PGMB Files
Binary Portable Gray Map Graphics Files

PGMB is a data directory of Binary PGM files, the binary form of the portable gray map PGM format. It is a simple gray map description. The definition is as follows:

• the typical file extension is ".pgm", but an extension of ".pnm" is also occasionally used.
• A "magic number" for identifying the file type. A binary PGM file's magic number is the two characters "P5".
• Whitespace (blanks, TABs, CRs, LFs).
• A width, formatted as ASCII characters in decimal.
• Whitespace.
• A height, again in ASCII decimal.
• Whitespace.
• The maximum gray value, MAXVAL, again in ASCII decimal. MAXVAL must be between 0 and 255.
• A single character of whitespace, typically a newline;
• Width * height gray values, each stored as a plain byte, between 0 and the specified maximum value, separated by whitespace, starting at the top-left corner of the graymap, proceeding in normal English reading order. A value of 0 means black, and the maximum value means white.

Binary PGM File Characteristics:

• binary
• Gray scale only
• 2D
• No compression
• 1 image

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Related Data and Programs:

PBMB, a data directory which contains examples of binary PBM files, binary Portable Bit Map 2D graphics, black and white;

PGMA, a data directory which contains examples of ASCII PGM files, ASCII Portable Gray Map, 2D graphics;

PPMB, a data directory which contains examples of binary PPM files, Portable Pixel Map (binary) 2D graphics, color;

Reference:

1. the NETPBM homepage.

Sample Files:

• baboon.pgm, a baboon.
• baboon.png, a PNG version.
• barbara.pgm.
• barbara.png, a PNG version.
• bird.pgm, a bird.
• bird.png, a PNG version.
• buffalo.pgm, a small herd of buffalo.
• buffalo.png, a PNG version.
• casablanca.pgm, a still from the movie "Casablanca".
• casablanca.png, a PNG version.
• coins.pgm, some coins.
• coins.png, a PNG version.
• columns.pgm, a 640x480 image of a person standing by some columns;
• columns.png, a PNG image.
• dewey_defeats_truman.pgm, a famously erroneous newspaper headline.
• dewey_defeats_truman.png, a PNG version.
• feep.pgm, a simple 7 by 24 example that displays "FEEP" in block letters.
• feep.png, a PNG image.
• ladyzhenskaya.pgm.
• ladyzhenskaya.png, a PNG version.
• lena.pgm.
• lena.png, a PNG version.
• lena_noisy.pgm, a "noisy" version of the lena image.
• lena_noisy.png, a PNG version.
• milking.pgm, a cow being milked.
• milking.png, a PNG version.
• mona_lisa.pgm, the Mona Lisa.
• mona_lisa.png, a PNG version.
• pbmlib.pgm, a file created by PBMLIB.
• pbmlib.png, a PNG version.
• pepper.pgm, a picture of peppers.
• pepper.png, a PNG version.
• roi_14.pgm, a 507 wide by 505 high image an MRI, the 14th in a sequence.11
• roi_14.png, a PNG image.
• snap.pgm, a snapshot of a mother and child.
• snap.png, a PNG version.
• surf.pgm, a beach picture.
• surf.png, a PNG image.

You can go up one level to the DATA page.