# sldtoppm

Updated: 10 October 1991
Table Of Contents

## NAME

sldtoppm - convert an AutoCAD slide file to a PPM image

## SYNOPSIS

sldtoppm [-adjust] [-dir] [{-height|-ysize} s] [-info] [{-lib|-Lib} name] [-scale s] [-verbose] [{-width|-xsize} s] [slidefile]

All options can be abbreviated to their shortest unique prefix.

## DESCRIPTION

This program is part of Netpbm.

sldtoppm reads an AutoCAD® slide file and outputs a PPM image. If you don't specify slidefile, sldtoppm reads input from Standard Input. sldtoppm uses the ppmdraw library to convert the vector and polygon information in the slide file to a raster; see the file ppmdraw.h for details on this package.

## OPTIONS

-adjust
  If the display on which the slide file was created had non-square pixels, when you process the slide with sldtoppm and don't specify -adjust, sldtoppm issues the following warning;

  > Warning - pixels on source screen were non-square.

  Specifying -adjust will correct the image width to compensate. Specifying the -adjust option causes sldtoppm to scale the width of the image so that pixels in the resulting PPM image are square (and hence circles appear as true circles, not ellipses). The scaling is performed in the vector domain, before scan converting the objects. The results are, therefore, superior in appearance to what you'd obtain were you to perform the equivalent scaling with pamscale after the bitmap had been created.

-dir
  The input is assumed to be an AutoCAD slide library file. A directory listing each slide in the library is printed on standard error.
-height size
  Scales the image in the vector domain so it is size pixels in height. If you don't specify -width or -xsize, sldtoppm adjusts the width to preserve the pixel aspect ratio.
-info
  Dump the slide file header on standard error, displaying the original screen size and aspect ratio among other information.
-lib name
  Extracts the slide with the given name from the slide library given as input. sldtoppm converts the specified name to upper case.
-Lib name
  Extracts the slide with the given name from the slide library given as input. sldtoppm uses name in the case specified; it does not convert it to upper case.
-scale s
  Scales the image by factor s, which may be any floating point value greater than zero. sldtoppm does the scaling after aspect ratio adjustment, if any. Since it does the scaling in the vector domain, before rasterisation, the results look much better than running the output of sldtoppm through pamscale.
-verbose
  Dumps the slide file header and lists every vector and polygon to Standard Error.
-width size
  Scales the image in the vector domain so it is size pixels wide. If you don't specify -height or -ysize, sldtoppm adjusts the height to preserve the pixel aspect ratio.
-xsize size
  Scales the image in the vector domain so it is size pixels wide. If you don't specify -height or -ysize, sldtoppm adjusts the height to preserve the pixel aspect ratio.
-ysize size
  Scales the image in the vector domain so it is size pixels in height. If you don't specify -width or -xsize, sldtoppm adjusts the width to preserve the pixel aspect ratio.

## LIMITATIONS

sldtoppm can convert only Level 2 slides. Level 1 format has been obsolete since the advent of AutoCAD Release 9 in 1987, and was not portable across machine architectures.

Slide library items with names containing 8 bit (such as ISO) or 16 bit (Kanji, for example) characters may not be found when chosen with the -lib option unless sldtoppm was built with character set conversion functions appropriate to the locale. You can always retrieve slides from libraries regardless of the character set by using the -Lib option and specifying the precise name of library member. Use the -dir option to list the slides in a library if you're unsure of the exact name.

## SEE ALSO

AutoCAD Reference Manual: Slide File Format, pamscale, ppm

## AUTHOR

    John Walker
    Autodesk SA
    Avenue des Champs-Montants 14b
    CH-2074 MARIN
    Suisse/Schweiz/Svizzera/Svizra/Switzerland
        Usenet:kelvin@Autodesk.com
        Fax:038/33 88 15
        Voice:038/33 76 33

Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, without any conditions or restrictions. This software is provided "as is" without express or implied warranty.

AutoCAD and Autodesk are registered trademarks of Autodesk, Inc.

## Table Of Contents

- NAME
- SYNOPSIS
- DESCRIPTION
- OPTIONS
- BUGS
- SEE ALSO
- AUTHOR