Convert PHM to J2C

The PHM file extension stands for Portable Float-map Image (16-bit half), a format used for storing High Dynamic Range (HDR) images with 16-bit half-precision floating-point values. This format is particularly useful in applications requiring precise color representation and extensive dynamic range, such as computer graphics, image processing, and scientific visualization. Originating from the Portable FloatMap (PFM) format, PHM was developed to provide a more efficient storage solution by utilizing half-precision floats, thereby reducing file size while maintaining significant detail and accuracy.

The J2C file extension stands for JPEG 2000 Code Stream, a format defined in Part 1 of the JPEG 2000 standard. Developed by the Joint Photographic Experts Group (JPEG) from 1997 to 2000, J2C files utilize wavelet-based compression, supporting both lossy and lossless compression. This format is primarily used for high-quality image storage and transmission, offering superior compression efficiency and flexibility compared to the original JPEG standard. J2C files are often embedded within other file formats like JP2 for enhanced metadata support.