- Extension
- .g4
- .pnm
- Format
- Binary
- Binary
- Category
- Fax
- Raster Image
- Developer
- Computer Fax Systems (CFS)
- Jef Poskanzer
- Description
- Group 4 (G4) used for black and white lossless compression to maintain high-quality images, commonly used in TIFF format compression by fax machines. A picture is seen as black dots and lines on a blank page; the fewer the dots and lines are, the lesser the file size.
- The PNM (Portable Any Map Image) file format is a subset of the broader Netpbm format, designed for storing various types of digital images. It acts as an umbrella term for three specific types of grayscale, color, and black-and-white images, represented by PBM (Portable Bitmap), PGM (Portable Graymap), and PPM (Portable Pixmap) formats respectively. PNM files are known for their simplicity and ease of conversion to other image formats.
- MIME Type
- image/g4fax
- application/x-portable-anymap
