Convert hevc to pgm

What is the difference between .hevc and .pgm?

Description: The High Efficiency Video Coding (HEVC) file, commonly known by its file extension .hevc, represents a video compression format designed to substantially improve coding efficiency compared to its predecessor, H.264/AVC. Aimed at enabling higher resolution video content such as 4K and 8K, HEVC is adept at maintaining high-quality video at roughly half the bitrate, significantly reducing file sizes without compromising on visual fidelity. This efficiency makes HEVC particularly valuable in streaming media applications.; A PGM file is a grayscale image file saved in the portable gray map (PGM) format and encoded with one or two bytes (8 or 16 bits) per pixel. It contains header information and a grid of numbers that represent different shades of gray from black (0) to white (up to 65,536). PGM files are typically stored in ASCII text format, but also have a binary representation.