NAME¶

ppmtoyuvsplit - convert a PPM image to 3 subsampled raw YUV files

SYNOPSIS¶

ppmtoyuvsplit basename [ppmfile]

DESCRIPTION¶

This program is part of Netpbm(1).

ppmtoyuvsplit reads a PPM image as input. Produces 3 raw files basename.Y, basename.U and basename.V as output.

The output files are the subsampled raw YUV representation of the input PPM image, as required by the Stanford MPEG codec. The Y output file contains a byte for each pixel in the image, with the rows going from top to bottom and the columns within each row going left to right. The U and V output files are arranged similarly, except that each byte represents a square of 4 pixels of the image. The value is the arithmetic mean of the value for each of those 4 pixels. Hence, the Y file is 4 times the size of the U file or V file.

The YUV values are scaled according to CCIR.601, as assumed by MPEG.

SEE ALSO¶

yuvsplittoppm(1), ppmtoyuv(1), ppmtoeyuv(1), ppmtompeg(1), ppm(1)

AUTHOR¶

Copyright (C) 1993 by Andre Beck. (Andre_Beck@IRS.Inf.TU-Dresden.de)

Based on ppmtoyuv.c