RA_PR(1)                                                              RA_PR(1)



NNAAMMEE
       ra_pr - convert RADIANCE picture to/from pixrect rasterfile

SSYYNNOOPPSSIISS
       rraa__pprr  [  --dd  ][  --bb ][ --cc nnccoolloorrss ][ --gg ggaammmmaa ][ --ee ++//--ssttooppss ] iinnppuutt [
       oouuttppuutt ]
       rraa__pprr --rr [ --gg ggaammmmaa ][ --ee ++//--ssttooppss ] [ iinnppuutt [ oouuttppuutt ] ]

DDEESSCCRRIIPPTTIIOONN
       _R_a___p_r converts between RADIANCE and pixrect rasterfile formats.  In the
       default  mode,  a RADIANCE picture is converted to a pixrect rasterfile
       of the same horizontal and vertical dimensions with 8-bits  per  pixel.
       The _-_d option turns off dithering.  The _-_b option converts the image to
       black and white, for improved quality on greyscale monitors.  Only with
       this  option  can  the input be taken from stdin.  The _-_c option allows
       fewer than 256 colors.  The _-_g option specifies the  exponent  used  in
       gamma  correction;  the default value is 2.2.  An exponent of 1.0 turns
       gamma correction off.  The _-_e option specifies an exposure compensation
       in  f-stops (powers of two).  Only integer stops are allowed, for effi-
       ciency.  The _-_r option invokes a reverse  conversion,  from  a  pixrect
       rasterfile  to  a RADIANCE picture.  If the output file is missing, the
       standard output is used.

AAUUTTHHOORRSS
       Greg Ward
       Paul Heckbert provided the code for color quantization

BBUUGGSS
       Only standard 8-bit color rasterfiles are read or written.

SSEEEE AALLSSOO
       pfilt(1),  ra_bmp(1),  ra_bn(1),   ra_ppm(1),   ra_pr24(1),   ra_t8(1),
       ra_t16(1), ra_tiff(1), ximage(1)



RADIANCE                           11/15/93                           RA_PR(1)
