NAME

rletoabA62 - Convert from RLE Format to Abekas A62 Dump Format

SYNOPSIS

rletoabA62 [ -N ] [ -f n ] [ -n n ] [ infile ]

DESCRIPTION

RletoabA62 converts a raster file in the Utah Raster Toolkit RLE format into a format suitable for writing to an Abekas A62 dump tape and subsequent loading onto the Abekas disk. The generated image is 768 pixels wide and 512 pixels high. If the input is larger, it is truncated. If it is smaller, it is padded on the top and right with black. The output is written to stdout, and should be written to a tape in 24K byte blocks with dd as in the following:

dd of=/dev/rmt8 obs=24k

Normally, the output is processed with a simple digital filter; this feature may be turned off with an option. RletoabA62 normally writes two consecutive frames, normally starting at frame 1.

Input is taken from stdin unless a file name is given on the command line. Only a single file may be given, and so if multiple invocations of rletoabA62 are performed in a script, care must be taken to tell the program to convert the data for the proper Abekas frame number (1-4). Otherwise, the colors will appear wrong; they will be rotated on a vector scope diagram.

EXAMPLE

The following example converts all files ending in .rle in the current directory and writes them to a tape. Two frames are written per image and the frame number is incremented accordingly.

frame=1
number=2
for file in *.rle
do
rletoabA62 -f $frame $file
frame=`expr $ \( $frame - 1 $ + $number \) % 4 + 1`
done |
dd of=/dev/rmt8 obs=24k

OPTIONS

Options are parsed by getopt(3).

-N: Do not apply digital filtering.
-f n: Create the first frame as Abekas frame number n, having a value from one to four. Consecutive frames increment this number modulo four. The default is one.
-n n: Write n frames of output, incrementing the frame number each time. The default is two.

AUTHOR

Bob Brown, RIACS.

BUGS

This program does not preserve the aspect ratio of the input.