NAME

       ra_bmp - convert RADIANCE picture to/from Windows BMP image

SYNOPSIS

       ra_bmp  [ -b ][ -g gamma ][ -e spec ][ -p xr yr xg yg xb yb xw yw ] [ [ input|- [ output ]
       ]
       ra_bmp -r [ -g gamma ][ -e +/-stops ] [ [ input|- [ output ] ]

DESCRIPTION

       Ra_bmp converts between RADIANCE and a Windows BMP image.  During forward conversion,  the
       -b option produces 8-bit grayscale output rather than 24-bit RGB.  The -g option specifies
       the exponent used in monitor gamma correction; the default value is 2.2.   The  -e  option
       specifies  a  tone-mapping method or exposure compensation.  If the argument is one of the
       special words "auto", "human", or "linear", the image will be tone-mapped  with  histogram
       adjustment, human vision simulation, or an averaged linear exposure, respectively.  (These
       words may be abbreviated by one or more letters.)  Otherwise, the  exposure  specification
       is  interpreted as a linear compensation value in integer f-stops, which must be proceeded
       by a '+' or '-'.  The CRT color output primaries may be specified with the -p option.

       The -r option invokes a reverse conversion,  from  a  Windows  BMP  image  to  a  RADIANCE
       picture.  Tone-mapping and monitor primaries are not supported for reverse conversion.

       Ra_bmp  can  accept 16-bit or color-mapped BMP files on input, but cannot not produce them
       on output.

       A hyphen ('-') may be specified to indicate standard input for either forward  or  reverse
       conversion  so  that  an output file may be specified.  If the BMP input is taken from the
       standard input or sent to the standard output without tone-mapping, then the scanlines may
       be  reversed  from their usual ordering.  Reversed scanlines sometimes causes difficulties
       for programs attempting to interpret the resulting RADIANCE picture or  BMP  image,  which
       may be rejected or displayed inverted.

AUTHOR

       Greg Ward

SEE ALSO

       pfilt(1), ra_ppm(1), ra_pr(1), ra_pr24(1), ra_t8(1), ra_t16(1), ra_tiff(1), ximage(1)