\ .\" This man page was generated by the Netpbm tool 'makeman' from HTML source. .\" Do not hand-hack it! If you have bug fixes or improvements, please find .\" the corresponding HTML page on the Netpbm website, generate a patch .\" against that, and send it to the Netpbm maintainer. .TH "Ppmtoyuvsplit User Manual" 0 "06 March 2003" "netpbm documentation" .UN lbAB .SH NAME ppmtoyuvsplit - convert a PPM image to 3 subsampled raw YUV files .UN lbAC .SH SYNOPSIS \fBppmtoyuvsplit\fP \fIbasename\fP [\fIppmfile\fP] .UN lbAD .SH DESCRIPTION .PP This program is part of .BR "Netpbm" (1)\c \&. .PP \fBppmtoyuvsplit\fP reads a PPM image as input. Produces 3 raw files \fIbasename\fP.Y, \fIbasename\fP.U and \fIbasename.V\fP as output. .PP 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. .PP The YUV values are scaled according to CCIR.601, as assumed by MPEG. .UN lbAE .SH SEE ALSO .BR "yuvsplittoppm" (1)\c \&, .BR "ppmtoyuv" (1)\c \&, .BR "ppmtoeyuv" (1)\c \&, .BR "ppmtompeg" (1)\c \&, .BR "ppm" (5)\c \& .UN lbAF .SH AUTHOR .PP Copyright (C) 1993 by Andre Beck. (\fIAndre_Beck@IRS.Inf.TU-Dresden.de\fP) .PP Based on ppmtoyuv.c .SH DOCUMENT SOURCE This manual page was generated by the Netpbm tool 'makeman' from HTML source. The master documentation is at .IP .B http://netpbm.sourceforge.net/doc/ppmtoyuvsplit.html .PP