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File: dvipng.info, Node: Top, Next: Introduction, Up: (dir)
dvipng
******
This manual documents dvipng, a program to translate a DVI (DeVice
Independent) file into PNG (Portable Network Graphics).
This file documents dvipng version 1.14
Corrections or perhaps rewrites of sections are _very welcome_.
Jan-AAke Larsson
* Menu:
* Introduction:: Introduction
* Installation:: How to compile and install dvipng
* Basic usage:: First things first
* Command-line options:: Advanced usage
* Graphics:: Including PostScript and/or bitmaps
* Color:: Using color with dvipng
* Diagnosing problems:: Problems?
* Credits:: People who have contributed
* Copying:: GNU Lesser General Public License
* Index:: General index
File: dvipng.info, Node: Introduction, Next: Installation, Prev: Top, Up: Top
1 Introduction
**************
This program makes PNG and/or GIF graphics from DVI files as obtained
from TeX and its relatives.
If GIF support is enabled, GIF output is chosen by using the
`dvigif' binary or with the `--gif' option.
It is intended to produce anti-aliased screen-resolution images as
fast as is possible. The target audience is people who need to generate
and regenerate many images again and again. The primary target is the
preview-latex (X)Emacs package, a package to preview formulas from
within (X)Emacs. Yes, you get to see your formulas in the (X)Emacs
buffer, see `http://www.gnu.org/software/auctex/preview-latex.html'.
Another example is WeBWorK, an internet-based method for delivering
homework problems to students over the internet, giving students
instant feedback as to whether or not their answers are correct, see
`http://webwork.math.rochester.edu'.
A more recent addition to the dvipng-using applications out there is
MediaWiki, the software behind Wikipedia and many other wikis out
there. Dvipng is used to render mathematical formulae from version
1.8.0 of MediaWiki, see `http://www.mediawiki.org'.
Other applications may also benefit, like web applications as
latex2html and WYSIWYG editors like LyX.
The benefits of `dvipng'/`dvigif' include
* Speed. It is a very fast bitmap-rendering code for DVI files, which
makes it suitable for generating large amounts of images
on-the-fly, as needed in preview-latex, WeBWorK and others.
* It does not read the postamble, so it can be started before TeX
finishes. There is a `--follow' switch that makes dvipng wait at
end-of-file for further output, unless it finds the POST marker
that indicates the end of the DVI.
* Interactive query of options. dvipng can read options interactively
through stdin, and all options are usable. It is even possible to
change the input file through this interface.
* Supports PK, VF, PostScript Type1, and TrueType fonts, subfonts
(i.e., as used in CJK-LaTeX), color specials, and inclusion of
PostScript, PNG, JPEG or GIF images.
* and more...
File: dvipng.info, Node: Installation, Next: Basic usage, Prev: Introduction, Up: Top
2 Installation
**************
Installing dvipng should be simple: merely `./configure', `make', and
`make install'.
* Menu:
* Prerequisites::
* Configure::
* Build/install::
* Installation outside the texmf tree::
* Advice for non-privileged users::
File: dvipng.info, Node: Prerequisites, Next: Configure, Up: Installation
2.1 Prerequisites
=================
* The GD Graphics Draw library, libgd
The drawing library `libgd' is necessary, and is downloadable at
`http://www.boutell.com/gd', and there are binary packages for
most operating systems from their respective distributors. In any
case, the latest version of the library installs using `autoconf'
so it should not be difficult for you to install it from source,
and then proceed with installing dvipng.
* The path-searching library kpathsea
Kpathsea is most likely included in your LaTeX installation, but it
may happen that ./configure does not find it; see below. If you do
not have it, download it from `http://www.ctan.org' and compile it.
I have no experience with this, so I cannot help much here.
* The font-rendering library FreeType 2
While not strictly necessary, a recent FreeType 2 is recommended
since dvipng currently will produce better-quality images when
this library is available. To take advantage of this, you should
have at least FreeType 2.1.9.
FreeType 2 will enable direct support for PostScript and TrueType
fonts, so that dvipng will not need to generate bitmapped variants
on disk of the TeX fonts since modern TeX distributions include
PostScript versions of them. Then, you can render images at
different (and unusual) resolutions without cluttering the disk
with lots of bitmapped fonts.
Finally, it will enable subfont support in dvipng. That is, if you
want to render CJK-LaTeX characters, you must have FreeType 2
installed.
* The font-rendering library T1lib
An alternative to FreeType 2 is T1lib, but this will enable only
PostScript fonts in dvipng and will not include subfont support.
Also here, you can render images at different (and unusual)
resolutions without cluttering the disk with lots of bitmapped
fonts. If both FreeType 2 and T1lib are present, FreeType will be
internally preferred by dvipng but T1lib can be chosen at runtime.
* libpng and libz
To be able to compress and write PNG files to disk, dvipng (or
really libgd) uses libpng which in turn uses libz. These should be
available on any modern system, if not, download them and install
them.
* The `texinfo' package
This is needed for building the documentation.
File: dvipng.info, Node: Configure, Next: Build/install, Prev: Prerequisites, Up: Installation
2.2 Configure
=============
The first step is to configure the source code, telling it where
various files will be. To do so, run
./configure OPTIONS
(Note: if you have fetched dvipng from CVS rather than a regular
release, you will have to first generate `./configure' by running
`autoconf' 2.53 or later.)
On many machines, you will not need to specify any options, but if
`configure' cannot determine something on its own, you'll need to help
it out. For a list of the options type
./configure --help
On some machines, the libraries will be installed in directories that
are not in the linker's search path. This will generate an error when
running `./configure', indicating that it cannot find libgd or
libkpathsea (most likely). You then need to specify the path to the
respective library's object files. They are typically called e.g.,
`libgd.a' or `libgd.so'. If they are located in e.g., `/sw/local/lib',
do
./configure LDFLAGS=-L/sw/local/lib
If the library is available as a shared object file (`.so'), the
runtime linker may also need to be told where to find the library, then
use
./configure LDFLAGS='-L/sw/local/lib -R/sw/local/lib'
When either of these is necessary, it is likely that the C header
files are also installed in directories that are not in the C
preprocessor's search path. This will also generate an error when
running `./configure', indicating that it cannot find e.g., `gd.h' or
`kpathsea.h' (most likely). You then need to specify the path to the
respective library's C header files. If they are located in e.g.,
`/sw/local/include', do
./configure CPPFLAGS=-I/sw/local/include
On my SUN Solaris workstation, I had to combine this into
./configure CPPFLAGS='-I/sw/local/include -I/sw/tex/teTeX/1.0/include'\
LDFLAGS='-L/sw/local/lib -R/sw/local/lib -L/sw/tex/teTeX/1.0/lib/'
where the backslash denotes a continuation of the line.
File: dvipng.info, Node: Build/install, Next: Installation outside the texmf tree, Prev: Configure, Up: Installation
2.3 Build/install
=================
Once `configure' has been run, simply enter
make
at the prompt to compile the C code, and build the documentation files.
To install the files into the locations chosen earlier, type
make install
You may need special privileges to install, e.g., if you are installing
into system directories.
File: dvipng.info, Node: Installation outside the texmf tree, Next: Advice for non-privileged users, Prev: Build/install, Up: Installation
2.4 Installation outside the texmf tree
=======================================
In some cases, a dvipng binary installed outside the texmf tree will
not be able to find virtual fonts, or the PostScript font maps
(normally used by dvips). This may be because _only_ $SELFAUTOLOC,
$SELFAUTODIR, and $SELFAUTOPARENT are used in the texmf tree
configuration file `texmf.cnf'. If so, give the switch
`--enable-selfauto-set' to `./configure'. This will make dvipng adjust
these three internally so that kpathsea thinks that dvipng _is_
installed in the texmf tree.
File: dvipng.info, Node: Advice for non-privileged users, Prev: Installation outside the texmf tree, Up: Installation
2.5 Installation for non-privileged users
=========================================
Often people without system administration privileges want to install
software for their private use. In that case you need to specify more
options to the `configure' script, usually this is done by using the
`--prefix' option to the `configure' script, and let it point to the
personal home directory. In that way, resulting binaries will be
installed under the `bin' subdirectory of your home directory, manual
pages under `man' and so on. That way, it is reasonably easy to
maintain a bunch of additional packages, since the prefix argument is
supported by most `configure' scripts.
You'll have to add something like `/home/myself/bin' to your `PATH'
shell variable, if it isn't there already, and similarly set the
`INFOPATH' and `MANPATH' variables to be able to access the
documentation.
File: dvipng.info, Node: Basic usage, Next: Command-line options, Prev: Installation, Up: Top
3 Basic usage of dvipng
***********************
To use dvipng at its simplest, simply type
dvipng foo
where `foo.dvi' is the output of TeX that you want to convert to PNG
format. If there are four pages in `foo.dvi', those pages will be
output as `foo1.png', `foo2.png', `foo3.png', and `foo4.png',
respectively.
If you have enabled the PostScript font support (via FreeType or
T1lib), fonts will be rendered as they are needed. Otherwise, dvipng
will use bitmapped (PK) fonts, and if you use PK fonts that have not
been used on your system before, they may be automatically generated;
this process can take a few minutes, so progress reports appear by
default. The next time the same font is used, it will have been saved
on disk, so rendering will go much faster. (If dvipng tries to
endlessly generate the same fonts over and over again, something is
wrong. *Note Unable to generate fonts: (kpathsea)Unable to generate
fonts.)
Many options are available (see the next section). For a brief
summary of available options, just type
dvipng --help
File: dvipng.info, Node: Command-line options, Next: Graphics, Prev: Basic usage, Up: Top
4 Command-line options
**********************
dvipng has a plethora of command line options. Reading through this
section will give a good idea of the capabilities of the driver.
* Menu:
* Option summary:: Quick listing, from dvipng --help.
* Option details:: More information about each option.
File: dvipng.info, Node: Option summary, Next: Option details, Up: Command-line options
4.1 Option summary
==================
Here is a handy summary of the options; it is printed out when you run
dvipng with no arguments or with the standard `--help' option.
This is ./dvipng 1.14 Copyright 2002-2010 Jan-Ake Larsson
Usage: ./dvipng [OPTION]... FILENAME[.dvi]
Options are chosen to be similar to dvips' options where possible:
-d # Debug (# is the debug bitmap, 1 if not given)
-D # Output resolution
-l # Last page to be output
-o f Output file, '%d' is pagenumber
-O c Image offset
-p # First page to be output
-pp #,#.. Page list to be output
-q* Quiet operation
-T c Image size (also accepts '-T bbox' and '-T tight')
-v* Verbose operation
- Interactive query of options
These do not correspond to dvips options:
-bd # Transparent border width in dots
-bd s Transparent border fallback color (TeX-style color)
-bg s Background color (TeX-style color or 'Transparent')
--depth* Output the image depth on stdout
--dvinum* Use TeX page numbers in output filenames
-fg s Foreground color (TeX-style color)
--follow* Wait for data at end-of-file
--freetype* FreeType font rendering (preferred, default on)
--gamma # Control color interpolation
--gif Output GIF images (dvigif default)
--height* Output the image height on stdout
--nogs* Don't use ghostscript for PostScript specials
--nogssafer* Don't use -dSAFER in ghostscript calls
--norawps* Don't convert raw PostScript specials
--palette* Force palette output
--picky When a warning occurs, don't output image
--png Output PNG images (dvipng default)
--strict When a warning occurs, exit
--t1lib* T1lib font rendering (default on)
--truecolor* Truecolor output
-Q # Quality (T1lib and PK subsampling)
--width* Output the image width on stdout
-z # PNG compression level
# = number f = file s = string * = suffix, '0' to turn off
c = comma-separated dimension pair (e.g., 3.2in,-32.1cm)
File: dvipng.info, Node: Option details, Prev: Option summary, Up: Command-line options
4.2 Option details
==================
Many of the parameterless options listed here can be turned off by
suffixing the option with a zero (`0'); for instance, to turn off page
reversal, use `-r0'. Such options are marked with a trailing `*'.
`-'
Read additional options from standard input after processing the
command line.
`--help'
Print a usage message and exit.
`--version'
Print the version number and exit.
`-bd NUM'
`-bd COLOR_SPEC'
`-bd 'NUM COLOR_SPEC''
Set the pixel width of the transparent border (default 0). Using
this option will make the image edges transparent, but it only
affects pixels with the background color. Giving a COLOR_SPEC will
set the fallback color, to be used in viewers that cannot handle
transparency (the default is the background color). The color spec
should be in TeX color \special syntax, e.g., 'rgb 1.0 0.0 0.0'.
Setting the fallback color makes the default border width 1 px.
*Note Color::.
`--bdpi NUM'
This option only has an effect when using bitmapped (PK) fonts. The
option sets the base (Metafont) resolution, both horizontal and
vertical, to NUM dpi (dots per inch). This option is necessary
when manually selecting Metafont mode with the -mode option (see
below).
`-bg COLOR_SPEC'
Choose background color for the images. This option will be
ignored if there is a background color \special in the DVI. The
color spec should be in TeX color \special syntax, e.g., 'rgb 1.0
0.0 0.0'. You can also specify 'Transparent' or 'transparent'
which will give you a transparent background with the normal
background as a fallback color. A capitalized 'Transparent' will
give a full-alpha transparency, while an all-lowercase
'transparent' will give a simple fully transparent background with
non-transparent antialiased pixels. The latter would be suitable
for viewers who cannot cope with a true alpha channel. GIF images
do not support full alpha transparency, so in case of GIF output,
both variants will use the latter behaviour. *Note Color::.
`-d NUM'
Set the debug flags, showing what dvipng (thinks it) is doing.
This will work unless dvipng has been compiled without the `DEBUG'
option (not recommended). Set the flags as you need them, use `-d
-1' as the first option for maximum output. *Note Debug options::.
`-D NUM'
Set the output resolution, both horizontal and vertical, to NUM
dpi (dots per inch).
One may want to adjust this to fit a certain text font size (e.g.,
on a web page), and for a text font height of FONT_PX pixels (in
Mozilla) the correct formula is
DPI = FONT_PX * 72.27 / 10 [px * TeXpt/in / TeXpt]
The last division by ten is due to the standard font height 10pt in
your document, if you use 12pt, divide by 12. Unfortunately, some
proprietary browsers have font height in pt (points), not pixels.
You have to rescale that to pixels, using the screen resolution
(default is usually 96 dpi) which means the formula is
FONT_PX = FONT_PT * 96 / 72 [pt * px/in / (pt/in)]
On some high-res screens, the value is instead 120 dpi. Good luck!
`--depth*'
Report the depth of the image. This only works reliably when the
LaTeX style `preview.sty' from preview-latex is used with the
`active' option. It reports the number of pixels from the bottom
of the image to the baseline of the image. This can be used for
vertical positioning of the image in, e.g., web documents, where
one would use (Cascading StyleSheets 1)
<IMG SRC="FILENAME.PNG" STYLE="vertical-align: -DEPTHpx">
The depth is a negative offset in this case, so the minus sign is
necessary, and the unit is pixels (px).
`--dvinum*'
Set this option to make the output page number be the TeX page
numbers rather than the physical page number. See the `-o' switch.
`-fg COLOR_SPEC'
Choose foreground color for the images. This option will be
ignored if there is a foreground color \special in the DVI. The
color spec should be in TeX color \special syntax, e.g., 'rgb 1.0
0.0 0.0'. *Note Color::.
`--follow*'
Wait for data at end-of-file. One of the benefits of dvipng is
that it does not read the postamble, so it can be started before
TeX finishes. This switch makes dvipng wait at end-of-file for
further output, unless it finds the POST marker that indicates the
end of the DVI. This is similar to `tail -f' but for DVI-to-PNG
conversion.
`--freetype*'
Enable/disable FreeType font rendering (default on). This option is
available if the FreeType2 font library was present at compilation
time. If this is the case, dvipng will have direct support for
PostScript Type1 and TrueType fonts internally, rather than using
`gsftopk' for rendering the fonts. If you have PostScript versions
of Computer Modern installed, there will be no need to generate
bitmapped (PK) variants on disk of these. Then, you can render
images at different (and unusual) resolutions without cluttering
the disk with lots of bitmapped fonts. Note that if you have both
FreeType and T1lib on your system, FreeType will be preferred by
dvipng. If you for some reason would want to use T1lib rendering,
use this option.
`--gamma NUM'
Control the interpolation of colors in the greyscale anti-aliasing
color palette. Default value is 1.0. For 0 < NUM < 1, the fonts
will be lighter (more like the background), and for NUM > 1, the
fonts will be darker (more like the foreground).
`--gif*'
The images are output in the GIF format, if GIF support is enabled.
This is the default for the `dvigif' binary, which only will be
available when GIF support is enabled. GIF images are palette
images (see the `--palette' option) and does not support true alpha
channels (see the `--bg' option). See also the `--png' option.
`--height*'
Report the height of the image. This only works reliably when the
LaTeX style `preview.sty' from preview-latex is used with the
`active' option. It reports the number of pixels from the top of
the image to the baseline of the image. The total height of the
image is obtained as the sum of the values reported from
`--height' and `--depth'.
`-l [=]NUM'
The last page printed will be the first one numbered NUM. Default
is the last page in the document. If NUM is prefixed by an equals
sign, then it (and the argument to the `-p' option, if specified)
is treated as a physical (absolute) page number, rather than a
value to compare with the TeX `\count0' values stored in the DVI
file. Thus, using `-l =9' will end with the ninth page of the
document, no matter what the pages are actually numbered.
`--mode MODE'
This option only has an effect when using bitmapped (PK) fonts. Use
MODE as the Metafont device name for the PK fonts (both for path
searching and font generation). This needs to be augmented with
the base device resolution, given with the `--bdpi' option. See
the file `ftp://ftp.tug.org/tex/modes.mf' for a list of
resolutions and mode names for most devices. *Note Unable to
generate fonts: (kpathsea)Unable to generate fonts.
`-M*'
This option only has an effect when using bitmapped (PK) fonts. It
turns off automatic PK font generation (`mktexpk').
`--nogs*'
This switch prohibits the internal call to GhostScript for
displaying PostScript specials. `--nogs0' turns the call back on.
`--nogssafer*'
Normally, if GhostScript is used to render PostScript specials, the
GhostScript interpreter is run with the option `-dSAFER'. The
`--nogssafer' option runs GhostScript without `-dSAFER'. The
`-dSAFER' option in Ghostscript disables PostScript operators such
as deletefile, to prevent possibly malicious PostScript programs
from having any effect.
`--norawps*'
Some packages generate raw PostScript specials, even non-rendering
such specials. This switch turns off the internal call to
GhostScript intended to display these raw PostScript specials.
`--norawps0' turns the call back on.
`-o NAME'
Send output to the file NAME. A single occurrence of `%d' or
`%01d', ..., `%09d' will be exchanged for the physical page number
(this can be changed, see the `--dvinum' switch). The default
output filename is `FILE%d.png' where the input DVI file was
`FILE.dvi'.
`-O X-OFFSET,Y-OFFSET'
Move the origin by X-OFFSET,Y-OFFSET, a comma-separated pair of
dimensions such as `.1in,-.3cm'. The origin of the page is
shifted from the default position (of one inch down, one inch to
the right from the upper left corner of the paper) by this amount.
`-p [=]NUM'
The first page printed will be the first one numbered NUM. Default
is the first page in the document. If NUM is prefixed by an
equals sign, then it (and the argument to the `-l' option, if
specified) is treated as a physical (absolute) page number, rather
than a value to compare with the TeX `\count0' values stored in the
DVI file. Thus, using `-p =3' will start with the third page of
the document, no matter what the pages are actually numbered.
`--palette*'
When an external image is included, `dvipng' will automatically
switch to truecolor mode, to avoid unnecessary delay and quality
reduction, and enable the EPS translator to draw on a transparent
background and outside of the boundingbox. This switch will force
palette (256-color) output and make `dvipng' revert to opaque
clipped image inclusion. This will also override the `--truecolor'
switch if present.
`--picky*'
No images are output when a warning occurs. Normally, dvipng will
output an image in spite of a warning, but there may be something
missing in this image. One reason to use this option would be if
you have a more complete but slower fallback converter. Mainly,
this is useful for failed figure inclusion and unknown \special
occurrences, but warnings will also occur for missing or unknown
color specs and missing PK fonts.
`--png*'
The images are output in the PNG format. This is the default for
the `dvipng' binary. See also the `--gif' option.
`-pp FIRSTPAGE-LASTPAGE'
Print pages FIRSTPAGE through LASTPAGE; but not quite equivalent
to `-p FIRSTPAGE -l LASTPAGE'. For example, when rendering a book,
there may be several instances of a page in the DVI file (one in
`\frontmatter', one in `\mainmatter', and one in `\backmatter').
In case of several pages matching, `-pp FIRSTPAGE-LASTPAGE' will
render _all_ pages that matches the specified range, while `-p
FIRSTPAGE -l LASTPAGE' will render the pages from the _first_
occurrence of FIRSTPAGE to the _first_ occurrence of LASTPAGE.
This is the (undocumented) behaviour of dvips. In dvipng you can
give both kinds of options, in which case you get all pages that
matches the range in `-pp' between the pages from `-p' to `-l'.
Also multiple `-pp' options accumulate, unlike `-p' and `-l'. The
`-' separator can also be `:'. Note that `-pp -1' will be
interpreted as "all pages up to and including 1", if you want a
page numbered -1 (only the table of contents, say) put `-pp -1--1',
or more readable, `-pp -1:-1'.
`-q*'
Run quietly. Don't chatter about pages converted, etc. to standard
output; report no warnings (only errors) to standard error.
`-Q NUM'
Set the quality to NUM. That is, choose the number of antialiasing
levels for bitmapped fonts (PK) and fonts rendered using T1lib, to
be NUM*NUM+1. The default value is 4 which gives 17 levels of
antialiasing for antialiased fonts from these two. If FreeType is
available, its rendering is unaffected by this option.
`-r*'
Toggle output of pages in reverse/forward order. By default, the
first page in the DVI is output first.
`--strict*'
The program exits when a warning occurs. Normally, dvipng will
output an image in spite of a warning, but there may be something
missing in this image. One reason to use this option would be if
you have a more complete but slower fallback converter. See the
`--picky' option above for a list of when warnings occur.
`-T IMAGE_SIZE'
Set the image size to IMAGE_SIZE which can be either of `bbox',
`tight', or a comma-separated pair of dimensions HSIZE,VSIZE such
as `.1in,.3cm'. The default is `bbox' which produces a PNG that
includes all ink put on the page and in addition the DVI origin,
located 1in from the top and 1in from the left edge of the paper.
This usually gives whitespace above and to the left in the
produced image. The value `tight' will make dvipng only include
all ink put on the page, producing neat images.
`--t1lib*'
Enable T1lib font rendering (default on). This option is available
if the T1lib font library was present at compilation time. If this
is the case, dvipng will have direct support for PostScript Type1
fonts internally, rather than using `gsftopk' for rendering the
fonts. If you have PostScript versions of Computer Modern
installed, there will be no need to generate bitmapped variants on
disk of these. Then, you can render images at different (and
unusual) resolutions without cluttering the disk with lots of
bitmapped fonts. Note that if you have both FreeType and T1lib on
your system, FreeType will be preferred by dvipng, and if you for
some reason rather want to use T1lib, give the option
`--freetype0' (see above).
`--truecolor*'
This will make `dvipng' generate truecolor output. Note that
truecolor output is automatic if you include an external image in
your DVI, e.g., via a PostScript special (i.e., the `graphics' or
`graphicx' package). This switch is overridden by the `--palette'
switch.
`-v*'
Enable verbose operation. This will currently indicate what fonts
is used, in addition to the usual output.
`--width*'
Report the width of the image. See also `--height' and `--depth'.
`-x NUM'
This option is deprecated; it should not be used. It is much
better to select the output resolution directly with the `-D'
option. This option sets the magnification ratio to NUM/1000 and
overrides the magnification specified in the DVI file. Must be
between 10 and 100000. It is recommended that you use standard
magstep values (1095, 1200, 1440, 1728, 2074, 2488, 2986, and so
on) to help reduce the total number of PK files generated. NUM
may be a real number, not an integer, for increased precision.
`-z NUM'
Set the PNG compression level to NUM. This option is enabled if
your `libgd' is new enough. The default compression level is 1,
which selects maximum speed at the price of slightly larger PNGs.
For an older `libgd', the hard-soldered value 5 is used. The
include file `png.h' says
Currently, valid values range from 0 - 9, corresponding
directly to the zlib compression levels 0 - 9 (0 - no
compression, 9 - "maximal" compression). Note that tests have
shown that zlib compression levels 3-6 usually perform as
well as level 9 for PNG images, and do considerably fewer
calculations. In the future, these values may not correspond
directly to the zlib compression levels.
File: dvipng.info, Node: Graphics, Next: Color, Prev: Command-line options, Up: Top
5 Graphics
**********
`dvipng' attempts to handle graphics as included by the `graphicx' and
`graphics' packages, without the need of specifying a driver to these
packages. This means that it recognizes the encapsulated postscript
inclusion meant for `dvips', but is also able (from version 1.8) to
include bitmapped graphics. It also tries to handle some of the raw
PostScript that is output from various packages. Some of the
possibilities and problems are mentioned below.
* Menu:
* Encapsulated PostScript:: An internal call to GhostScript
* Bitmapped graphics:: PNG, JPEG and GIF
* Raw PostScript:: Ignore or give to GhostScript
File: dvipng.info, Node: Encapsulated PostScript, Next: Bitmapped graphics, Up: Graphics
5.1 Encapsulated PostScript
===========================
When an EPS file is included, a call to GhostScript is performed to
produce a bitmapped image that can be included. The default is to
produce an image with transparent background, at the same size as the
DVI page currently being converted to PNG, and include that as
foreground on the PNG. Of course, if the image is to be cropped, that
is done. The included image will be a truecolor image, so for maximum
performance the output PNG will be in truecolor mode as well.
This conversion needs the `pngalpha' output device to be present in
your copy of GhostScript. If that device is not present, or you use the
`--palette' switch or request GIF output, the fallback is to use the
`png16m' device to produce a cropped opaque image for inclusion. Other
relevant switches are `--noghostscript' and `--nogssafer'. *Note Option
details::.
The most common problem with including graphics is an incorrect
bounding box. Complain to whoever wrote the software that generated the
file if the bounding box is indeed incorrect. An adjusted boundingbox
can be specified in the `\includegraphics' call, as in this example
(using `graphicx'):
\includegraphics[bb=10 20 100 200]{imagename.eps}
File: dvipng.info, Node: Bitmapped graphics, Next: Raw PostScript, Prev: Encapsulated PostScript, Up: Graphics
5.2 Bitmapped graphics
======================
dvipng can include PNG, JPEG and GIF graphics. When including such
images via `\includegraphics' you need to specify the bounding box
since TeX itself cannot read them from the files in question. The
bounding box size should be given as `0 0 w h' in pixels, e.g., if the
file `imagename.png' is 300x400 pixels, the inclusion would read
\includegraphics[bb=0 0 300 400]{imagename.png}
The default size is the image size in bp ("big points" in TeX
nomenclature or PostScript points as other people have it, 72 per inch).
That is, default resolution will be 72 dpi for included bitmaps, which
is the default size in the few other bitmap-capable drivers that are
known to me (dvipdfm and PDFLaTeX).
If you want 100 dpi you need to specify the width accordingly. You
just divide your image width by 100: a 135 pixel wide image at 100 dpi
will take up 1.35 inches. If you want 200 dpi you divide by 200, and so
on. Simple, eh? The example above at 200 dpi would be 1.5 inches wide:
\includegraphics[bb=0 0 300 400,witdh=1.5in]{imagename.png}
File: dvipng.info, Node: Raw PostScript, Prev: Bitmapped graphics, Up: Graphics
5.3 Raw PostScript
==================
dvipng attempts to handle raw PostScript. Rendering raw PostScript
specials is done on top of the page by including a transparent image
generated by the `pngalpha' device in GhostScript (automatically
selecting `truecolor' mode in dvipng).
Included PostScript headers are respected, and if the header
`tex.pro' is included, dvipng also throws in `color.pro' and
`special.pro'. The package `xcolor' includes its own headers with color
names, and this is not only kept as a PostScript header, but is also
read and interpreted by dvipng itself. An attempt is also made to
respect the PGF header. The non-rendering specials from `hyperref' are
handled via some heuristics and do not give an error.
Really rendering and moving things with raw PostScript specials is
more troublesome. The \rotatebox macro serves as a good example. The
dvips driver of the graphicx package surrounds DVI glyphs with
PostScript code so that after conversion by dvips, the glyphs (now
themselves in PostScript) will be rotated in the desired way. dvipng
does not handle this, at present. An attempt has been made to handle
the rendering specials output by PGF (tikz), and also PSTricks. Some
things work, but others do not. This is especially clear when mixing
PostScript and DVI rendering commands such as glyphs. dvipng cannot at
present detect if PostScript code moves `currentpoint' or rotates the
frame since GhostScript does not return such information. A
recommendation would be to produce images from these packages as EPS
files and include them into your document in the standard manner.
Another way to handle this would be to use a slower fallback (with
dvips and gs, for example). If you want to disable raw PostScript
handling in dvipng, use the switch `--norawps'. This switch turns off
the internal call to GhostScript intended to display these raw
PostScript specials. Further, when dvipng encounters raw PostScript and
the gs call is turned off, it gives a warning. It is now possible to
use the switch `--picky' to disable page rendering of pages with
warnings, and use the slower fallback for these pages.
File: dvipng.info, Node: Color, Next: Diagnosing problems, Prev: Graphics, Up: Top
6 Color
*******
To support color, dvipng recognizes a certain set of specials as
generated by the `color' and `xcolor' style files. These specials start
with the keyword `color' or the keyword `background', followed by a
color specification.
* Menu:
* Color specifications::
* Color specials::
File: dvipng.info, Node: Color specifications, Next: Color specials, Up: Color
6.1 Color specifications
========================
The color specification supported by dvipng is by-value or by-name. The
by-value spec starts with the name of a color model (one of `rgb',
`hsb', `cmy', `cmyk', or `gray') followed by the appropriate number of
parameters. Thus, the color specification `rgb 0.3 0.4 0.5' would
correspond to the color that is `0.3 0.4 0.5' in its red, blue and
green values. The color model used internally in dvipng is `RGB'
(discretized to 256 levels), for details on the formulas used in
conversion, see the `xcolor' documentation.
By-name color specifications are single (case-dependent) words and
are compared with color names defined in `dvipsnam.def' (from the
`graphics' bundle), `svgnam.def' and `xcolor.sty' (from the `xcolor'
bundle). See the `xcolor' documentation for a list of names and the
corresponding colors.
On the command-line, the name `Transparent' can also be used as an
argument to `--bg' to choose transparent background. *Note Option
details::.
File: dvipng.info, Node: Color specials, Prev: Color specifications, Up: Color
6.2 Color specials
==================
We will describe `background' first, since it is the simplest. The
`background' keyword must be followed by a color specification. That
color specification is used as a fill color for the background. The
last `background' special on a page is the one that gets used, and is
used for the whole of the page image. (This is possible because the
prescan phase of dvipng notices all of the color specials so that the
appropriate information can be written out during the second phase.)
The `color' special itself has three forms. The first is just
`color' followed by a color specification. In this case, the current
global color is set to that color; the color stack must be empty when
such a command is executed.
The second form is `color push' followed by a color specification.
This saves the current color on the color stack and sets the color to be
that given by the color specification. This is the most common way to
set a color.
The final form of the `color' special is just `color pop', with no
color specification; this says to pop the color last pushed on the
color stack from the color stack and set the current color to be that
color.
dvipng correctly handles these color specials across pages, even when
the pages are rendered repeatedly or in reverse order.
File: dvipng.info, Node: Diagnosing problems, Next: Credits, Prev: Color, Up: Top
7 Diagnosing problems
*********************
You've gone through all the trouble of installing dvipng, carefully read
all the instructions in this manual, and still can't get something to
work. The following sections provide some helpful hints if you find
yourself in such a situation.
* Menu:
* Contact information:: Who to ask.
* Debug options:: Getting diagnostics.
File: dvipng.info, Node: Contact information, Next: Debug options, Up: Diagnosing problems
7.1 Contact information
=======================
Bug reports should be sent to <dvipng AT nongnu.org>.
Questions, suggestions for new features, pleas for help, and/or
praise should go to <dvipng AT nongnu.org>. For more information on this
mailing list, send a message with just the word `help' as subject or
body to <dvipng-request AT nongnu.org> or look at
`http://lists.nongnu.org/mailman/listinfo/dvipng'.
Offers to support further development will be appreciated. For
developer access, ask on <dvipng AT nongnu.org>.
For details on the TeX path-searching library, and `mktexpk'
problems, *note Common problems: (kpathsea)Common problems.
File: dvipng.info, Node: Debug options, Prev: Contact information, Up: Diagnosing problems
7.2 Debug options
=================
The `-d' flag to dvipng helps in tracking down certain errors. The
parameter to this flag is an integer that tells what errors are
currently being tracked. To track a certain class of debug messages,
simply provide the appropriate number given below; if you wish to track
multiple classes, sum the numbers of the classes you wish to track. To
track all classes, you can use `-1'.
Some of these debugging options are actually provided by Kpathsea
(*note Debugging: (kpathsea)Debugging.).
The classes are:
1
Normal dvi op-codes
2
Virtual fonts
4
PK fonts
8
TFM files
16
Glyph rendering
32
FreeType calls
64
Encoding loads
128
Color specials
256
GhostScript specials
512
T1lib calls
1024
Kpathsea `stat' calls
2048
Kpathsea hash table lookups
4096
Kpathsea path element expansion
8192
Kpathsea path searches
File: dvipng.info, Node: Credits, Next: Copying, Prev: Diagnosing problems, Up: Top
8 Credits
*********
A number of persons have contributed, if I forget to mention someone, I
apologize. First and foremost we have David Kastrup whose preview-latex
project provided the incentive to write this program. There is also a
number of people who have contributed by reporting bugs and suggesting
improvements as the thing has evolved. These include but is perhaps not
limited to (in semi-random order): Thomas Esser (teTeX), Christian
Schenk (MIKTeX), Brian R Furry (debian package), Angus Leeming (LyX),
Thomas Boutell (libgd), John Jones (first user report), Uwe Kern
(xcolor), Karl Berry and Peter Breitenlohner (TeX Live), David Harvey
(hinting in Freetype), Neal Harmon, Alan Shutko, Reiner Stieb, Nick
Alcock, Adam Buchbinder, Svend Tollak Munkejord, James Longstreet,
Bernhard Simon, Bob McElrath, Georg Schwarz, Jason Farmer, Brian V.
Smith, Samuel Hathaway, Thomas R. Shemanske, Stephen Gibson, Christian
Ridderstro"m, Ezra Peisach, William H Wheeler, Thomas Klausner, Harald
Koenig, Adrian Bunk, Kevin Smith, Jason Riedy, Wolfram Krause, Reinhard
Kotucha, Takeshi Abe, and Waldeck Schutzer.
Use of the `gd' library requires inclusion of the following
copyright notice, which applies to the `gd' library:
Portions copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
2002, 2003, 2004 by Cold Spring Harbor Laboratory. Funded under
Grant P41-RR02188 by the National Institutes of Health.
Portions copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
2004 by Boutell.Com, Inc.
Portions relating to GD2 format copyright 1999, 2000, 2001, 2002,
2003, 2004 Philip Warner.
Portions relating to PNG copyright 1999, 2000, 2001, 2002, 2003,
2004 Greg Roelofs.
Portions relating to gdttf.c copyright 1999, 2000, 2001, 2002,
2003, 2004 John Ellson (ellson AT graphviz.org).
Portions relating to gdft.c copyright 2001, 2002, 2003, 2004 John
Ellson (ellson AT graphviz.org).
Portions relating to JPEG and to color quantization copyright
2000, 2001, 2002, 2003, 2004, Doug Becker and copyright (C) 1994,
1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Thomas
G. Lane. This software is based in part on the work of the
Independent JPEG Group. See the file README-JPEG.TXT for more
information.
Portions relating to GIF compression copyright 1989 by Jef
Poskanzer and David Rowley, with modifications for thread safety
by Thomas Boutell.
Portions relating to GIF decompression copyright 1990, 1991, 1993
by David Koblas, with modifications for thread safety by Thomas
Boutell.
Portions relating to WBMP copyright 2000, 2001, 2002, 2003, 2004
Maurice Szmurlo and Johan Van den Brande.
Portions relating to GIF animations copyright 2004 Jaakko
Hyva"dtti (jaakko.hyvatti AT iki.fi)
Permission has been granted to copy, distribute and modify gd in
any context without fee, including a commercial application,
provided that this notice is present in user-accessible supporting
documentation.
This does not affect your ownership of the derived work itself,
and the intent is to assure proper credit for the authors of gd,
not to interfere with your productive use of gd. If you have
questions, ask. "Derived works" includes all programs that utilize
the library. Credit must be given in user-accessible documentation.
This software is provided "AS IS." The copyright holders disclaim
all warranties, either express or implied, including but not
limited to implied warranties of merchantability and fitness for a
particular purpose, with respect to this code and accompanying
documentation.
Although their code does not appear in the current release, the
authors also wish to thank Hutchison Avenue Software Corporation
for their prior contributions.
File: dvipng.info, Node: Copying, Next: Index, Prev: Credits, Up: Top
9 Copying
*********
This program is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this program. If not, see
<http://www.gnu.org/licenses/>.
Copyright (C) 2002-2010 Jan-AAke Larsson
File: dvipng.info, Node: Index, Prev: Copying, Up: Top
Index
*****
[index]
* Menu:
* -dSAFER: Option details. (line 168)
* absolute page number, and -l: Option details. (line 142)
* absolute page number, and -p: Option details. (line 195)
* antialiasing levels, number of: Option details. (line 248)
* background color (option): Option details. (line 42)
* base resolution, setting: Option details. (line 35)
* baseline reporting: Option details. (line 78)
* color specifications: Color specifications.
(line 6)
* command-line options: Command-line options.
(line 6)
* compilation: Installation. (line 6)
* compression: Option details. (line 314)
* configuration, of dvipng: Installation. (line 6)
* dark fonts: Option details. (line 121)
* debugging <1>: Diagnosing problems. (line 6)
* debugging: Option details. (line 56)
* depth reporting: Option details. (line 78)
* exit on erroneous images: Option details. (line 259)
* first page printed: Option details. (line 195)
* follow mode: Option details. (line 99)
* font generation, avoiding: Option details. (line 160)
* forcing palette output: Option details. (line 204)
* foreground color (option): Option details. (line 93)
* FreeType font rendering: Option details. (line 107)
* fuzzy images: Option details. (line 121)
* gamma: Option details. (line 121)
* GhostScript and -dSAFER: Option details. (line 168)
* GhostScript, turning off: Option details. (line 164)
* GIF image format: Option details. (line 127)
* height reporting: Option details. (line 134)
* installation, of dvipng: Installation. (line 6)
* invoking dvipng: Basic usage. (line 6)
* last page printed: Option details. (line 142)
* light fonts: Option details. (line 121)
* magnification, overriding DVI: Option details. (line 304)
* Metafont mode, specifying: Option details. (line 151)
* mktexpk, avoiding: Option details. (line 160)
* mode name, specifying: Option details. (line 151)
* no erroneous images: Option details. (line 213)
* offset pages: Option details. (line 189)
* option, details of: Option details. (line 6)
* options, dvipng: Command-line options.
(line 6)
* options, reading from standard input: Option details. (line 11)
* options, summary: Option summary. (line 6)
* output resolution, setting: Option details. (line 62)
* output, redirecting: Option details. (line 182)
* page range: Option details. (line 226)
* page, first printed: Option details. (line 195)
* page, last printed: Option details. (line 142)
* physical page number, and -l: Option details. (line 142)
* physical page number, and -p: Option details. (line 195)
* PNG image format: Option details. (line 222)
* PostScript inclusion problems: Encapsulated PostScript.
(line 21)
* PostScript, turning off raw PostScript specials: Option details.
(line 176)
* problems: Diagnosing problems. (line 6)
* quality: Option details. (line 248)
* quiet operation: Option details. (line 244)
* reverse pagination: Option details. (line 255)
* silent operation: Option details. (line 244)
* standard input, reading options from: Option details. (line 11)
* standard output, output to: Option details. (line 182)
* T1lib font rendering: Option details. (line 276)
* transparent border fallback color: Option details. (line 25)
* transparent border width: Option details. (line 25)
* trouble: Diagnosing problems. (line 6)
* truecolor output: Option details. (line 290)
* warnings, suppressing: Option details. (line 244)
* width reporting: Option details. (line 301)
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