightness ranges — from deep shadows to specular highlights on water, metal, or light sources — that exceed the precision of 8-bit or 16-bit integer formats. EXR stores pixel data in 16-bit floating-point (half) or 32-bit floating-point per channel, providing over 30 stops of dynamic range with smooth precision across the entire luminance spectrum. The format supports an arbitrary number of channels (not just RGBA), tiled and scanline storage, multiple compression methods (lossless ZIP, lossy B44 and DWAA/DWAB for preview quality), multi-part files containing multiple views or layers, and deep pixel data where each pixel stores multiple depth-sorted samples for volumetric effects. One advantage is compositing fidelity: the floating-point precision means that color grading, exposure adjustments, lighting changes, and multi-layer compositing operations produce mathematically correct results without the banding, clipping, or quantization artifacts inherent in integer formats. EXR's adoption as the VFX industry standard is another core strength — it is the default interchange format for Foundry Nuke, Autodesk Flame, Blackmagic Fusion, Adobe After Effects, and every major 3D renderer, and its open-source C++ library is embedded in hundreds of production tools.