pyftsubset --help
% pyftsubset --help
pyftsubset -- OpenType font subsetter and optimizer pyftsubset is an OpenType font subsetter and optimizer, based on fontTools. It accepts any TT- or CFF-flavored OpenType (.otf or .ttf) or WOFF (.woff) font file. The subsetted glyph set is based on the specified glyphs or characters, and specified OpenType layout features.
The tool also performs some size-reducing optimizations, aimed for using subset fonts as webfonts. Individual optimizations can be enabled or disabled, and are enabled by default when they are safe.
Usage: pyftsubset font-file [glyph...] [--option=value]... At least one glyph or one of --gids, --gids-file, --glyphs, --glyphs-file, --text, --text-file, --unicodes, or --unicodes-file, must be specified.
Arguments: font-file The input font file. glyph Specify one or more glyph identifiers to include in the subset. Must be PS glyph names, or the special string '*' to keep the entire glyph set.
Initial glyph set specification: These options populate the initial glyph set. Same option can appear multiple times, and the results are accummulated.
gid
--gids=<NNN>[,<NNN>...] Specify comma/whitespace-separated list of glyph IDs or ranges as decimal numbers. For example, --gids=10-12,14 adds glyphs with numbers 10, 11, 12, and 14. --gids-file=<path> Like --gids but reads from a file. Anything after a '#' on any line is ignored as comments.
glyphname
--glyphs=<glyphname>[,<glyphname>...] Specify comma/whitespace-separated PS glyph names to add to the subset. Note that only PS glyph names are accepted, not gidNNN, U+XXXX, etc that are accepted on the command line. The special string '*' will keep the entire glyph set. --glyphs-file=<path> Like --glyphs but reads from a file. Anything after a '#' on any line is ignored as comments.
Text
--text=<text> Specify characters to include in the subset, as UTF-8 string. --text-file=<path> Like --text but reads from a file. Newline character are not added to the subset.
Unicode
--unicodes=<XXXX>[,<XXXX>...] Specify comma/whitespace-separated list of Unicode codepoints or ranges as hex numbers, optionally prefixed with 'U+', 'u', etc. For example, --unicodes=41-5a,61-7a adds ASCII letters, so does the more verbose --unicodes=U+0041-005A,U+0061-007A. The special strings '*' will choose all Unicode characters mapped by the font. --unicodes-file=<path> Like --unicodes, but reads from a file. Anything after a '#' on any line in the file is ignored as comments.
--ignore-missing-glyphs Do not fail if some requested glyphs or gids are not available in the font. --no-ignore-missing-glyphs Stop and fail if some requested glyphs or gids are not available in the font. [default]
--ignore-missing-unicodes [default] Do not fail if some requested Unicode characters (including those indirectly specified using --text or --text-file) are not available in the font. --no-ignore-missing-unicodes Stop and fail if some requested Unicode characters are not available in the font. Note the default discrepancy between ignoring missing glyphs versus unicodes. ※This is for historical reasons and in the future --no-ignore-missing-unicodes might become default.
Other options:
For the other options listed below,
to see the current value of the option,
pass a value of '?' to it,
with or without a '='.
Examples:
$ pyftsubset --glyph-names?
Current setting for 'glyph-names' is: False
$ ./pyftsubset --name-IDs=?
Current setting for 'name-IDs' is: [0, 1, 2, 3, 4, 5, 6]
$ ./pyftsubset --hinting? --no-hinting --hinting?
Current setting for 'hinting' is: True
Current setting for 'hinting' is: False
Output options: --output-file=<path> The output font file. If not specified, the subsetted font will be saved in as font-file.subset. --flavor=<type> Specify flavor of output font file. May be 'woff' or 'woff2'. Note that WOFF2 requires the Brotli Python extension, available at https://github.com/google/brotli --with-zopfli Use the Google Zopfli algorithm to compress WOFF. The output is 3-8 % smaller than pure zlib, but the compression speed is much slower. The Zopfli Python bindings are available at: https://pypi.python.org/pypi/zopfli
Glyph set expansion:
These options control how additional glyphs
are added to the subset.
--retain-gids
Retain glyph indices; just empty glyphs not needed in-place.
--notdef-glyph
Add the '.notdef' glyph to the subset (ie, keep it). [default]
--no-notdef-glyph
Drop the '.notdef' glyph unless specified in the glyph set. This
saves a few bytes, but is not possible for Postscript-flavored
fonts, as those require '.notdef'. For TrueType-flavored fonts,
this works fine as long as no unsupported glyphs are requested
from the font.
--notdef-outline
Keep the outline of '.notdef' glyph. The '.notdef' glyph outline is
used when glyphs not supported by the font are to be shown. It is not
needed otherwise.
--no-notdef-outline
When including a '.notdef' glyph, remove its outline. This saves
a few bytes. [default]
--recommended-glyphs
Add glyphs 0, 1, 2, and 3 to the subset, as recommended for
TrueType-flavored fonts: '.notdef', 'NULL' or '.null', 'CR', 'space'.
Some legacy software might require this, but no modern system does.
--no-recommended-glyphs
Do not add glyphs 0, 1, 2, and 3 to the subset, unless specified in
glyph set. [default]
--no-layout-closure Do not expand glyph set to add glyphs produced by OpenType layout features. Instead, OpenType layout features will be subset to only rules that are relevant to the otherwise-specified glyph set. --layout-features[+|-]=<feature>[,<feature>...] Specify (=), add to (+=) or exclude from (-=) the comma-separated set of OpenType layout feature tags that will be preserved. Glyph variants used by the preserved features are added to the specified subset glyph set. By default, 'calt', 'ccmp', 'clig', 'curs', 'dnom', 'frac', 'kern', 'liga', 'locl', 'mark', 'mkmk', 'numr', 'rclt', 'rlig', 'rvrn', and all features required for script shaping are preserved. To see the full list, try '--layout-features=?'. Use '*' to keep all features. Multiple --layout-features options can be provided if necessary.
Examples:
--layout-features+=onum,pnum,ss01
* Keep the default set of features and 'onum', 'pnum', 'ss01'.
--layout-features-='mark','mkmk'
* Keep the default set of features but drop 'mark' and 'mkmk'.
--layout-features='kern'
* Only keep the 'kern' feature, drop all others.
--layout-features=''
* Drop all features.
--layout-features='*'
* Keep all features.
--layout-features+=aalt --layout-features-=vrt2
* Keep default set of features plus 'aalt', but drop 'vrt2'.
--layout-scripts[+|-]=<script>[,<script>...]
Specify (=),
add to (+=)
or exclude from (-=)
the comma-separated
set of OpenType layout script tags
that will be preserved.
By default all scripts are retained ('*').
Hinting options:
--hinting
Keep hinting [default]
--no-hinting
Drop glyph-specific hinting and font-wide hinting tables, as well
as remove hinting-related bits and pieces from other tables (eg. GPOS).
See --hinting-tables for list of tables that are dropped by default.
Instructions and hints are stripped from 'glyf' and 'CFF ' tables
respectively. This produces (sometimes up to 30%) smaller fonts that
are suitable for extremely high-resolution systems, like high-end
mobile devices and retina displays.
Optimization options: --desubroutinize Remove CFF use of subroutinizes. Subroutinization is a way to make CFF fonts smaller. For small subsets however, desubroutinizing might make the font smaller. It has even been reported that desubroutinized CFF fonts compress better (produce smaller output) WOFF and WOFF2 fonts. Also see note under --no-hinting. --no-desubroutinize [default] Leave CFF subroutinizes as is, only throw away unused subroutinizes.
Font table options: --drop-tables[+|-]=<table>[,<table>...] Specify (=), add to (+=) or exclude from (-=) the comma-separated set of tables that will be be dropped. By default, the following tables are dropped: 'BASE', 'JSTF', 'DSIG', 'EBDT', 'EBLC', 'EBSC', 'SVG ', 'PCLT', 'LTSH' and Graphite tables: 'Feat', 'Glat', 'Gloc', 'Silf', 'Sill'. The tool will attempt to subset the remaining tables.
Examples:
Examples: --drop-tables-='SVG ' * Drop the default set of tables but keep 'SVG '. --drop-tables+=GSUB * Drop the default set of tables and 'GSUB'. --drop-tables=DSIG * Only drop the 'DSIG' table, keep all others. --drop-tables= * Keep all tables.
--no-subset-tables+=<table>[,<table>...] Add to the set of tables that will not be subsetted. By default, the following tables are included in this list, as they do not need subsetting (ignore the fact that 'loca' is listed here): 'gasp', 'head', 'hhea', 'maxp', 'vhea', 'OS/2', 'loca', 'name', 'cvt ', 'fpgm', 'prep', 'VMDX', 'DSIG', 'CPAL', 'MVAR', 'cvar', 'STAT'. By default, tables that the tool does not know how to subset and are not specified here will be dropped from the font, unless --passthrough-tables option is passed.
Example: --no-subset-tables+=FFTM * Keep 'FFTM' table in the font by preventing subsetting. --passthrough-tables Do not drop tables that the tool does not know how to subset. --no-passthrough-tables Tables that the tool does not know how to subset and are not specified in --no-subset-tables will be dropped from the font. [default] --hinting-tables[-]=<table>[,<table>...] Specify (=), add to (+=) or exclude from (-=) the list of font-wide hinting tables that will be dropped if --no-hinting is specified, Examples: --hinting-tables-='VDMX' * Drop font-wide hinting tables except 'VDMX'. --hinting-tables='' * Keep all font-wide hinting tables (but strip hints from glyphs). --legacy-kern Keep TrueType 'kern' table even when OpenType 'GPOS' is available. --no-legacy-kern Drop TrueType 'kern' table if OpenType 'GPOS' is available. [default]
Font naming options:
Font naming options: These options control what is retained in the 'name' table. For numerical codes, see: http://www.microsoft.com/typography/otspec/name.htm --name-IDs[+|-]=<nameID>[,<nameID>...] Specify (=), add to (+=) or exclude from (-=) the set of 'name' table entry nameIDs that will be preserved. By default, only nameIDs between 0 and 6 are preserved, the rest are dropped. Use '*' to keep all entries.
Examples: --name-IDs+=7,8,9 * Also keep Trademark, Manufacturer and Designer name entries. --name-IDs='' * Drop all 'name' table entries. --name-IDs='*' * keep all 'name' table entries --name-legacy Keep legacy (non-Unicode) 'name' table entries (0.x, 1.x etc.). XXX Note: This might be needed for some fonts that have no Unicode name entires for English. See: https://github.com/fonttools/fonttools/issues/146 --no-name-legacy Drop legacy (non-Unicode) 'name' table entries [default] --name-languages[+|-]=<langID>[,<langID>] Specify (=), add to (+=) or exclude from (-=) the set of 'name' table langIDs that will be preserved. By default only records with langID 0x0409 (English) are preserved. Use '*' to keep all langIDs. --obfuscate-names Make the font unusable as a system font by replacing name IDs 1, 2, 3, 4, and 6 with dummy strings (it is still fully functional as webfont).
Glyph naming and encoding options:
Glyph naming and encoding options: --glyph-names Keep PS glyph names in TT-flavored fonts. In general glyph names are not needed for correct use of the font. However, some PDF generators and PDF viewers might rely on glyph names to extract Unicode text from PDF documents. --no-glyph-names Drop PS glyph names in TT-flavored fonts, by using 'post' table version 3.0. [default]
--legacy-cmap Keep the legacy 'cmap' subtables (0.x, 1.x, 4.x etc.). --no-legacy-cmap Drop the legacy 'cmap' subtables. [default] --symbol-cmap Keep the 3.0 symbol 'cmap'. --no-symbol-cmap Drop the 3.0 symbol 'cmap'. [default]
Other font-specific options:
Other font-specific options: --recalc-bounds Recalculate font bounding boxes. --no-recalc-bounds Keep original font bounding boxes. This is faster and still safe for all practical purposes. [default]
--recalc-timestamp Set font 'modified' timestamp to current time. --no-recalc-timestamp Do not modify font 'modified' timestamp. [default]
--canonical-order Order tables as recommended in the OpenType standard. This is not required by the standard, nor by any known implementation. --no-canonical-order Keep original order of font tables. This is faster. [default]
--prune-unicode-ranges Update the 'OS/2 ulUnicodeRange*' bits after subsetting. The Unicode ranges defined in the OpenType specification v1.7 are intersected with the Unicode codepoints specified in the font's Unicode 'cmap' subtables: when no overlap is found, the bit will be switched off. However, it will *not* be switched on if an intersection is found. [default] --no-prune-unicode-ranges Don't change the 'OS/2 ulUnicodeRange*' bits.
--recalc-average-width Update the 'OS/2 xAvgCharWidth' field after subsetting. --no-recalc-average-width Don't change the 'OS/2 xAvgCharWidth' field. [default]
--recalc-max-context Update the 'OS/2 usMaxContext' field after subsetting. --no-recalc-max-context Don't change the 'OS/2 usMaxContext' field. [default]
--font-number=<number> Select font number for TrueType Collection (.ttc/.otc), starting from 0.
Application options:
--verbose
Display verbose information of the subsetting process.
--timing
Display detailed timing information of the subsetting process.
--xml
Display the TTX XML representation of subsetted font.
Example: Produce a subset containing the characters ' !"#$%' without performing size-reducing optimizations: $ pyftsubset font.ttf --unicodes="U+0020-0025" \ --layout-features='*' --glyph-names --symbol-cmap --legacy-cmap \ --notdef-glyph --notdef-outline --recommended-glyphs \ --name-IDs='*' --name-legacy --name-languages='*'
