DVI (TeX Device Independent)

DVI is the output of classic TeX: tex and latex (in DVI mode), uplatex, ptex and lualatex --output-format=dvi. A DVI file lists, page by page, which character of which font goes where, plus black rectangles (rules). It doesn’t contain the fonts or any images; those are found on the system when the file is displayed or converted. That makes DVI files small and fast to produce, but they only display correctly on a machine with a TeX installation.

Today DVI is mostly an intermediate format: latex writes DVI, then dvipdfmx or dvips converts it to PDF or PostScript. Some workflows still use it because it compiles faster than pdflatex, and because latex + dvips handles PostScript-based packages (PSTricks). For sharing, convert to PDF.

When to use DVI#

• Use as an intermediate step: latex → DVI → dvipdfmx (PDF), dvips (PostScript), dvisvgm (SVG for the web) or dvipng (PNG, e.g. formula images).
• Use for fast preview while editing a large LaTeX document, with a viewer that reloads the file.
• Avoid for sending documents: the receiver needs the same fonts and image files. Send PDF.
• Avoid when you need Unicode text extraction or search: DVI stores font character codes, not text.

File structure#

A DVI file is a sequence of one-byte commands (opcodes), each followed by its parameters. Numbers are big-endian; distances are signed, in DVI units defined in the preamble (for TeX, scaled points: 1 pt = 65536 sp, 72.27 pt = 1 inch). The interpreter keeps a current position (h, v), four spacing registers (w, x, y, z), a stack for them, and a current font.

The file has 3 parts:

1. Preamble: pre (247), DVI version i (2), unit numerator and denominator, magnification, and a comment.
2. Pages: each starts with bop (139) and ends with eop (140). bop has the ten TeX page counters \count0-\count9 and a pointer to the previous bop, so pages form a linked list from the end.
3. Postamble: post (248) with a pointer to the last page, maximum page height and width, stack depth and page count, then all font definitions again, then post_post (249), a pointer to post, the version byte, and four to seven DF (223) bytes.

A reader can start at the end: skip the DF bytes, read the pointer to post, and get the page count and fonts without reading every page.

F7 02                     pre, DVI version 2
01 83 92 C0               num = 25400000
1C 3B 00 00               den = 473628672   (units are scaled points)
00 00 03 E8               mag = 1000 (no magnification)
1B                        comment length 27
20 54 65 58 20 6F 75 74   " TeX output 2026.11.05:1200"
...
8B                        bop (first page)

Opcodes#

Fonts#

A font definition names a TeX font (for example cmr10) and its size. The DVI file doesn’t contain the font: a driver reads the font metrics from cmr10.tfm, then finds the glyph shapes, either a PK bitmap font or an outline (Type 1, OpenType) font through map files such as pdftex.map. TeX installations look these files up with the kpathsea library. On a system without TeX the file can’t be rendered.

Specials#

\special{...} puts arbitrary bytes into the file with xxx commands. Drivers use them for everything TeX itself can’t do: color (color push rgb 1 0 0), included graphics (PSfile=fig.eps, pdf:image), hyperlinks, landscape pages, PostScript code (ps:). Specials are driver-specific: a DVI file made for dvips may lose graphics in dvipdfmx and the other way round. Included images stay external files.

XDV and other variants#

• XDV (.xdv, version byte 7, earlier 5 or 6): written by XeTeX; adds opcodes for OpenType/TrueType fonts referenced by file name and for positioned glyph arrays. xdvipdfmx converts it.
• pTeX/upTeX DVI (version byte 3 when vertical writing is used) adds a direction command for Japanese vertical text.

Converting DVI#

All converters come with TeX Live and MiKTeX:

dvipdfmx paper.dvi                    # to PDF (paper.pdf)
dvips paper.dvi -o paper.ps           # to PostScript
dvisvgm --no-fonts --page=1- paper.dvi   # each page to SVG, glyphs as paths
dvipng -D 300 -T tight formula.dvi    # each page to PNG at 300 dpi, cropped

dvitype (TeX Live) prints every command of a DVI file in readable form; dviasm turns DVI into an editable text form and back.

Specifications and documentation#

• The DVI Driver Standard, Level 0 (TUG DVI Driver Standards Committee, PDF): the file format and what a driver must do
• dvitype.web by Donald Knuth: the reference DVI reader, with the format described in its comments (texware on CTAN)
• dvipdfmx manual and dvips manual: the specials each driver supports
• Kpathsea: how drivers find TFM, PK and font files
• Device independent file format on Wikipedia

Software that opens DVI files#

Libraries#

Few libraries read DVI; most programs convert it with the TeX Live tools instead. See all DVI libraries.

Related formats#

• PDF: what DVI is normally converted to, with fonts and images embedded
• PostScript: the output of dvips
• EPS: the graphics format that latex + dvips includes
• SVG: dvisvgm output, for formulas and figures on the web