NAME

       pamtosvg - convert a Netpbm image to a SVG (Scalable Vector Graphics) image

SYNOPSIS

       pamtosvg

       [-background-color=colorname]   [-centerline]  [-corner-threshold=angle]  [-corner-always-
       threshold=angle]    [-corner-surround=integer]    [-tangent-surround=integer]     [-error-
       threshold=float]   [-filter-iterations=count]   [-line-reversion-threshold=float]  [-line-
       threshold=float] [-width-weight-factor=float] [-preserve-width] [-remove-adjacent-corners]
       [-log] [-report-progress] [pnmfile]

       Minimum  unique  abbreviation of option is acceptable.  You may use double hyphens instead
       of single hyphen to denote options.  You may use white space in place of the  equals  sign
       to separate an option name from its value.

DESCRIPTION

       This program is part of Netpbm(1).

       pamtosvg reads a PNM image as input and produce an SVG (Scalable Vector Graphics) image as
       output.  Thus, it traces curves in the input image and  creates  a  set  of  splines  that
       represent the image.

       SVG  is  a vector image format, which means it describes curves that compose an image.  By
       contrast, PNM is a raster format, which means it describes dots  that  compose  an  image.
       The  main  practical  difference between the two types is that you can scale vector images
       better.  A vector image also takes a lot less data to describe an image if  the  image  is
       composed of simple curves.

       That  means  it  is  really  an  understatement  to  say  that pamtosvg is an image format
       converter.  It's really an image tracer.  Its main job is to trace a raster image and find
       the lines in it.  It then represents its findings in SVG format.

       pamtosvg does the same kind of thing that StreamLine, CorelTrace, and Autotrace do.  It is
       in fact derived from Autotrace.

       SVG is a gigantic format, capable of amazing things.  pamtosvg exploits only a  morsel  of
       it.   The  SVG  image produced by pamtosvg consists of a single <svg> element, which has a
       "width" attribute and a "height" attribute.  The value of  that  element  is  composed  of
       <path> elements.  That's it.

       In the SVG output, distances are unitless, with one unit corresponding to one pixel of the
       input.

       So that pamtosvg will find simple curves in the image, you may  want  to  remove  speckles
       from  it  with  pbmclean  and consolidate multiple shades into single colors with pnmquant
       first.

       For  more  information  on  SVG,  see  the  Worldwide  Web  Consortium's  SVG   web   page
       ⟨http://www.w3.org/Graphics/SVG/⟩ .

OPTIONS

       In addition to the options common to all programs based on libnetpbm (most notably -quiet,
       see
        Common Options ⟨index.html#commonoptions⟩ ), pamtosvg recognizes  the  following  command
       line options:

       -background-color=colorname
              Treat the specified color as the background color and ignore it.

              If you don't specify this option, pamtosvg does not recognize any background color.

              Specify the color (colorname) as described for the argument of the pnm_parsecolor()
              library routine ⟨libnetpbm_image.html#colorname⟩ .

       -centerline
              Trace an object's centerline.

              By default, pamtosvg traces an object's outline.

       -corner-always-threshold=angle
              Consider any angle at a pixel which falls below angle angle  (in  decimal  floating
              point degrees) as a corner, even if it is bordered by other corner pixels.  Default
              is 60 degrees.

       -corner-surround=integer
              Consider the specified number of pixels on either side of a point when  determining
              if that point is a corner.  Default is 4.

       -corner-threshold=angle
              Consider  any  pixel which forms an angle with its predecessors and successors that
              is smaller than angle (in decimal floating point degrees) as a corner.  Default  is
              100.

       -error-threshold=float
              Subdivide  fitted  curves  that  are  offset  by  a  number of pixels exceeding the
              specified number.  Default is 2.0.

       -filter-iterations=integer
              Smooth the curve the specified number of times prior to fitting Default is 4.

       -line-reversion-threshold=float
              When a spline is closer to a straight line than the specified real number  weighted
              by  the square of the curve length, maintain it as a straight line, even if it is a
              list with curves.

              Default is .01.

       -line-threshold=float
              If a spline does not deviate from the straight line defined  by  its  endpoints  by
              more than the specified number of pixels, then treat it as a straight line.

              Default is 1.

       -log   Create  a log of the curve tracing process (suitable for debugging).  Put it in the
              file named inputfile.log in the current directory, where inputfile is the  root  of
              the  input  file  name, or "pamtosvg" if the input is from Standard Input or a file
              with a weird name.

       -preserve-width
              Preserve line width prior to thinning.  Meaningful only with -centerline.

       remove-adjacent-corners
              Remove adjacent corners.

       -report-progress
              Report the progress of the tracing to Standard Error as it happens.

       -tangent-surround
              Consider the specified number of points to either side of a  point  when  computing
              the tangent at that point.  Default is 3.

       -width-weight-factor
              Weight factor for fitting the linewidth.

APPLICATION NOTES

       A  convenient  way  to view an SVG document is with a web browser.  Many understand a file
       whose name ends in ".svg" to be an SVG image and can render it.

SEE ALSO

       pnmquant(1), pbmclean(1), pnm(1), Autotrace ⟨http://autotrace.sourceforge.net⟩

HISTORY

       pamtosvg was added to Netpbm in Version 10.33 (March 2006).

       The core of pamtosvg -- the curve tracing logic -- was taken nearly unmodified from Martin
       Weber's  Autotrace program.  That program duplicates a lot of Netpbm function, so pamtosvg
       is a much leaner program.

       Bryan Henderson created pamtosvg, basically just by adapting Autotrace to Netpbm.

       Autotrace was first released in 2000 and updates were released through 2002.  A number  of
       people  wrote  the  code  in  it,  but  Masatake  Yamato and Martin Weber appear to be the
       principal creators of it.

       As of June 2006, there was a Sourceforge project ⟨http://autotrace.sourceforge.net⟩    for
       it.

DOCUMENT SOURCE

       This  manual page was generated by the Netpbm tool 'makeman' from HTML source.  The master
       documentation is at

              http://netpbm.sourceforge.net/doc/pamtosvg.html