1Pamtosvg User Manual(0) Pamtosvg User Manual(0)
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6 pamtosvg - convert a Netpbm image to a SVG (Scalable Vector Graphics)
7 image
8
11 pamtosvg
12 [-background-color=colorname] [-centerline] [-corner-threshold=angle]
14 [-corner-always-threshold=angle] [-corner-surround=integer] [-tangent-
15 surround=integer] [-error-threshold=float] [-filter-iterations=count]
16 [-line-reversion-threshold=float] [-line-threshold=float] [-width-
17 weight-factor=float] [-preserve-width] [-remove-adjacent-corners]
18 [-log] [-report-progress] [pnmfile]
19 Minimum unique abbreviation of option is acceptable. You may use dou‐
21 ble hyphens instead of single hyphen to denote options. You may use
22 white space in place of the equals sign to separate an option name from
23 its value.
24
27 This program is part of Netpbm(1).
28 pamtosvg reads a PNM image as input and produce an SVG (Scalable Vector
30 Graphics) image as output. Thus, it traces curves in the input image
31 and creates a set of splines that represent the image.
32 SVG is a vector image format, which means it describes curves that com‐
34 pose an image. By contrast, PNM is a raster format, which means it
35 describes dots that compose an image. The main practical difference
36 between the two types is that you can scale vector images better. A
37 vector image also takes a lot less data to describe an image if the
38 image is composed of simple curves.
39 That means it is really an understatement to say that pamtosvg is an
41 image format converter. It's really an image tracer. Its main job is
42 to trace a raster image and find the lines in it. It then represents
43 its findings in SVG format.
44 pamtosvg does the same kind of thing that StreamLine, CorelTrace, and
46 Autotrace do. It is in fact derived from Autotrace.
47 SVG is a gigantic format, capable of amazing things. pamtosvg exploits
49 only a morsel of it. The SVG image produced by pamtosvg consists of a
50 single <svg> element, which has a "width" attribute and a "height"
51 attribute. The value of that element is composed of <path> elements.
52 That's it.
53 In the SVG output, distances are unitless, with one unit corresponding
55 to one pixel of the input.
56 So that pamtosvg will find simple curves in the image, you may want to
58 remove speckles from it with pbmclean and consolidate multiple shades
59 into single colors with pnmquant first.
60 For more information on SVG, see the Worldwide Web Consortium's SVG web
62 page ⟨http://www.w3.org/Graphics/SVG/⟩ .
63
67 In addition to the options common to all programs based on libnetpbm
68 (most notably -quiet, see
69 Common Options ⟨index.html#commonoptions⟩ ), pamtosvg recognizes the
70 following command line options:
71 -background-color=colorname
75 Treat the specified color as the background color and ignore it.
76 If you don't specify this option, pamtosvg does not recognize
78 any background color.
79 Specify the color (colorname) as described for the argument of
81 the pnm_parsecolor() library routine
82 ⟨libnetpbm_image.html#colorname⟩ .
83 -centerline
86 Trace an object's centerline.
87 By default, pamtosvg traces an object's outline.
89 -corner-always-threshold=angle
92 Consider any angle at a pixel which falls below angle angle (in
93 decimal floating point degrees) as a corner, even if it is bor‐
94 dered by other corner pixels. Default is 60 degrees.
95 -corner-surround=integer
98 Consider the specified number of pixels on either side of a
99 point when determining if that point is a corner. Default is 4.
100 -corner-threshold=angle
103 Consider any pixel which forms an angle with its predecessors
104 and successors that is smaller than angle (in decimal floating
105 point degrees) as a corner. Default is 100.
106 -error-threshold=float
109 Subdivide fitted curves that are offset by a number of pixels
110 exceeding the specified number. Default is 2.0.
111 -filter-iterations=integer
114 Smooth the curve the specified number of times prior to fitting
115 Default is 4.
116 -line-reversion-threshold=float
119 When a spline is closer to a straight line than the specified
120 real number weighted by the square of the curve length, maintain
121 it as a straight line, even if it is a list with curves.
122 Default is .01.
124 -line-threshold=float
127 If a spline does not deviate from the straight line defined by
128 its endpoints by more than the specified number of pixels, then
129 treat it as a straight line.
130 Default is 1.
132 -log Create a log of the curve tracing process (suitable for debug‐
135 ging). Put it in the file named inputfile.log in the current
136 directory, where inputfile is the root of the input file name,
137 or "pamtosvg" if the input is from Standard Input or a file with
138 a weird name.
139 -preserve-width
142 Preserve line width prior to thinning. Meaningful only with
143 -centerline.
144 remove-adjacent-corners
147 Remove adjacent corners.
148 -report-progress
151 Report the progress of the tracing to Standard Error as it hap‐
152 pens.
153 -tangent-surround
156 Consider the specified number of points to either side of a
157 point when computing the tangent at that point. Default is 3.
158 -width-weight-factor
161 Weight factor for fitting the linewidth.
162
167 A convenient way to view an SVG document is with a web browser. Many
168 understand a file whose name ends in ".svg" to be an SVG image and can
169 render it.
170
174 pnmquant(1), pbmclean(1), pnm(1), Autotrace
175 ⟨http://autotrace.sourceforge.net⟩
176
179 pamtosvg was added to Netpbm in Version 10.33 (March 2006).
180 The core of pamtosvg -- the curve tracing logic -- was taken nearly
182 unmodified from Martin Weber's Autotrace program. That program dupli‐
183 cates a lot of Netpbm function, so pamtosvg is a much leaner program.
184 Bryan Henderson created pamtosvg, basically just by adapting Autotrace
186 to Netpbm.
187 Autotrace was first released in 2000 and updates were released through
189 2002. A number of people wrote the code in it, but Masatake Yamato and
190 Martin Weber appear to be the principal creators of it.
191 As of June 2006, there was a Sourceforge project
193 ⟨http://autotrace.sourceforge.net⟩ for it.
194
196 This manual page was generated by the Netpbm tool 'makeman' from HTML
197 source. The master documentation is at
198 http://netpbm.sourceforge.net/doc/pamtosvg.html
200netpbm documentation 23 April 2006 Pamtosvg User Manual(0)