Pbmtext User Manual(0) Pbmtext User Manual(0)NAMEpbmtext - render text into a PBM image
SYNOPSISpbmtext [-font fontfile] [-builtin fontname] [-space pixels] [-lspace
pixels] [-nomargins] [-width pixels] [text]
Minimum unique abbreviation of option is acceptable. You may use dou‐
ble 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)pbmtext takes the specified text, either a single line from the command
line or multiple lines from standard input, and renders it into a PBM
graphical image.
In the image, each line of input is a line of output. Formatting char‐
acters such as newline have no effect on the formatting; like any
unprintable character, they turn into spaces.
The image is just wide enough for the longest line of text, plus mar‐
gins, and just high enough to contain the lines of text, plus margins.
The left and right margins are twice the width of the widest character
in the font; the top and bottom margins are the height of the tallest
character in the font. But if the text is only one line, all the mar‐
gins are half of this. You can use the -nomargins option to eliminate
the margins.
pbmtextps does the same thing as pbmtext, but uses Ghostscript to gen‐
erate the characters, which means you can use Postscript fonts. But it
also means you have to have Ghostscript installed and it isn't as fast.
Also, pbmtextps generates only one line of text, whereas pbmtext can
create multiple lines.
pbmtext is meant for small quantities of simple text. If you're work‐
ing with a document, you would be better off using a document format‐
ting program to 'print' to a Postscript file, then feeding that Post‐
script to pstopnm.
OPTIONS-font
-builtin
-builtin selects a font among those built into Netpbm.
-font selects a font that you supply yourself either as an X
Window System BDF (Bitmap Distribution Format)
⟨http://xfree86.org/current/bdf.pdf⟩ file or as a PBM file in a
special form.
The default is the built in font 'bdf.'
'bdf' is Times-Roman 15 pixels high. (That's about 14 point
type printed at 75 dpi).
'fixed' is a built in fixed width font.
For information about other fonts, and how to make one of your
own, see Fonts ⟨#fonts⟩ below.
-space pixels
Add pixels pixels of space between characters. This is in
addition to whatever space surrounding characters is built into
the font, which is usually enough to produce a reasonable string
of text.
pixels may be fractional, in which case the number of pixels
added varies so as to achieve the specified average. For exam‐
ple -space=1.5 causes half the spaces to be 1 pixel and half to
be 2 pixels.
pixels may be negative to crowd text together, but the author
has not put much thought or testing into how this works in every
possible case, so it might cause disastrous results.
-lspace pixels
Add pixels pixels of space between lines. This is in addition
to whatever space above and below characters is built into the
font, which is usually enough to produce a reasonable line spac‐
ing.
pixels must be a whole number.
pixels may be negative to crowd lines together, but the author
has not put much thought or testing into how this works in every
possible case, so it might cause disastrous results.
-nomargins
By default, pbmtext adds margins all around the image as
described above. This option causes pbmtext not to add any mar‐
gins.
Note that there may still be space beyond the edges of the type
because a character itself may include space at its edges. To
eliminate all surrounding background, so the type touches all
four edges of the image, use pnmcrop.
-width pixels
This specifies how much horizontal space the text is supposed to
fit into.
If the input is one line, pbmtext breaks it into multiple lines
as needed to fit the specified width. It breaks it between
characters, but does not pay attention to white space; it may
break in the middle of a word and a line may begin or end with
white space.
If the input is multiple lines, pbmtext assumes you already have
line breaks where they make sense, and pbmtext simply truncates
each line as needed to fit the specified width.
USAGE
Often, you want to place text over another image. One way to do this
is with ppmlabel. For more flexible (but complex) drawing of text on
an image, there is ppmdraw. These do not give you the font options
that pbmtext does, though.
Another way is to use pbmtext to create an image containing the text,
then use pamcomp to overlay the text image onto your base image. To
make only the text (and not the entire rectangle containing it) cover
the base image, you will need to give pamcomp a mask, via its -alpha
option. You can just use the text image itself as the mask, as long as
you also specify the -invert option to pamcomp.
If you want to overlay colored text instead of black, just use ppm‐
change to change all black pixels to the color of your choice before
overlaying the text image. But still use the original black and white
image for the alpha mask.
If you want the text at an angle, use pnmrotate on the text image (and
alpha mask) before overlaying.
FONTS
There are three kinds of fonts you an use with pbmtext:
· built in
· BDF
· PBM
Built In Fonts
There are two built in fonts: bdf and fixed. You select these fonts
with a -builtin option.
bdf is the default when you specify no font information on the command
line.
bdf is encoded in ISO 8859-1 (Latin 1, 8-bit). In addition to English
it can handle most West European languages (Spanish, French, German,
Swedish ...) This set lacks the Euro currency sign.
fixed is ASCII (7-bit) only.
BDF Font
BDF is an ancient font format that at one time was standard for the X
Window System. Now, you don't see it very often, but you can find some
BDF fonts on the Xfree86
⟨http://cvsweb.xfree86.org/cvsweb/xc/fonts/bdf/⟩ web site.
You can get the full package of the BDF fonts from XFree86 (see above)
from the Netpbm web site ⟨http://netpbm.sourceforge.net/bdffont.tgz⟩ .
PBM Font
To create a font as a PBM file (to use with the -font option), you just
create a PBM image of the text matrix below.
The first step is to display text matrix below on the screen, e.g. in
an X11 window.
M ',/^_[`jpqy| M
/ !'#$%&'()*+ /
< ,-./01234567 <
> 89:;<=>?@ABC >
@ DEFGHIJKLMNO @
_ PQRSTUVWXYZ[ _
{ \]^_`abcdefg {
} hijklmnopqrs }
~ tuvwxyz{|}~ ~
M ',/^_[`jpqy| M
Make sure it's a fixed width font -- This should display as a perfect
rectangle.
Also, try to use a simple display program. Pbmtext divides this into a
matrix of cells, all the same size, each containing one character, so
it is important that whatever you use to display it display with uni‐
form horizontal and vertical spacing. Fancy word processing programs
sometimes stretch characters in both directions to fit certain dimen‐
sions, and that won't work. Sometimes a display program scales a font
to show a character larger or smaller than its natural size. That too
won't often work because the rounding involved in such scaling causes
non-uniform distances between characters.
If you display the text matrix improperly, the usual symptom is that
when you try to use the font, pbmtext fails with an error message
telling you that the number of lines in the font isn't divisible by 11,
or it can't find the blank band around the inner rectangle. Sometimes
the symptom is that one of the characters displays with a piece of the
character that is next to it in the matrix. For example, 'l' might
display with a little piece of the 'm' attached on its right.
Do a screen grab or window dump of that text, using for instance xwd,
xgrabsc, or screendump. Convert the result into a pbm file. If neces‐
sary, use pamcut to remove anything you grabbed in addition to the text
pictured above (or be a wimp and use a graphical editor such as
ImageMagick). Finally, run it through pnmcrop. to make sure the edges
are right up against the text. pbmtext can figure out the sizes and
spacings from that.
NON-ENGLISH TEXT
pbmtext does little to accommodate the special needs of non-English
text.
pbmtext reads input in byte units. Unicode (utf-7, utf-8, utf-16,
etc.) text which contains multibyte characters does not work.
pbmtext can handle 7-bit and 8-bit character sets. Examples are ASCII,
ISO 8859 family, koi8-r/u and VISCII. It is up to the user to supply a
BDF file covering the necessary glyphs with the "-font" option. The
font file must be in the right encoding.
pbmtext does not recognize locale. It ignores the associated environ‐
ment variables.
pbmtext cannot render vertically or right to left.
TIPS
If you get garbled output, check whether the font file encoding corre‐
sponds to the input text encoding. Also make sure that your input is
not in utf-* or any other multi-byte format.
To dump characters in a BDF font file run this command:
$ awk 'BEGIN { for (i=0x01; i<=0xFF; i++)
{ printf('%c%s',i,i%16==15 ? '\n':''); } }' |\
pbmtext-f font.bdf > dump.pbm
If you need only ASCII, change the for statement to:
for (i=0x20; i<=0x7E; i++)
To check the encoding of a BDF file, examine the CHARSET_REGISTRY line
and the next line, which should be CHARSET_ENCODING:
$ grep -A1 CHARSET_REGISTRY font-a.bdf
CHARSET_REGISTRY 'ISO8859'
CHARSET_ENCODING '1'
$ grep -A1 CHARSET_REGISTRY font-b.bdf
CHARSET_REGISTRY 'ISO10646'
CHARSET_ENCODING '1'
The latter is Unicode. BDF files coded in ISO 16046-1 usually work for
Western European languages, because ISO 16046-1 expands ISO 8859-1
(also called 'Latin-1') while maintaining the first 256 code points.
ISO 8859-1 itself is a superset of ASCII. Run the above command and
verify the necessary glyphs are present.
It may sound strange that pbmtext accepts font files encoded in Unicode
but not input text in Unicode. This is because Unicode provides sev‐
eral 'numbering schemes'.
When rendering text in character sets other than ISO 8859-1, one often
has to produce a BDF file in the given encoding from a master BDF file
encoded in ISO 10646-1.
In particular, 75% of the BDF files in the font collection available
from the Netpbm website ⟨http://netpbm.sourceforge.net/bdffont.tgz⟩
are in ISO 10646-1. Many have the Euro sign, Greek letters, etc, but
they are placed in code points beyond what pbmtext sees.
There are several programs that perform BDF encoding conversion. If
you have the X Window System installed, first look for ucs2any. If you
don't, you can download ucs2any.pl from Unicodefontsandtools for X11
(1)
Another converter is trbdf, included in the 'trscripts' package, avail‐
able in some GNU/Linux distributions.
BDF files encoded in ISO 8859-2, ISO 8859-7, koi8-r, etc. are available
from ISO8859Alphabet Soup (1)
and its sister page TheCyrillicCharset Soup (1) of 8-bit character
sets.
To convert OTF or TTF font files to BDF, use
otf2bdf by Mike Leisher
⟨http://www.math.nmsu.edu/~mleisher/Software/otf2bdf⟩ .
SEE ALSOpbmtextps(1) , pamcut(1) , pnmcrop(1) , pamcomp(1) , ppmchange(1) ,
pnmrotate(1) , ppmlabel(1) , ppmdraw(1) , pstopnm(1) , pbm(1) , Pango
⟨http://www.pango.org⟩ , Cairo ⟨http://cairographics.org⟩
AUTHOR
Copyright (C) 1993 by Jef Poskanzer and George Phillips
netpbm documentation 14 June 2010 Pbmtext User Manual(0)
