- Convert a PNM image to a DDIF image file:
pnmtoddif path/to/image.pnm > path/to/image.ddif
- Explicitly specify the horizontal and vertical resolution of the output image:
pnmtoddif -resolution horizontal_dpi vertical_dpi path/to/image.pnm > path/to/image.ddif
pnmtoddif [-resolution x y] [pnmfile [ddiffile]]
This program is part of Netpbm(1).
pnmtoddif takes a PNM image and converts it into a DDIF image file.
pnmtoddif writes PBM format (bitmap) data as a 1 bit DDIF, PGM format data (grayscale) as an 8 bit grayscale DDIF, and PPM format (color) data as an 8,8,8 bit color DDIF. pnmtoddif writes any DDIF image file uncompressed. The data plane organization is interleaved by pixel.
In addition to the number of pixels in the width and height dimension, DDIF images also carry information about the size that the image should have, that is, the physical space that a pixel occupies. Netpbm images do not carry this information, hence you have to supply it externally. The default of 78 dpi has the beneficial property of not causing a resize on most Digital Equipment Corporation color monitors.
In addition to the options common to all programs based on libnetpbm (most notably -quiet, see Common Options ), pnmtoddif recognizes the following command line option:
- resolution x y
The horizontal and vertical resolution of the output image in dots per inch. Default is 78 dpi.
The filename for the image file in pnm format. Default is to read from Standard Input.
The filename for the image file to be created in DDIF format. By default, pnmtoddif writes to Standard Output.
Burkhard Neidecker-Lutz, Digital Equipment Corporation, CEC Karlsruhe firstname.lastname@example.org
This manual page was generated by the Netpbm tool 'makeman' from HTML source. The master documentation is at