RA_RGBE(1)						      General Commands Manual							RA_RGBE(1)

NAME

       ra_rgbe - convert between different RADIANCE picture types

SYNOPSIS

       ra_rgbe [ -r ][ -e +/-stops ][ -f ][ -n frameno ] [ input [ outspec ] ]

DESCRIPTION

       Ra_rgbe	converts  between  RADIANCE run-length encoded and flat formats, and separates concatanated animation frames produced by rpict(1).
       The -e option specifies an exposure compensation in f-stops (powers of two).  Only integer stops are allowed, for efficiency.  By  default,
       ra_rgbe	produces  a  flat  RADIANCE  picture file from any type of RADIANCE input picture.  The -r option causes ra_rgbe to produce a run-
       length encoded file instead.

       If the input file consists of multiple animation frames as produced by rpict with the -S option, ra_rgbe will read each frame and write	it
       to  the	output file created by calling printf(3) with the output specification and frame number as arguments.  If the output specification
       begins with an exclamation mark ('!'), then this interpreted as a command spec., which is also run through printf with the frame number	to
       get the final command.  This command must accept a Radiance picture on its standard input, and may write results either to a file or to the
       standard output.  The -n option may be used to select a specific frame for output, and other frames in the input  will  be  skipped.   Nor-
       mally, all frames will be read and written.

       Ra_rgbe will report an error and exit if the target output file already exists, unless the -f option is given.  If the output file is miss-
       ing, the standard output is used.  If the input file is missing or set to '-', the standard input is used.

NOTES

       The file format for RADIANCE pictures was changed between release 1.4 and release 2.0.  The older format can still be read by all the  pro-
       grams, but only the newer format is produced.  This newer format cannot be read by RADIANCE software prior to release 2.0.

       Ra_rgbe	provides some downward compatibility by producing files that can be read by older RADIANCE software.  The resultant files are also
       easier to manipulate with programs designed to read raw raster data.

       The other use for ra_rgbe is as a quicker way to adjust the exposure of a RADIANCE picture than pfilt(1), since ra_rgbe only allows integer
       f-stop changes.	In this mode, ra_rgbe should be used with the -r option.

AUTHOR

       Greg Ward

ACKNOWLEDGEMENT

       Work on this program was initiated and sponsored by the LESO group at EPFL in Switzerland.

SEE ALSO

       pfilt(1), printf(1), ra_xyze(1), rpict(1)

RADIANCE
							      1/23/98								RA_RGBE(1)