from io import BytesIO import sys import array import struct from collections import OrderedDict from fontTools.misc import sstruct from fontTools.misc.arrayTools import calcIntBounds from fontTools.misc.textTools import Tag, bytechr, byteord, bytesjoin, pad from fontTools.ttLib import ( TTFont, TTLibError, getTableModule, getTableClass, getSearchRange, ) from fontTools.ttLib.sfnt import ( SFNTReader, SFNTWriter, DirectoryEntry, WOFFFlavorData, sfntDirectoryFormat, sfntDirectorySize, SFNTDirectoryEntry, sfntDirectoryEntrySize, calcChecksum, ) from fontTools.ttLib.tables import ttProgram, _g_l_y_f import logging log = logging.getLogger("fontTools.ttLib.woff2") haveBrotli = False try: try: import brotlicffi as brotli except ImportError: import brotli haveBrotli = True except ImportError: pass class WOFF2Reader(SFNTReader): flavor = "woff2" def __init__(self, file, checkChecksums=0, fontNumber=-1): if not haveBrotli: log.error( "The WOFF2 decoder requires the Brotli Python extension, available at: " "https://github.com/google/brotli" ) raise ImportError("No module named brotli") self.file = file signature = Tag(self.file.read(4)) if signature != b"wOF2": raise TTLibError("Not a WOFF2 font (bad signature)") self.file.seek(0) self.DirectoryEntry = WOFF2DirectoryEntry data = self.file.read(woff2DirectorySize) if len(data) != woff2DirectorySize: raise TTLibError("Not a WOFF2 font (not enough data)") sstruct.unpack(woff2DirectoryFormat, data, self) self.tables = OrderedDict() offset = 0 for i in range(self.numTables): entry = self.DirectoryEntry() entry.fromFile(self.file) tag = Tag(entry.tag) self.tables[tag] = entry entry.offset = offset offset += entry.length totalUncompressedSize = offset compressedData = self.file.read(self.totalCompressedSize) decompressedData = brotli.decompress(compressedData) if len(decompressedData) != totalUncompressedSize: raise TTLibError( "unexpected size for decompressed font data: expected %d, found %d" % (totalUncompressedSize, len(decompressedData)) ) self.transformBuffer = BytesIO(decompressedData) self.file.seek(0, 2) if self.length != self.file.tell(): raise TTLibError("reported 'length' doesn't match the actual file size") self.flavorData = WOFF2FlavorData(self) # make empty TTFont to store data while reconstructing tables self.ttFont = TTFont(recalcBBoxes=False, recalcTimestamp=False) def __getitem__(self, tag): """Fetch the raw table data. Reconstruct transformed tables.""" entry = self.tables[Tag(tag)] if not hasattr(entry, "data"): if entry.transformed: entry.data = self.reconstructTable(tag) else: entry.data = entry.loadData(self.transformBuffer) return entry.data def reconstructTable(self, tag): """Reconstruct table named 'tag' from transformed data.""" entry = self.tables[Tag(tag)] rawData = entry.loadData(self.transformBuffer) if tag == "glyf": # no need to pad glyph data when reconstructing padding = self.padding if hasattr(self, "padding") else None data = self._reconstructGlyf(rawData, padding) elif tag == "loca": data = self._reconstructLoca() elif tag == "hmtx": data = self._reconstructHmtx(rawData) else: raise TTLibError("transform for table '%s' is unknown" % tag) return data def _reconstructGlyf(self, data, padding=None): """Return recostructed glyf table data, and set the corresponding loca's locations. Optionally pad glyph offsets to the specified number of bytes. """ self.ttFont["loca"] = WOFF2LocaTable() glyfTable = self.ttFont["glyf"] = WOFF2GlyfTable() glyfTable.reconstruct(data, self.ttFont) if padding: glyfTable.padding = padding data = glyfTable.compile(self.ttFont) return data def _reconstructLoca(self): """Return reconstructed loca table data.""" if "loca" not in self.ttFont: # make sure glyf is reconstructed first self.tables["glyf"].data = self.reconstructTable("glyf") locaTable = self.ttFont["loca"] data = locaTable.compile(self.ttFont) if len(data) != self.tables["loca"].origLength: raise TTLibError( "reconstructed 'loca' table doesn't match original size: " "expected %d, found %d" % (self.tables["loca"].origLength, len(data)) ) return data def _reconstructHmtx(self, data): """Return reconstructed hmtx table data.""" # Before reconstructing 'hmtx' table we need to parse other tables: # 'glyf' is required for reconstructing the sidebearings from the glyphs' # bounding box; 'hhea' is needed for the numberOfHMetrics field. if "glyf" in self.flavorData.transformedTables: # transformed 'glyf' table is self-contained, thus 'loca' not needed tableDependencies = ("maxp", "hhea", "glyf") else: # decompiling untransformed 'glyf' requires 'loca', which requires 'head' tableDependencies = ("maxp", "head", "hhea", "loca", "glyf") for tag in tableDependencies: self._decompileTable(tag) hmtxTable = self.ttFont["hmtx"] = WOFF2HmtxTable() hmtxTable.reconstruct(data, self.ttFont) data = hmtxTable.compile(self.ttFont) return data def _decompileTable(self, tag): """Decompile table data and store it inside self.ttFont.""" data = self[tag] if self.ttFont.isLoaded(tag): return self.ttFont[tag] tableClass = getTableClass(tag) table = tableClass(tag) self.ttFont.tables[tag] = table table.decompile(data, self.ttFont) class WOFF2Writer(SFNTWriter): flavor = "woff2" def __init__( self, file, numTables, sfntVersion="\000\001\000\000", flavor=None, flavorData=None, ): if not haveBrotli: log.error( "The WOFF2 encoder requires the Brotli Python extension, available at: " "https://github.com/google/brotli" ) raise ImportError("No module named brotli") self.file = file self.numTables = numTables self.sfntVersion = Tag(sfntVersion) self.flavorData = WOFF2FlavorData(data=flavorData) self.directoryFormat = woff2DirectoryFormat self.directorySize = woff2DirectorySize self.DirectoryEntry = WOFF2DirectoryEntry self.signature = Tag("wOF2") self.nextTableOffset = 0 self.transformBuffer = BytesIO() self.tables = OrderedDict() # make empty TTFont to store data while normalising and transforming tables self.ttFont = TTFont(recalcBBoxes=False, recalcTimestamp=False) def __setitem__(self, tag, data): """Associate new entry named 'tag' with raw table data.""" if tag in self.tables: raise TTLibError("cannot rewrite '%s' table" % tag) if tag == "DSIG": # always drop DSIG table, since the encoding process can invalidate it self.numTables -= 1 return entry = self.DirectoryEntry() entry.tag = Tag(tag) entry.flags = getKnownTagIndex(entry.tag) # WOFF2 table data are written to disk only on close(), after all tags # have been specified entry.data = data self.tables[tag] = entry def close(self): """All tags must have been specified. Now write the table data and directory.""" if len(self.tables) != self.numTables: raise TTLibError( "wrong number of tables; expected %d, found %d" % (self.numTables, len(self.tables)) ) if self.sfntVersion in ("\x00\x01\x00\x00", "true"): isTrueType = True elif self.sfntVersion == "OTTO": isTrueType = False else: raise TTLibError("Not a TrueType or OpenType font (bad sfntVersion)") # The WOFF2 spec no longer requires the glyph offsets to be 4-byte aligned. # However, the reference WOFF2 implementation still fails to reconstruct # 'unpadded' glyf tables, therefore we need to 'normalise' them. # See: # https://github.com/khaledhosny/ots/issues/60 # https://github.com/google/woff2/issues/15 if ( isTrueType and "glyf" in self.flavorData.transformedTables and "glyf" in self.tables ): self._normaliseGlyfAndLoca(padding=4) self._setHeadTransformFlag() # To pass the legacy OpenType Sanitiser currently included in browsers, # we must sort the table directory and data alphabetically by tag. # See: # https://github.com/google/woff2/pull/3 # https://lists.w3.org/Archives/Public/public-webfonts-wg/2015Mar/0000.html # # 2023: We rely on this in _transformTables where we expect that # "loca" comes after "glyf" table. self.tables = OrderedDict(sorted(self.tables.items())) self.totalSfntSize = self._calcSFNTChecksumsLengthsAndOffsets() fontData = self._transformTables() compressedFont = brotli.compress(fontData, mode=brotli.MODE_FONT) self.totalCompressedSize = len(compressedFont) self.length = self._calcTotalSize() self.majorVersion, self.minorVersion = self._getVersion() self.reserved = 0 directory = self._packTableDirectory() self.file.seek(0) self.file.write(pad(directory + compressedFont, size=4)) self._writeFlavorData() def _normaliseGlyfAndLoca(self, padding=4): """Recompile glyf and loca tables, aligning glyph offsets to multiples of 'padding' size. Update the head table's 'indexToLocFormat' accordingly while compiling loca. """ if self.sfntVersion == "OTTO": return for tag in ("maxp", "head", "loca", "glyf", "fvar"): if tag in self.tables: self._decompileTable(tag) self.ttFont["glyf"].padding = padding for tag in ("glyf", "loca"): self._compileTable(tag) def _setHeadTransformFlag(self): """Set bit 11 of 'head' table flags to indicate that the font has undergone a lossless modifying transform. Re-compile head table data.""" self._decompileTable("head") self.ttFont["head"].flags |= 1 << 11 self._compileTable("head") def _decompileTable(self, tag): """Fetch table data, decompile it, and store it inside self.ttFont.""" tag = Tag(tag) if tag not in self.tables: raise TTLibError("missing required table: %s" % tag) if self.ttFont.isLoaded(tag): return data = self.tables[tag].data if tag == "loca": tableClass = WOFF2LocaTable elif tag == "glyf": tableClass = WOFF2GlyfTable elif tag == "hmtx": tableClass = WOFF2HmtxTable else: tableClass = getTableClass(tag) table = tableClass(tag) self.ttFont.tables[tag] = table table.decompile(data, self.ttFont) def _compileTable(self, tag): """Compile table and store it in its 'data' attribute.""" self.tables[tag].data = self.ttFont[tag].compile(self.ttFont) def _calcSFNTChecksumsLengthsAndOffsets(self): """Compute the 'original' SFNT checksums, lengths and offsets for checksum adjustment calculation. Return the total size of the uncompressed font. """ offset = sfntDirectorySize + sfntDirectoryEntrySize * len(self.tables) for tag, entry in self.tables.items(): data = entry.data entry.origOffset = offset entry.origLength = len(data) if tag == "head": entry.checkSum = calcChecksum(data[:8] + b"\0\0\0\0" + data[12:]) else: entry.checkSum = calcChecksum(data) offset += (entry.origLength + 3) & ~3 return offset def _transformTables(self): """Return transformed font data.""" transformedTables = self.flavorData.transformedTables for tag, entry in self.tables.items(): data = None if tag in transformedTables: data = self.transformTable(tag) if data is not None: entry.transformed = True if data is None: if tag == "glyf": # Currently we always sort table tags so # 'loca' comes after 'glyf'. transformedTables.discard("loca") # pass-through the table data without transformation data = entry.data entry.transformed = False entry.offset = self.nextTableOffset entry.saveData(self.transformBuffer, data) self.nextTableOffset += entry.length self.writeMasterChecksum() fontData = self.transformBuffer.getvalue() return fontData def transformTable(self, tag): """Return transformed table data, or None if some pre-conditions aren't met -- in which case, the non-transformed table data will be used. """ if tag == "loca": data = b"" elif tag == "glyf": for tag in ("maxp", "head", "loca", "glyf"): self._decompileTable(tag) glyfTable = self.ttFont["glyf"] data = glyfTable.transform(self.ttFont) elif tag == "hmtx": if "glyf" not in self.tables: return for tag in ("maxp", "head", "hhea", "loca", "glyf", "hmtx"): self._decompileTable(tag) hmtxTable = self.ttFont["hmtx"] data = hmtxTable.transform(self.ttFont) # can be None else: raise TTLibError("Transform for table '%s' is unknown" % tag) return data def _calcMasterChecksum(self): """Calculate checkSumAdjustment.""" tags = list(self.tables.keys()) checksums = [] for i in range(len(tags)): checksums.append(self.tables[tags[i]].checkSum) # Create a SFNT directory for checksum calculation purposes self.searchRange, self.entrySelector, self.rangeShift = getSearchRange( self.numTables, 16 ) directory = sstruct.pack(sfntDirectoryFormat, self) tables = sorted(self.tables.items()) for tag, entry in tables: sfntEntry = SFNTDirectoryEntry() sfntEntry.tag = entry.tag sfntEntry.checkSum = entry.checkSum sfntEntry.offset = entry.origOffset sfntEntry.length = entry.origLength directory = directory + sfntEntry.toString() directory_end = sfntDirectorySize + len(self.tables) * sfntDirectoryEntrySize assert directory_end == len(directory) checksums.append(calcChecksum(directory)) checksum = sum(checksums) & 0xFFFFFFFF # BiboAfba! checksumadjustment = (0xB1B0AFBA - checksum) & 0xFFFFFFFF return checksumadjustment def writeMasterChecksum(self): """Write checkSumAdjustment to the transformBuffer.""" checksumadjustment = self._calcMasterChecksum() self.transformBuffer.seek(self.tables["head"].offset + 8) self.transformBuffer.write(struct.pack(">L", checksumadjustment)) def _calcTotalSize(self): """Calculate total size of WOFF2 font, including any meta- and/or private data.""" offset = self.directorySize for entry in self.tables.values(): offset += len(entry.toString()) offset += self.totalCompressedSize offset = (offset + 3) & ~3 offset = self._calcFlavorDataOffsetsAndSize(offset) return offset def _calcFlavorDataOffsetsAndSize(self, start): """Calculate offsets and lengths for any meta- and/or private data.""" offset = start data = self.flavorData if data.metaData: self.metaOrigLength = len(data.metaData) self.metaOffset = offset self.compressedMetaData = brotli.compress( data.metaData, mode=brotli.MODE_TEXT ) self.metaLength = len(self.compressedMetaData) offset += self.metaLength else: self.metaOffset = self.metaLength = self.metaOrigLength = 0 self.compressedMetaData = b"" if data.privData: # make sure private data is padded to 4-byte boundary offset = (offset + 3) & ~3 self.privOffset = offset self.privLength = len(data.privData) offset += self.privLength else: self.privOffset = self.privLength = 0 return offset def _getVersion(self): """Return the WOFF2 font's (majorVersion, minorVersion) tuple.""" data = self.flavorData if data.majorVersion is not None and data.minorVersion is not None: return data.majorVersion, data.minorVersion else: # if None, return 'fontRevision' from 'head' table if "head" in self.tables: return struct.unpack(">HH", self.tables["head"].data[4:8]) else: return 0, 0 def _packTableDirectory(self): """Return WOFF2 table directory data.""" directory = sstruct.pack(self.directoryFormat, self) for entry in self.tables.values(): directory = directory + entry.toString() return directory def _writeFlavorData(self): """Write metadata and/or private data using appropiate padding.""" compressedMetaData = self.compressedMetaData privData = self.flavorData.privData if compressedMetaData and privData: compressedMetaData = pad(compressedMetaData, size=4) if compressedMetaData: self.file.seek(self.metaOffset) assert self.file.tell() == self.metaOffset self.file.write(compressedMetaData) if privData: self.file.seek(self.privOffset) assert self.file.tell() == self.privOffset self.file.write(privData) def reordersTables(self): return True # -- woff2 directory helpers and cruft woff2DirectoryFormat = """ > # big endian signature: 4s # "wOF2" sfntVersion: 4s length: L # total woff2 file size numTables: H # number of tables reserved: H # set to 0 totalSfntSize: L # uncompressed size totalCompressedSize: L # compressed size majorVersion: H # major version of WOFF file minorVersion: H # minor version of WOFF file metaOffset: L # offset to metadata block metaLength: L # length of compressed metadata metaOrigLength: L # length of uncompressed metadata privOffset: L # offset to private data block privLength: L # length of private data block """ woff2DirectorySize = sstruct.calcsize(woff2DirectoryFormat) woff2KnownTags = ( "cmap", "head", "hhea", "hmtx", "maxp", "name", "OS/2", "post", "cvt ", "fpgm", "glyf", "loca", "prep", "CFF ", "VORG", "EBDT", "EBLC", "gasp", "hdmx", "kern", "LTSH", "PCLT", "VDMX", "vhea", "vmtx", "BASE", "GDEF", "GPOS", "GSUB", "EBSC", "JSTF", "MATH", "CBDT", "CBLC", "COLR", "CPAL", "SVG ", "sbix", "acnt", "avar", "bdat", "bloc", "bsln", "cvar", "fdsc", "feat", "fmtx", "fvar", "gvar", "hsty", "just", "lcar", "mort", "morx", "opbd", "prop", "trak", "Zapf", "Silf", "Glat", "Gloc", "Feat", "Sill", ) woff2FlagsFormat = """ > # big endian flags: B # table type and flags """ woff2FlagsSize = sstruct.calcsize(woff2FlagsFormat) woff2UnknownTagFormat = """ > # big endian tag: 4s # 4-byte tag (optional) """ woff2UnknownTagSize = sstruct.calcsize(woff2UnknownTagFormat) woff2UnknownTagIndex = 0x3F woff2Base128MaxSize = 5 woff2DirectoryEntryMaxSize = ( woff2FlagsSize + woff2UnknownTagSize + 2 * woff2Base128MaxSize ) woff2TransformedTableTags = ("glyf", "loca") woff2GlyfTableFormat = """ > # big endian version: H # = 0x0000 optionFlags: H # Bit 0: we have overlapSimpleBitmap[], Bits 1-15: reserved numGlyphs: H # Number of glyphs indexFormat: H # Offset format for loca table nContourStreamSize: L # Size of nContour stream nPointsStreamSize: L # Size of nPoints stream flagStreamSize: L # Size of flag stream glyphStreamSize: L # Size of glyph stream compositeStreamSize: L # Size of composite stream bboxStreamSize: L # Comnined size of bboxBitmap and bboxStream instructionStreamSize: L # Size of instruction stream """ woff2GlyfTableFormatSize = sstruct.calcsize(woff2GlyfTableFormat) bboxFormat = """ > # big endian xMin: h yMin: h xMax: h yMax: h """ woff2OverlapSimpleBitmapFlag = 0x0001 def getKnownTagIndex(tag): """Return index of 'tag' in woff2KnownTags list. Return 63 if not found.""" for i in range(len(woff2KnownTags)): if tag == woff2KnownTags[i]: return i return woff2UnknownTagIndex class WOFF2DirectoryEntry(DirectoryEntry): def fromFile(self, file): pos = file.tell() data = file.read(woff2DirectoryEntryMaxSize) left = self.fromString(data) consumed = len(data) - len(left) file.seek(pos + consumed) def fromString(self, data): if len(data) < 1: raise TTLibError("can't read table 'flags': not enough data") dummy, data = sstruct.unpack2(woff2FlagsFormat, data, self) if self.flags & 0x3F == 0x3F: # if bits [0..5] of the flags byte == 63, read a 4-byte arbitrary tag value if len(data) < woff2UnknownTagSize: raise TTLibError("can't read table 'tag': not enough data") dummy, data = sstruct.unpack2(woff2UnknownTagFormat, data, self) else: # otherwise, tag is derived from a fixed 'Known Tags' table self.tag = woff2KnownTags[self.flags & 0x3F] self.tag = Tag(self.tag) self.origLength, data = unpackBase128(data) self.length = self.origLength if self.transformed: self.length, data = unpackBase128(data) if self.tag == "loca" and self.length != 0: raise TTLibError("the transformLength of the 'loca' table must be 0") # return left over data return data def toString(self): data = bytechr(self.flags) if (self.flags & 0x3F) == 0x3F: data += struct.pack(">4s", self.tag.tobytes()) data += packBase128(self.origLength) if self.transformed: data += packBase128(self.length) return data @property def transformVersion(self): """Return bits 6-7 of table entry's flags, which indicate the preprocessing transformation version number (between 0 and 3). """ return self.flags >> 6 @transformVersion.setter def transformVersion(self, value): assert 0 <= value <= 3 self.flags |= value << 6 @property def transformed(self): """Return True if the table has any transformation, else return False.""" # For all tables in a font, except for 'glyf' and 'loca', the transformation # version 0 indicates the null transform (where the original table data is # passed directly to the Brotli compressor). For 'glyf' and 'loca' tables, # transformation version 3 indicates the null transform if self.tag in {"glyf", "loca"}: return self.transformVersion != 3 else: return self.transformVersion != 0 @transformed.setter def transformed(self, booleanValue): # here we assume that a non-null transform means version 0 for 'glyf' and # 'loca' and 1 for every other table (e.g. hmtx); but that may change as # new transformation formats are introduced in the future (if ever). if self.tag in {"glyf", "loca"}: self.transformVersion = 3 if not booleanValue else 0 else: self.transformVersion = int(booleanValue) class WOFF2LocaTable(getTableClass("loca")): """Same as parent class. The only difference is that it attempts to preserve the 'indexFormat' as encoded in the WOFF2 glyf table. """ def __init__(self, tag=None): self.tableTag = Tag(tag or "loca") def compile(self, ttFont): try: max_location = max(self.locations) except AttributeError: self.set([]) max_location = 0 if "glyf" in ttFont and hasattr(ttFont["glyf"], "indexFormat"): # copile loca using the indexFormat specified in the WOFF2 glyf table indexFormat = ttFont["glyf"].indexFormat if indexFormat == 0: if max_location >= 0x20000: raise TTLibError("indexFormat is 0 but local offsets > 0x20000") if not all(l % 2 == 0 for l in self.locations): raise TTLibError( "indexFormat is 0 but local offsets not multiples of 2" ) locations = array.array("H") for i in range(len(self.locations)): locations.append(self.locations[i] // 2) else: locations = array.array("I", self.locations) if sys.byteorder != "big": locations.byteswap() data = locations.tobytes() else: # use the most compact indexFormat given the current glyph offsets data = super(WOFF2LocaTable, self).compile(ttFont) return data class WOFF2GlyfTable(getTableClass("glyf")): """Decoder/Encoder for WOFF2 'glyf' table transform.""" subStreams = ( "nContourStream", "nPointsStream", "flagStream", "glyphStream", "compositeStream", "bboxStream", "instructionStream", ) def __init__(self, tag=None): self.tableTag = Tag(tag or "glyf") def reconstruct(self, data, ttFont): """Decompile transformed 'glyf' data.""" inputDataSize = len(data) if inputDataSize < woff2GlyfTableFormatSize: raise TTLibError("not enough 'glyf' data") dummy, data = sstruct.unpack2(woff2GlyfTableFormat, data, self) offset = woff2GlyfTableFormatSize for stream in self.subStreams: size = getattr(self, stream + "Size") setattr(self, stream, data[:size]) data = data[size:] offset += size hasOverlapSimpleBitmap = self.optionFlags & woff2OverlapSimpleBitmapFlag self.overlapSimpleBitmap = None if hasOverlapSimpleBitmap: overlapSimpleBitmapSize = (self.numGlyphs + 7) >> 3 self.overlapSimpleBitmap = array.array("B", data[:overlapSimpleBitmapSize]) offset += overlapSimpleBitmapSize if offset != inputDataSize: raise TTLibError( "incorrect size of transformed 'glyf' table: expected %d, received %d bytes" % (offset, inputDataSize) ) bboxBitmapSize = ((self.numGlyphs + 31) >> 5) << 2 bboxBitmap = self.bboxStream[:bboxBitmapSize] self.bboxBitmap = array.array("B", bboxBitmap) self.bboxStream = self.bboxStream[bboxBitmapSize:] self.nContourStream = array.array("h", self.nContourStream) if sys.byteorder != "big": self.nContourStream.byteswap() assert len(self.nContourStream) == self.numGlyphs if "head" in ttFont: ttFont["head"].indexToLocFormat = self.indexFormat try: self.glyphOrder = ttFont.getGlyphOrder() except: self.glyphOrder = None if self.glyphOrder is None: self.glyphOrder = [".notdef"] self.glyphOrder.extend(["glyph%.5d" % i for i in range(1, self.numGlyphs)]) else: if len(self.glyphOrder) != self.numGlyphs: raise TTLibError( "incorrect glyphOrder: expected %d glyphs, found %d" % (len(self.glyphOrder), self.numGlyphs) ) glyphs = self.glyphs = {} for glyphID, glyphName in enumerate(self.glyphOrder): glyph = self._decodeGlyph(glyphID) glyphs[glyphName] = glyph def transform(self, ttFont): """Return transformed 'glyf' data""" self.numGlyphs = len(self.glyphs) assert len(self.glyphOrder) == self.numGlyphs if "maxp" in ttFont: ttFont["maxp"].numGlyphs = self.numGlyphs self.indexFormat = ttFont["head"].indexToLocFormat for stream in self.subStreams: setattr(self, stream, b"") bboxBitmapSize = ((self.numGlyphs + 31) >> 5) << 2 self.bboxBitmap = array.array("B", [0] * bboxBitmapSize) self.overlapSimpleBitmap = array.array("B", [0] * ((self.numGlyphs + 7) >> 3)) for glyphID in range(self.numGlyphs): try: self._encodeGlyph(glyphID) except NotImplementedError: return None hasOverlapSimpleBitmap = any(self.overlapSimpleBitmap) self.bboxStream = self.bboxBitmap.tobytes() + self.bboxStream for stream in self.subStreams: setattr(self, stream + "Size", len(getattr(self, stream))) self.version = 0 self.optionFlags = 0 if hasOverlapSimpleBitmap: self.optionFlags |= woff2OverlapSimpleBitmapFlag data = sstruct.pack(woff2GlyfTableFormat, self) data += bytesjoin([getattr(self, s) for s in self.subStreams]) if hasOverlapSimpleBitmap: data += self.overlapSimpleBitmap.tobytes() return data def _decodeGlyph(self, glyphID): glyph = getTableModule("glyf").Glyph() glyph.numberOfContours = self.nContourStream[glyphID] if glyph.numberOfContours == 0: return glyph elif glyph.isComposite(): self._decodeComponents(glyph) else: self._decodeCoordinates(glyph) self._decodeOverlapSimpleFlag(glyph, glyphID) self._decodeBBox(glyphID, glyph) return glyph def _decodeComponents(self, glyph): data = self.compositeStream glyph.components = [] more = 1 haveInstructions = 0 while more: component = getTableModule("glyf").GlyphComponent() more, haveInstr, data = component.decompile(data, self) haveInstructions = haveInstructions | haveInstr glyph.components.append(component) self.compositeStream = data if haveInstructions: self._decodeInstructions(glyph) def _decodeCoordinates(self, glyph): data = self.nPointsStream endPtsOfContours = [] endPoint = -1 for i in range(glyph.numberOfContours): ptsOfContour, data = unpack255UShort(data) endPoint += ptsOfContour endPtsOfContours.append(endPoint) glyph.endPtsOfContours = endPtsOfContours self.nPointsStream = data self._decodeTriplets(glyph) self._decodeInstructions(glyph) def _decodeOverlapSimpleFlag(self, glyph, glyphID): if self.overlapSimpleBitmap is None or glyph.numberOfContours <= 0: return byte = glyphID >> 3 bit = glyphID & 7 if self.overlapSimpleBitmap[byte] & (0x80 >> bit): glyph.flags[0] |= _g_l_y_f.flagOverlapSimple def _decodeInstructions(self, glyph): glyphStream = self.glyphStream instructionStream = self.instructionStream instructionLength, glyphStream = unpack255UShort(glyphStream) glyph.program = ttProgram.Program() glyph.program.fromBytecode(instructionStream[:instructionLength]) self.glyphStream = glyphStream self.instructionStream = instructionStream[instructionLength:] def _decodeBBox(self, glyphID, glyph): haveBBox = bool(self.bboxBitmap[glyphID >> 3] & (0x80 >> (glyphID & 7))) if glyph.isComposite() and not haveBBox: raise TTLibError("no bbox values for composite glyph %d" % glyphID) if haveBBox: dummy, self.bboxStream = sstruct.unpack2(bboxFormat, self.bboxStream, glyph) else: glyph.recalcBounds(self) def _decodeTriplets(self, glyph): def withSign(flag, baseval): assert 0 <= baseval and baseval < 65536, "integer overflow" return baseval if flag & 1 else -baseval nPoints = glyph.endPtsOfContours[-1] + 1 flagSize = nPoints if flagSize > len(self.flagStream): raise TTLibError("not enough 'flagStream' data") flagsData = self.flagStream[:flagSize] self.flagStream = self.flagStream[flagSize:] flags = array.array("B", flagsData) triplets = array.array("B", self.glyphStream) nTriplets = len(triplets) assert nPoints <= nTriplets x = 0 y = 0 glyph.coordinates = getTableModule("glyf").GlyphCoordinates.zeros(nPoints) glyph.flags = array.array("B") tripletIndex = 0 for i in range(nPoints): flag = flags[i] onCurve = not bool(flag >> 7) flag &= 0x7F if flag < 84: nBytes = 1 elif flag < 120: nBytes = 2 elif flag < 124: nBytes = 3 else: nBytes = 4 assert (tripletIndex + nBytes) <= nTriplets if flag < 10: dx = 0 dy = withSign(flag, ((flag & 14) << 7) + triplets[tripletIndex]) elif flag < 20: dx = withSign(flag, (((flag - 10) & 14) << 7) + triplets[tripletIndex]) dy = 0 elif flag < 84: b0 = flag - 20 b1 = triplets[tripletIndex] dx = withSign(flag, 1 + (b0 & 0x30) + (b1 >> 4)) dy = withSign(flag >> 1, 1 + ((b0 & 0x0C) << 2) + (b1 & 0x0F)) elif flag < 120: b0 = flag - 84 dx = withSign(flag, 1 + ((b0 // 12) << 8) + triplets[tripletIndex]) dy = withSign( flag >> 1, 1 + (((b0 % 12) >> 2) << 8) + triplets[tripletIndex + 1] ) elif flag < 124: b2 = triplets[tripletIndex + 1] dx = withSign(flag, (triplets[tripletIndex] << 4) + (b2 >> 4)) dy = withSign( flag >> 1, ((b2 & 0x0F) << 8) + triplets[tripletIndex + 2] ) else: dx = withSign( flag, (triplets[tripletIndex] << 8) + triplets[tripletIndex + 1] ) dy = withSign( flag >> 1, (triplets[tripletIndex + 2] << 8) + triplets[tripletIndex + 3], ) tripletIndex += nBytes x += dx y += dy glyph.coordinates[i] = (x, y) glyph.flags.append(int(onCurve)) bytesConsumed = tripletIndex self.glyphStream = self.glyphStream[bytesConsumed:] def _encodeGlyph(self, glyphID): glyphName = self.getGlyphName(glyphID) glyph = self[glyphName] self.nContourStream += struct.pack(">h", glyph.numberOfContours) if glyph.numberOfContours == 0: return elif glyph.isComposite(): self._encodeComponents(glyph) elif glyph.isVarComposite(): raise NotImplementedError else: self._encodeCoordinates(glyph) self._encodeOverlapSimpleFlag(glyph, glyphID) self._encodeBBox(glyphID, glyph) def _encodeComponents(self, glyph): lastcomponent = len(glyph.components) - 1 more = 1 haveInstructions = 0 for i in range(len(glyph.components)): if i == lastcomponent: haveInstructions = hasattr(glyph, "program") more = 0 component = glyph.components[i] self.compositeStream += component.compile(more, haveInstructions, self) if haveInstructions: self._encodeInstructions(glyph) def _encodeCoordinates(self, glyph): lastEndPoint = -1 if _g_l_y_f.flagCubic in glyph.flags: raise NotImplementedError for endPoint in glyph.endPtsOfContours: ptsOfContour = endPoint - lastEndPoint self.nPointsStream += pack255UShort(ptsOfContour) lastEndPoint = endPoint self._encodeTriplets(glyph) self._encodeInstructions(glyph) def _encodeOverlapSimpleFlag(self, glyph, glyphID): if glyph.numberOfContours <= 0: return if glyph.flags[0] & _g_l_y_f.flagOverlapSimple: byte = glyphID >> 3 bit = glyphID & 7 self.overlapSimpleBitmap[byte] |= 0x80 >> bit def _encodeInstructions(self, glyph): instructions = glyph.program.getBytecode() self.glyphStream += pack255UShort(len(instructions)) self.instructionStream += instructions def _encodeBBox(self, glyphID, glyph): assert glyph.numberOfContours != 0, "empty glyph has no bbox" if not glyph.isComposite(): # for simple glyphs, compare the encoded bounding box info with the calculated # values, and if they match omit the bounding box info currentBBox = glyph.xMin, glyph.yMin, glyph.xMax, glyph.yMax calculatedBBox = calcIntBounds(glyph.coordinates) if currentBBox == calculatedBBox: return self.bboxBitmap[glyphID >> 3] |= 0x80 >> (glyphID & 7) self.bboxStream += sstruct.pack(bboxFormat, glyph) def _encodeTriplets(self, glyph): assert len(glyph.coordinates) == len(glyph.flags) coordinates = glyph.coordinates.copy() coordinates.absoluteToRelative() flags = array.array("B") triplets = array.array("B") for i in range(len(coordinates)): onCurve = glyph.flags[i] & _g_l_y_f.flagOnCurve x, y = coordinates[i] absX = abs(x) absY = abs(y) onCurveBit = 0 if onCurve else 128 xSignBit = 0 if (x < 0) else 1 ySignBit = 0 if (y < 0) else 1 xySignBits = xSignBit + 2 * ySignBit if x == 0 and absY < 1280: flags.append(onCurveBit + ((absY & 0xF00) >> 7) + ySignBit) triplets.append(absY & 0xFF) elif y == 0 and absX < 1280: flags.append(onCurveBit + 10 + ((absX & 0xF00) >> 7) + xSignBit) triplets.append(absX & 0xFF) elif absX < 65 and absY < 65: flags.append( onCurveBit + 20 + ((absX - 1) & 0x30) + (((absY - 1) & 0x30) >> 2) + xySignBits ) triplets.append((((absX - 1) & 0xF) << 4) | ((absY - 1) & 0xF)) elif absX < 769 and absY < 769: flags.append( onCurveBit + 84 + 12 * (((absX - 1) & 0x300) >> 8) + (((absY - 1) & 0x300) >> 6) + xySignBits ) triplets.append((absX - 1) & 0xFF) triplets.append((absY - 1) & 0xFF) elif absX < 4096 and absY < 4096: flags.append(onCurveBit + 120 + xySignBits) triplets.append(absX >> 4) triplets.append(((absX & 0xF) << 4) | (absY >> 8)) triplets.append(absY & 0xFF) else: flags.append(onCurveBit + 124 + xySignBits) triplets.append(absX >> 8) triplets.append(absX & 0xFF) triplets.append(absY >> 8) triplets.append(absY & 0xFF) self.flagStream += flags.tobytes() self.glyphStream += triplets.tobytes() class WOFF2HmtxTable(getTableClass("hmtx")): def __init__(self, tag=None): self.tableTag = Tag(tag or "hmtx") def reconstruct(self, data, ttFont): (flags,) = struct.unpack(">B", data[:1]) data = data[1:] if flags & 0b11111100 != 0: raise TTLibError("Bits 2-7 of '%s' flags are reserved" % self.tableTag) # When bit 0 is _not_ set, the lsb[] array is present hasLsbArray = flags & 1 == 0 # When bit 1 is _not_ set, the leftSideBearing[] array is present hasLeftSideBearingArray = flags & 2 == 0 if hasLsbArray and hasLeftSideBearingArray: raise TTLibError( "either bits 0 or 1 (or both) must set in transformed '%s' flags" % self.tableTag ) glyfTable = ttFont["glyf"] headerTable = ttFont["hhea"] glyphOrder = glyfTable.glyphOrder numGlyphs = len(glyphOrder) numberOfHMetrics = min(int(headerTable.numberOfHMetrics), numGlyphs) assert len(data) >= 2 * numberOfHMetrics advanceWidthArray = array.array("H", data[: 2 * numberOfHMetrics]) if sys.byteorder != "big": advanceWidthArray.byteswap() data = data[2 * numberOfHMetrics :] if hasLsbArray: assert len(data) >= 2 * numberOfHMetrics lsbArray = array.array("h", data[: 2 * numberOfHMetrics]) if sys.byteorder != "big": lsbArray.byteswap() data = data[2 * numberOfHMetrics :] else: # compute (proportional) glyphs' lsb from their xMin lsbArray = array.array("h") for i, glyphName in enumerate(glyphOrder): if i >= numberOfHMetrics: break glyph = glyfTable[glyphName] xMin = getattr(glyph, "xMin", 0) lsbArray.append(xMin) numberOfSideBearings = numGlyphs - numberOfHMetrics if hasLeftSideBearingArray: assert len(data) >= 2 * numberOfSideBearings leftSideBearingArray = array.array("h", data[: 2 * numberOfSideBearings]) if sys.byteorder != "big": leftSideBearingArray.byteswap() data = data[2 * numberOfSideBearings :] else: # compute (monospaced) glyphs' leftSideBearing from their xMin leftSideBearingArray = array.array("h") for i, glyphName in enumerate(glyphOrder): if i < numberOfHMetrics: continue glyph = glyfTable[glyphName] xMin = getattr(glyph, "xMin", 0) leftSideBearingArray.append(xMin) if data: raise TTLibError("too much '%s' table data" % self.tableTag) self.metrics = {} for i in range(numberOfHMetrics): glyphName = glyphOrder[i] advanceWidth, lsb = advanceWidthArray[i], lsbArray[i] self.metrics[glyphName] = (advanceWidth, lsb) lastAdvance = advanceWidthArray[-1] for i in range(numberOfSideBearings): glyphName = glyphOrder[i + numberOfHMetrics] self.metrics[glyphName] = (lastAdvance, leftSideBearingArray[i]) def transform(self, ttFont): glyphOrder = ttFont.getGlyphOrder() glyf = ttFont["glyf"] hhea = ttFont["hhea"] numberOfHMetrics = hhea.numberOfHMetrics # check if any of the proportional glyphs has left sidebearings that # differ from their xMin bounding box values. hasLsbArray = False for i in range(numberOfHMetrics): glyphName = glyphOrder[i] lsb = self.metrics[glyphName][1] if lsb != getattr(glyf[glyphName], "xMin", 0): hasLsbArray = True break # do the same for the monospaced glyphs (if any) at the end of hmtx table hasLeftSideBearingArray = False for i in range(numberOfHMetrics, len(glyphOrder)): glyphName = glyphOrder[i] lsb = self.metrics[glyphName][1] if lsb != getattr(glyf[glyphName], "xMin", 0): hasLeftSideBearingArray = True break # if we need to encode both sidebearings arrays, then no transformation is # applicable, and we must use the untransformed hmtx data if hasLsbArray and hasLeftSideBearingArray: return # set bit 0 and 1 when the respective arrays are _not_ present flags = 0 if not hasLsbArray: flags |= 1 << 0 if not hasLeftSideBearingArray: flags |= 1 << 1 data = struct.pack(">B", flags) advanceWidthArray = array.array( "H", [ self.metrics[glyphName][0] for i, glyphName in enumerate(glyphOrder) if i < numberOfHMetrics ], ) if sys.byteorder != "big": advanceWidthArray.byteswap() data += advanceWidthArray.tobytes() if hasLsbArray: lsbArray = array.array( "h", [ self.metrics[glyphName][1] for i, glyphName in enumerate(glyphOrder) if i < numberOfHMetrics ], ) if sys.byteorder != "big": lsbArray.byteswap() data += lsbArray.tobytes() if hasLeftSideBearingArray: leftSideBearingArray = array.array( "h", [ self.metrics[glyphOrder[i]][1] for i in range(numberOfHMetrics, len(glyphOrder)) ], ) if sys.byteorder != "big": leftSideBearingArray.byteswap() data += leftSideBearingArray.tobytes() return data class WOFF2FlavorData(WOFFFlavorData): Flavor = "woff2" def __init__(self, reader=None, data=None, transformedTables=None): """Data class that holds the WOFF2 header major/minor version, any metadata or private data (as bytes strings), and the set of table tags that have transformations applied (if reader is not None), or will have once the WOFF2 font is compiled. Args: reader: an SFNTReader (or subclass) object to read flavor data from. data: another WOFFFlavorData object to initialise data from. transformedTables: set of strings containing table tags to be transformed. Raises: ImportError if the brotli module is not installed. NOTE: The 'reader' argument, on the one hand, and the 'data' and 'transformedTables' arguments, on the other hand, are mutually exclusive. """ if not haveBrotli: raise ImportError("No module named brotli") if reader is not None: if data is not None: raise TypeError("'reader' and 'data' arguments are mutually exclusive") if transformedTables is not None: raise TypeError( "'reader' and 'transformedTables' arguments are mutually exclusive" ) if transformedTables is not None and ( "glyf" in transformedTables and "loca" not in transformedTables or "loca" in transformedTables and "glyf" not in transformedTables ): raise ValueError("'glyf' and 'loca' must be transformed (or not) together") super(WOFF2FlavorData, self).__init__(reader=reader) if reader: transformedTables = [ tag for tag, entry in reader.tables.items() if entry.transformed ] elif data: self.majorVersion = data.majorVersion self.majorVersion = data.minorVersion self.metaData = data.metaData self.privData = data.privData if transformedTables is None and hasattr(data, "transformedTables"): transformedTables = data.transformedTables if transformedTables is None: transformedTables = woff2TransformedTableTags self.transformedTables = set(transformedTables) def _decompress(self, rawData): return brotli.decompress(rawData) def unpackBase128(data): r"""Read one to five bytes from UIntBase128-encoded input string, and return a tuple containing the decoded integer plus any leftover data. >>> unpackBase128(b'\x3f\x00\x00') == (63, b"\x00\x00") True >>> unpackBase128(b'\x8f\xff\xff\xff\x7f')[0] == 4294967295 True >>> unpackBase128(b'\x80\x80\x3f') # doctest: +IGNORE_EXCEPTION_DETAIL Traceback (most recent call last): File "", line 1, in ? TTLibError: UIntBase128 value must not start with leading zeros >>> unpackBase128(b'\x8f\xff\xff\xff\xff\x7f')[0] # doctest: +IGNORE_EXCEPTION_DETAIL Traceback (most recent call last): File "", line 1, in ? TTLibError: UIntBase128-encoded sequence is longer than 5 bytes >>> unpackBase128(b'\x90\x80\x80\x80\x00')[0] # doctest: +IGNORE_EXCEPTION_DETAIL Traceback (most recent call last): File "", line 1, in ? TTLibError: UIntBase128 value exceeds 2**32-1 """ if len(data) == 0: raise TTLibError("not enough data to unpack UIntBase128") result = 0 if byteord(data[0]) == 0x80: # font must be rejected if UIntBase128 value starts with 0x80 raise TTLibError("UIntBase128 value must not start with leading zeros") for i in range(woff2Base128MaxSize): if len(data) == 0: raise TTLibError("not enough data to unpack UIntBase128") code = byteord(data[0]) data = data[1:] # if any of the top seven bits are set then we're about to overflow if result & 0xFE000000: raise TTLibError("UIntBase128 value exceeds 2**32-1") # set current value = old value times 128 bitwise-or (byte bitwise-and 127) result = (result << 7) | (code & 0x7F) # repeat until the most significant bit of byte is false if (code & 0x80) == 0: # return result plus left over data return result, data # make sure not to exceed the size bound raise TTLibError("UIntBase128-encoded sequence is longer than 5 bytes") def base128Size(n): """Return the length in bytes of a UIntBase128-encoded sequence with value n. >>> base128Size(0) 1 >>> base128Size(24567) 3 >>> base128Size(2**32-1) 5 """ assert n >= 0 size = 1 while n >= 128: size += 1 n >>= 7 return size def packBase128(n): r"""Encode unsigned integer in range 0 to 2**32-1 (inclusive) to a string of bytes using UIntBase128 variable-length encoding. Produce the shortest possible encoding. >>> packBase128(63) == b"\x3f" True >>> packBase128(2**32-1) == b'\x8f\xff\xff\xff\x7f' True """ if n < 0 or n >= 2**32: raise TTLibError("UIntBase128 format requires 0 <= integer <= 2**32-1") data = b"" size = base128Size(n) for i in range(size): b = (n >> (7 * (size - i - 1))) & 0x7F if i < size - 1: b |= 0x80 data += struct.pack("B", b) return data def unpack255UShort(data): """Read one to three bytes from 255UInt16-encoded input string, and return a tuple containing the decoded integer plus any leftover data. >>> unpack255UShort(bytechr(252))[0] 252 Note that some numbers (e.g. 506) can have multiple encodings: >>> unpack255UShort(struct.pack("BB", 254, 0))[0] 506 >>> unpack255UShort(struct.pack("BB", 255, 253))[0] 506 >>> unpack255UShort(struct.pack("BBB", 253, 1, 250))[0] 506 """ code = byteord(data[:1]) data = data[1:] if code == 253: # read two more bytes as an unsigned short if len(data) < 2: raise TTLibError("not enough data to unpack 255UInt16") (result,) = struct.unpack(">H", data[:2]) data = data[2:] elif code == 254: # read another byte, plus 253 * 2 if len(data) == 0: raise TTLibError("not enough data to unpack 255UInt16") result = byteord(data[:1]) result += 506 data = data[1:] elif code == 255: # read another byte, plus 253 if len(data) == 0: raise TTLibError("not enough data to unpack 255UInt16") result = byteord(data[:1]) result += 253 data = data[1:] else: # leave as is if lower than 253 result = code # return result plus left over data return result, data def pack255UShort(value): r"""Encode unsigned integer in range 0 to 65535 (inclusive) to a bytestring using 255UInt16 variable-length encoding. >>> pack255UShort(252) == b'\xfc' True >>> pack255UShort(506) == b'\xfe\x00' True >>> pack255UShort(762) == b'\xfd\x02\xfa' True """ if value < 0 or value > 0xFFFF: raise TTLibError("255UInt16 format requires 0 <= integer <= 65535") if value < 253: return struct.pack(">B", value) elif value < 506: return struct.pack(">BB", 255, value - 253) elif value < 762: return struct.pack(">BB", 254, value - 506) else: return struct.pack(">BH", 253, value) def compress(input_file, output_file, transform_tables=None): """Compress OpenType font to WOFF2. Args: input_file: a file path, file or file-like object (open in binary mode) containing an OpenType font (either CFF- or TrueType-flavored). output_file: a file path, file or file-like object where to save the compressed WOFF2 font. transform_tables: Optional[Iterable[str]]: a set of table tags for which to enable preprocessing transformations. By default, only 'glyf' and 'loca' tables are transformed. An empty set means disable all transformations. """ log.info("Processing %s => %s" % (input_file, output_file)) font = TTFont(input_file, recalcBBoxes=False, recalcTimestamp=False) font.flavor = "woff2" if transform_tables is not None: font.flavorData = WOFF2FlavorData( data=font.flavorData, transformedTables=transform_tables ) font.save(output_file, reorderTables=False) def decompress(input_file, output_file): """Decompress WOFF2 font to OpenType font. Args: input_file: a file path, file or file-like object (open in binary mode) containing a compressed WOFF2 font. output_file: a file path, file or file-like object where to save the decompressed OpenType font. """ log.info("Processing %s => %s" % (input_file, output_file)) font = TTFont(input_file, recalcBBoxes=False, recalcTimestamp=False) font.flavor = None font.flavorData = None font.save(output_file, reorderTables=True) def main(args=None): """Compress and decompress WOFF2 fonts""" import argparse from fontTools import configLogger from fontTools.ttx import makeOutputFileName class _HelpAction(argparse._HelpAction): def __call__(self, parser, namespace, values, option_string=None): subparsers_actions = [ action for action in parser._actions if isinstance(action, argparse._SubParsersAction) ] for subparsers_action in subparsers_actions: for choice, subparser in subparsers_action.choices.items(): print(subparser.format_help()) parser.exit() class _NoGlyfTransformAction(argparse.Action): def __call__(self, parser, namespace, values, option_string=None): namespace.transform_tables.difference_update({"glyf", "loca"}) class _HmtxTransformAction(argparse.Action): def __call__(self, parser, namespace, values, option_string=None): namespace.transform_tables.add("hmtx") parser = argparse.ArgumentParser( prog="fonttools ttLib.woff2", description=main.__doc__, add_help=False ) parser.add_argument( "-h", "--help", action=_HelpAction, help="show this help message and exit" ) parser_group = parser.add_subparsers(title="sub-commands") parser_compress = parser_group.add_parser( "compress", description="Compress a TTF or OTF font to WOFF2" ) parser_decompress = parser_group.add_parser( "decompress", description="Decompress a WOFF2 font to OTF" ) for subparser in (parser_compress, parser_decompress): group = subparser.add_mutually_exclusive_group(required=False) group.add_argument( "-v", "--verbose", action="store_true", help="print more messages to console", ) group.add_argument( "-q", "--quiet", action="store_true", help="do not print messages to console", ) parser_compress.add_argument( "input_file", metavar="INPUT", help="the input OpenType font (.ttf or .otf)", ) parser_decompress.add_argument( "input_file", metavar="INPUT", help="the input WOFF2 font", ) parser_compress.add_argument( "-o", "--output-file", metavar="OUTPUT", help="the output WOFF2 font", ) parser_decompress.add_argument( "-o", "--output-file", metavar="OUTPUT", help="the output OpenType font", ) transform_group = parser_compress.add_argument_group() transform_group.add_argument( "--no-glyf-transform", dest="transform_tables", nargs=0, action=_NoGlyfTransformAction, help="Do not transform glyf (and loca) tables", ) transform_group.add_argument( "--hmtx-transform", dest="transform_tables", nargs=0, action=_HmtxTransformAction, help="Enable optional transformation for 'hmtx' table", ) parser_compress.set_defaults( subcommand=compress, transform_tables={"glyf", "loca"}, ) parser_decompress.set_defaults(subcommand=decompress) options = vars(parser.parse_args(args)) subcommand = options.pop("subcommand", None) if not subcommand: parser.print_help() return quiet = options.pop("quiet") verbose = options.pop("verbose") configLogger( level=("ERROR" if quiet else "DEBUG" if verbose else "INFO"), ) if not options["output_file"]: if subcommand is compress: extension = ".woff2" elif subcommand is decompress: # choose .ttf/.otf file extension depending on sfntVersion with open(options["input_file"], "rb") as f: f.seek(4) # skip 'wOF2' signature sfntVersion = f.read(4) assert len(sfntVersion) == 4, "not enough data" extension = ".otf" if sfntVersion == b"OTTO" else ".ttf" else: raise AssertionError(subcommand) options["output_file"] = makeOutputFileName( options["input_file"], outputDir=None, extension=extension ) try: subcommand(**options) except TTLibError as e: parser.error(e) if __name__ == "__main__": sys.exit(main())