1Pamtosvg User Manual(0) Pamtosvg User Manual(0)
2
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
22 This program is part of Netpbm(1).
23 pamtosvg reads a PNM image as input and produce an SVG (Scalable Vector
25 Graphics) image as output. Thus, it traces curves in the input image
26 and creates a set of splines that represent the image.
27 SVG is a vector image format, which means it describes curves that com‐
29 pose an image. By contrast, PNM is a raster format, which means it
30 describes dots that compose an image. The main practical difference
31 between the two types is that you can scale vector images better. A
32 vector image also takes a lot less data to describe an image if the
33 image is composed of simple curves.
34 That means it is really an understatement to say that pamtosvg is an
36 image format converter. It's really an image tracer. Its main job is
37 to trace a raster image and find the lines in it. It then represents
38 its findings in SVG format.
39 pamtosvg does the same kind of thing that StreamLine, CorelTrace, and
41 Autotrace do. It is in fact derived from Autotrace.
42 SVG is a gigantic format, capable of amazing things. pamtosvg exploits
44 only a morsel of it. The SVG image produced by pamtosvg consists of a
45 single <svg> element, which has a 'width' attribute and a 'height'
46 attribute. The value of that element is composed of <path> elements.
47 That's it.
48 In the SVG output, distances are unitless, with one unit corresponding
50 to one pixel of the input.
51 So that pamtosvg will find simple curves in the image, you may want to
53 remove speckles from it with pbmclean and consolidate multiple shades
54 into single colors with pnmquant first.
55 For more information on SVG, see the Worldwide Web Consortium's SVG web
57 page ⟨http://www.w3.org/Graphics/SVG/⟩ .
58
62 Minimum unique abbreviation of option is acceptable. You may use dou‐
63 ble hyphens instead of single hyphen to denote options. You may use
64 white space in place of the equals sign to separate an option name from
65 its value.
66 -background-color=colorname
70 Treat the specified color as the background color and ignore it.
71 If you don't specify this option, pamtosvg does not recognize
73 any background color.
74 Specify the color (colorname) as described for the argument of
76 the ppm_parsecolor() library routine ⟨libppm.html#colorname⟩ .
77 -centerline
80 Trace an object's centerline.
81 By default, pamtosvg traces an object's outline.
83 -corner-always-threshold=angle
86 Consider any angle at a pixel which falls below angle angle (in
87 decimal floating point degrees) as a corner, even if it is bor‐
88 dered by other corner pixels. Default is 60 degrees.
89 -corner-surround=integer
92 Consider the specified number of pixels on either side of a
93 point when determining if that point is a corner. Default is 4.
94 -corner-threshold=angle
97 Consider any pixel which forms an angle with its predecessors
98 and successors that is smaller than angle (in decimal floating
99 point degrees) as a corner. Default is 100.
100 -error-threshold=float
103 Subdivide fitted curves that are offset by a number of pixels
104 exceeding the specified number. Default is 2.0.
105 -filter-iterations=integer
108 Smooth the curve the specified number of times prior to fitting
109 Default is 4.
110 -line-reversion-threshold=float
113 When a spline is closer to a straight line than the specified
114 real number weighted by the square of the curve length, maintain
115 it as a straight line, even if it is a list with curves.
116 Default is .01.
118 -line-threshold=float
121 If a spline does not deviate from the straight line defined by
122 its endpoints by more than the specified number of pixels, then
123 treat it as a straight line.
124 Default is 1.
126 -log Send a detailed progress report to the file named inputfile.log,
129 where inputfile is the root of the input file name, or 'pam‐
130 tosvg' if the input is from Standard Input or a file with a
131 weird name.
132 -preserve-width
135 Preserve line width prior to thinning. Meaningful only with
136 -centerline.
137 remove-adjacent-corners
140 Remove adjacent corners.
141 -report-progress
144 Report the progress of the tracing to Standard Error as it hap‐
145 pens.
146 -tangent-surround
149 Consider the specified number of points to either side of a
150 point when computing the tangent at that point. Default is 3.
151 -width-weight-factor
154 Weight factor for fitting the linewidth.
155
161 pnmquant(1), pbmclean(1), pnm(1), Autotrace
162 ⟨http://autotrace.sourceforge.net⟩
163
166 pamtosvg was added to Netpbm in Version 10.33 (March 2006).
167 The core of pamtosvg -- the curve tracing logic -- was taken nearly
169 unmodified from Martin Weber's Autotrace program. That program dupli‐
170 cates a lot of Netpbm function, so pamtosvg is a much leaner program.
171 Bryan Henderson created pamtosvg, basically just by adapting Autotrace
173 to Netpbm.
174 Autotrace was first released in 2000 and updates were released through
176 2002. A number of people wrote the code in it, but Masatake Yamato and
177 Martin Weber appear to be the principal creators of it.
178 As of June 2006, there was a Sourceforge project
180 ⟨http://autotrace.sourceforge.net⟩ for it.
181netpbm documentation 23 April 2006 Pamtosvg User Manual(0)