Convert ARW to PPM / PNM

The ARW (Sony Alpha Raw) format is a proprietary raw image container generated by Sony Alpha, Cyber-shot, and NEX series digital cameras. It adheres to the TIFF (Tag Image File Format) specification, storing unprocessed photodiode data from the image sensor in either uncompressed, lossless compressed, or lossy compressed (11-bit + 7-bit delta) variations. The file encapsulates extensive EXIF metadata, maker notes, and a JPEG preview, requiring specific demosaicing algorithms to interpret the Bayer pattern data for display.

Opening ARW files requires software capable of decoding Sony's proprietary Bayer interpretation. Sony provides the free Imaging Edge Desktop software for native handling. Industry-standard post-production tools such as Adobe Lightroom, Capture One, and DxO PhotoLab offer full support. On Windows, the Microsoft Raw Image Extension allows native viewing in the Photos app, while macOS Preview supports most ARW iterations natively via Apple's Core Image RAW engine.

The Portable Pixel Map (PPM) format is a lowest-common-denominator color image format developed by Jef Poskanzer as part of the Netpbm project. It stores pixels as uncompressed RGB triplets (Red, Green, Blue) in either a plain ASCII text format (P3 header) or a more efficient binary format (P6 header). The file structure is extremely minimal, consisting of a magic number identifier, dimensions (width and height), maximum color value, and the pixel data itself, making it easily parsable by simple scripts but inefficient for storage compared to compressed formats like JPEG or PNG.

Native support for PPM files is absent in standard Windows or macOS photo viewers. Users typically require specialized image manipulation software to view or convert these files. GIMP (GNU Image Manipulation Program) and IrfanView are the primary tools for opening PPM files on desktop environments. On Linux systems, the Netpbm toolkit and ImageMagick suite provide command-line utilities for processing and converting PPM data.