Digitype

User guide

Digitype turns scans of typewriter type samples into clean, installable fonts. You show it where each character is on the scans; it averages every impression of each character, cleans it up and writes two fixed-pitch TrueType fonts.

• Install and start
• Projects, pages and font sets
• Labelling
• Baselines
• Warnings and checks
• Regenerate
• Results and test type
• The fonts
• Tips for good results
• Controls

See also: Preparing type samples · How it works · Settings reference

Install and start

You need Python 3.10 or newer.

Windows: run run.bat with your samples, from a terminal in the repository folder:

run.bat "D:\Scans\Type Samples"

The first run creates a .venv and installs the requirements; after that it starts at once.

Anywhere:

python3 -m venv .venv
.venv/bin/pip install -r requirements.txt
.venv/bin/python3 -m digitype label "path/to/samples" [more files or folders] [--project DIR]

It opens http://127.0.0.1:8770 in your browser. Options: --port, --host (use 0.0.0.0 to reach it from another computer on your network), --no-browser.

Everything stays on your computer: the page talks only to the local server.

Projects, pages and font sets

A project is a folder (by default projects/<name of the first source>) that holds your labels, settings, a cache of the pages, and everything Regenerate writes. Projects are not part of git.

Pages. Every image file is a page, every frame of a multi-page TIFF is a page, and every page of a PDF is a page (rendered at 600 dpi). Add more at any time:

• Upload PDF / images… (top of the Pages list) copies files from your browser into the project’s uploads/ folder.
• Add from a path… adds a file or folder already on the computer running Digitype.

Big scans are fine: each page is converted to grey once and cached, so later visits are quick.

This page (under the page list) has per-page tools:

• DPI. Files often carry a wrong resolution or none. Set the real one here if you know it. It is only used to turn the pitch setting into pixels; glyph sizes come from the cells themselves.
• Rotate. Straighten a crooked scan: drag the slider and the page turns live under fixed guide lines; line a row of text up with them and let go. Type an exact angle in the box (clockwise +, up to 45°), 0° resets, and ⟲ 90° / ⟳ 90° turn the page a quarter turn. Boxes already on the page turn with it (a hand-set baseline goes back to automatic).
• Guides shows the guide lines at any time; the red one follows the pointer.

Font sets. One project can hold several typefaces, for example a sample book with a different face on every page. Each typeface is its own font set, chosen in the top bar:

• + New font starts a new, empty set (its settings start as a copy of the current set’s).
• Rename, and Delete (only for a set with no boxes, so nothing is lost by accident).
• Boxes, pitch, font name and every other setting are kept per set.
• Regenerate only uses the set you’re on, so two typefaces are never averaged together.
• Other sets’ boxes show dimmed and dashed on the page, and can’t be clicked.
• A selected box can be moved to another set with the Font picker in the side panel.

Labelling

Draw a box around a character and type it, then press Enter.

Type a whole line. Draw one box around a run of text and type exactly what it says, spaces included. The box becomes one cell per character, and each cell’s character is drawn under it so you can check the fit at a glance. This is the fast way to label body text, which gives you many samples of every common letter.

• The glyphs along the line are found first, and your text is matched to them in order, so each letter’s cell sits on its own glyph, even in rows whose spacing changes along the line (charts set or pasted together rather than typed in one go).
• Where glyphs can’t be told apart (letters running together), the line is split on an even grid, its pitch measured from the row’s own rhythm.
• Where the ink shows a gap your text doesn’t have (or the other way round), the spacing is adjusted to the ink and the box says so (“+1 space after …”), so you can fix the text.
• Type accented letters as they are on the page (Ä, ü, é…). A plain letter labelled where the page has an accented one adds the accent to the plain letter.

Editing boxes.

• Click a box to select it. Double-click (or Enter) edits its text.
• Drag one of the eight handles of the selected box to resize it.
• Shift+drag moves a box. Boxes are otherwise locked, so a click that wobbles never changes your data.
• Arrow keys nudge the selected box by a pixel (Shift: 10).
• Delete removes it.

The Glyphs panel lists every character labelled in the current set with its sample count; click one to visit its samples in turn.

Baselines

Every sample needs a baseline, the line the letters sit on.

• Letters that sit on the line (most letters, figures, . ! ? :) give it: the bottom of their ink.
• Letters that hang below or float above (g j p q y , ; ( ) _ ' "…) take it from the others on their line, or, in a single-glyph box, from boxes beside it on the page.
• Adaptive baselines (the default) are fitted locally along each line, so a skewed scan or a wavy line is followed. Straight fits one straight, possibly tilted, line per run.
• Tilt correction turns each sample level by its line’s tilt before averaging.
• Shift+drag the red baseline of a selected box to set it by hand; Auto baseline goes back.

The red lines on the page are drawn at their actual slope.

Warnings and checks

A box turns red and explains itself in the side panel when the text can’t match the ink:

• the number of characters doesn’t fit the box at the font’s pitch;
• the ink spans more or fewer cells than the text has characters;
• spaces land on ink, or letters on blank paper (usually a missing or extra space; the warning shows where it starts).

During Regenerate, a sample that clearly disagrees with the other samples of its character (often a label mistake, such as an ä labelled a, or a letter one cell off) is left out of the average. It is listed in the log, on the glyph’s card (“1 odd left out”), and in the enlarged view with a button to jump to its box.

Regenerate

Regenerate builds the current font set. The log shows each character as it goes. For each character, every sample is cut out, scaled to a common size, lined up with the others, averaged, traced, and also reduced to a seed and grown back. Details: How it works.

Output goes to projects/<name>/out/<NN set name>/:

File	What it is
<name>-Average.ttf	The averaged samples, traced: the most faithful version
<name>-Seed.ttf	Each glyph reduced to its skeleton (seed) and grown back
seeds/seed_XXXX.json	The seed of each character: strokes, half-widths, nodes
result.json	What the Results page shows

Results and test type

The Results tab shows every character as three panels, all at one common scale with the baseline and cell drawn in:

1. averaged: the averaged scan,
2. traced: its outline (the Average font),
3. seed, regrown: the Seed font, with the seed’s strokes in orange (toggle seed strokes).

Each card shows the sample count and match, how closely the seed and the trace agree. Sort by character, most or fewest samples, or worst match first (a quick way to find what needs more samples or a label fix). Click a card to enlarge it.

Test type at the top sets any text you type in both fonts as soon as they’re written, with a size slider. Characters the font doesn’t have yet are listed underneath.

Glyph images (cleaned-up or drawn characters)

The Glyph images tab takes clean pictures of single characters: a glyph you cleaned up, or a character the samples don’t have at all, drawn by hand or made with an AI image tool. When you Regenerate, a picture is used instead of the scans for its character, in both fonts (the scans are kept, just not used; untick use to go back to them).

1. Add glyph images… (PNG, JPG, BMP, TIFF, WebP; dark on light, or on transparent).
2. Type which character each picture is. A file named after its character (&.png, uni0026.png, U+0026.png) is filled in for you.
3. It is placed automatically: onto the character’s own average when it has samples, otherwise where DejaVu Sans Mono puts that character, scaled to this face’s cap height (Regenerate once first so the face’s size is known). Drag to move, wheel to scale (Shift = fine), arrow keys nudge (Shift ×10); Auto place starts over. Compare with draws another character of the font faintly behind every picture, for size and weight.

To clean up a glyph you already have: enlarge it in Results and Save picture for clean-up. It saves an enlarged averaged scan named uniXXXX.png; clean it up and add the result back, and it is labelled and fitted onto its scans by itself.

The fonts

Both fonts are true monospaced fonts: every glyph is one cell wide (600 units on a 1000-unit em), and they are flagged fixed-pitch (post.isFixedPitch and PANOSE bProportion = 9), so font menus list them as monospaced. They carry the full set of names Windows needs and install normally.

The family name is the font set’s Font name setting, or the set’s name.

Tips for good results

• Making a new sample? Follow Preparing type samples: 1.5 or double line spacing, a space between characters, every character several times, a greyscale scan.

• Label lots of body text. More samples of a letter means a cleaner, more faithful average. Single samples work, and are smoothed to look consistent, but more is always better.
• One typeface per font set. Different faces averaged together produce mush.
• Set the pitch. After labelling a couple of lines, the Settings panel suggests the pitch it measured; click Use to take it.
• Type accents. An ä labelled a puts dots on your a.
• Boxes can be loose vertically. Samples are captured well above and below the baseline whatever the box size, and marks from neighbouring lines are kept out.
• Look at “worst match first” in Results to see which glyphs need attention.

Controls

Action	How
Zoom	Mouse wheel (the full-resolution scan loads as you zoom in)
Pan	Right-drag, middle-drag, or Space + drag
Fit the page	F
New box	Drag on empty page, type its text, Enter (Esc cancels)
Select	Click a box
Edit text	Double-click, or Enter
Resize	Drag a handle of the selected box
Move	Shift + drag the box
Set baseline	Shift + drag the red line
Nudge	Arrow keys (Shift: ×10)
Delete	Delete or Backspace