PGM File Documentation

Overview

Feature Value
File Extension .pgm
File Type Portable Gray Map Image
Format Type Bitmap
Color Depth Grayscale
MIME Type image/x-portable-graymap
Header ASCII (P2) or Binary (P5)
Max Color Value (Maxval) Typically 255
Image Data Representation Binary or ASCII Text
Compression None (usually)
Palette No palette (grayscale)
Development By Jef Poskanzer
Release Date 1988
Supported by Various image viewers and editors
Character Encoding ASCII for metadata and dimensions
Main Usage Simple, portable images and scientific work
Advantages Simple format; easy to parse and generate
Disadvantages No compression; large file size for big images
Pixel Format 8 or 16 bits per pixel
Resolution No inherent resolution, dependent on display
Transparency No support for transparency