Finding out what characters a given font supports

Question

How do I extract the list of supported Unicode characters from a TrueType or embedded OpenType font on Linux?

Is there a tool or a library I can use to process a .ttf or a .eot file and build a list of code points (like U+0123, U+1234, etc.) provided by the font?

Answer 1

Here is a method using the FontTools module (which you can install with something like pip install fonttools):

#!/usr/bin/env python
from itertools import chain
import sys

from fontTools.ttLib import TTFont
from fontTools.unicode import Unicode

ttf = TTFont(sys.argv[1], 0, verbose=0, allowVID=0,
                ignoreDecompileErrors=True,
                fontNumber=-1)

chars = chain.from_iterable([y + (Unicode[y[0]],) for y in x.cmap.items()] for x in ttf["cmap"].tables)
print(list(chars))

# Use this for just checking if the font contains the codepoint given as
# second argument:
#char = int(sys.argv[2], 0)
#print(Unicode[char])
#print(char in (x[0] for x in chars))

ttf.close()

The script takes as argument the font path :

python checkfont.py /path/to/font.ttf

Answer 2

The Linux program xfd can do this. It's provided in my distro as 'xorg-xfd'. To see all characters for a font, you can run this in terminal:

xfd -fa "DejaVu Sans Mono"

Answer 3

fc-query my-font.ttf will give you a map of supported glyphs and all the locales the font is appropriate for according to fontconfig

Since pretty much all modern linux apps are fontconfig-based this is much more useful than a raw unicode list

The actual output format is discussed here http://lists.freedesktop.org/archives/fontconfig/2013-September/004915.html

Answer 4

The character code points for a ttf/otf font are stored in the CMAP table.

You can use ttx to generate a XML representation of the CMAP table. see here.

You can run the command ttx.exe -t cmap MyFont.ttf and it should output a file MyFont.ttx. Open it in a text editor and it should show you all the character code it found in the font.

Answer 5

The fontconfig commands can output the glyph list as a compact list of ranges, eg:

$ fc-match --format='%{charset}\n' OpenSans
20-7e a0-17f 192 1a0-1a1 1af-1b0 1f0 1fa-1ff 218-21b 237 2bc 2c6-2c7 2c9
2d8-2dd 2f3 300-301 303 309 30f 323 384-38a 38c 38e-3a1 3a3-3ce 3d1-3d2 3d6
400-486 488-513 1e00-1e01 1e3e-1e3f 1e80-1e85 1ea0-1ef9 1f4d 2000-200b
2013-2015 2017-201e 2020-2022 2026 2030 2032-2033 2039-203a 203c 2044 2070
2074-2079 207f 20a3-20a4 20a7 20ab-20ac 2105 2113 2116 2120 2122 2126 212e
215b-215e 2202 2206 220f 2211-2212 221a 221e 222b 2248 2260 2264-2265 25ca
fb00-fb04 feff fffc-fffd

Use fc-query for a .ttf file and fc-match for an installed font name.

This likely doesn't involve installing any extra packages, and doesn't involve translating a bitmap.

Use fc-match --format='%{file}\n' to check whether the right font is being matched.

Answer 6

I just had the same problem, and made a HOWTO that goes one step further, baking a regexp of all the supported Unicode code points.

If you just want the array of codepoints, you can use this when peeking at your ttx xml in Chrome devtools, after running ttx -t cmap myfont.ttf and, probably, renaming myfont.ttx to myfont.xml to invoke Chrome's xml mode:

function codepoint(node) { return Number(node.nodeValue); }
$x('//cmap/*[@platformID="0"]/*/@code').map(codepoint);

(Also relies on fonttools from gilamesh's suggestion; sudo apt-get install fonttools if you're on an ubuntu system.)

Answer 7

If you ONLY want to "view" the fonts, the following might be helpful (if your terminal supports the font in question):

#!/usr/bin/env python
import sys
from fontTools.ttLib import TTFont

with TTFont(sys.argv[1], 0, ignoreDecompileErrors=True) as ttf:
    for x in ttf["cmap"].tables:
        for (_, code) in x.cmap.items():
            point = code.replace('uni', '\\u').lower()
            print("echo -e '" + point + "'")

An unsafe, but easy way to view:

python font.py my-font.ttf | sh

Thanks to Janus (https://stackoverflow.com/a/19438403/431528) for the answer above.

Answer 8

The above Janus's answer (https://stackoverflow.com/a/19438403/431528) works. But python is too slow, especially for Asian fonts. It costs minutes for a 40MB file size font on my E5 computer.

So I write a little C++ program to do that. It is depends on FreeType2(https://www.freetype.org/). It is a vs2015 project, but it is easy to port to linux for it is a console application.

Code can be found here, https://github.com/zhk/AllCodePoints For the 40MB file size Asian font, it costs about 30 ms on my E5 computer.

Answer 9

If you want to get all characters supported by a font, you may use the following (based on Janus's answer)

from fontTools.ttLib import TTFont

def get_font_characters(font_path):
    with TTFont(font_path) as font:
        characters = {chr(y[0]) for x in font["cmap"].tables for y in x.cmap.items()}
    return characters

Answer 10

You can do this on Linux in Perl using the Font::TTF module.