Convert PNM to JXL

The PNM (Portable Anymap) file extension, developed by Jef Poskanzer in the 1980s, stands for Portable Any Map. It is an uncompressed raster graphics format designed for portable image storage and exchange, encompassing three sub-formats: PBM (Portable Bitmap), PGM (Portable Graymap), and PPM (Portable Pixmap). PNM files store image data in plain text or binary format, ensuring easy usage across different platforms and applications. This format is widely supported by various image editing software and is valued for its simplicity and lossless compression.

The JPEG XL (JXL) file extension, is a next-generation image format developed by the Joint Photographic Experts Group, combining Google's PIK and Cloudinary's FUIF formats. It supports both lossy and lossless compression, offering up to 60% better compression efficiency compared to traditional JPEG, while maintaining high image quality. Standardized in 2021, JPEG XL is designed for web delivery, professional photography, and digital printing, supporting ultra-high-resolution images, wide color gamuts, and advanced features like progressive decoding and multiple layers.