--- a/eric6/ThirdParty/CharDet/chardet/sbcharsetprober.py Tue Apr 20 19:47:39 2021 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,145 +0,0 @@ -######################## BEGIN LICENSE BLOCK ######################## -# The Original Code is Mozilla Universal charset detector code. -# -# The Initial Developer of the Original Code is -# Netscape Communications Corporation. -# Portions created by the Initial Developer are Copyright (C) 2001 -# the Initial Developer. All Rights Reserved. -# -# Contributor(s): -# Mark Pilgrim - port to Python -# Shy Shalom - original C code -# -# This library is free software; you can redistribute it and/or -# modify it under the terms of the GNU Lesser General Public -# License as published by the Free Software Foundation; either -# version 2.1 of the License, or (at your option) any later version. -# -# This library is distributed in the hope that it will be useful, -# but WITHOUT ANY WARRANTY; without even the implied warranty of -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -# Lesser General Public License for more details. -# -# You should have received a copy of the GNU Lesser General Public -# License along with this library; if not, write to the Free Software -# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA -# 02110-1301 USA -######################### END LICENSE BLOCK ######################### - -from collections import namedtuple - -from .charsetprober import CharSetProber -from .enums import CharacterCategory, ProbingState, SequenceLikelihood - - -SingleByteCharSetModel = namedtuple('SingleByteCharSetModel', - ['charset_name', - 'language', - 'char_to_order_map', - 'language_model', - 'typical_positive_ratio', - 'keep_ascii_letters', - 'alphabet']) - - -class SingleByteCharSetProber(CharSetProber): - SAMPLE_SIZE = 64 - SB_ENOUGH_REL_THRESHOLD = 1024 # 0.25 * SAMPLE_SIZE^2 - POSITIVE_SHORTCUT_THRESHOLD = 0.95 - NEGATIVE_SHORTCUT_THRESHOLD = 0.05 - - def __init__(self, model, reversed=False, name_prober=None): - super(SingleByteCharSetProber, self).__init__() - self._model = model - # TRUE if we need to reverse every pair in the model lookup - self._reversed = reversed - # Optional auxiliary prober for name decision - self._name_prober = name_prober - self._last_order = None - self._seq_counters = None - self._total_seqs = None - self._total_char = None - self._freq_char = None - self.reset() - - def reset(self): - super(SingleByteCharSetProber, self).reset() - # char order of last character - self._last_order = 255 - self._seq_counters = [0] * SequenceLikelihood.get_num_categories() - self._total_seqs = 0 - self._total_char = 0 - # characters that fall in our sampling range - self._freq_char = 0 - - @property - def charset_name(self): - if self._name_prober: - return self._name_prober.charset_name - else: - return self._model.charset_name - - @property - def language(self): - if self._name_prober: - return self._name_prober.language - else: - return self._model.language - - def feed(self, byte_str): - # TODO: Make filter_international_words keep things in self.alphabet - if not self._model.keep_ascii_letters: - byte_str = self.filter_international_words(byte_str) - if not byte_str: - return self.state - char_to_order_map = self._model.char_to_order_map - language_model = self._model.language_model - for char in byte_str: - order = char_to_order_map.get(char, CharacterCategory.UNDEFINED) - # XXX: This was SYMBOL_CAT_ORDER before, with a value of 250, but - # CharacterCategory.SYMBOL is actually 253, so we use CONTROL - # to make it closer to the original intent. The only difference - # is whether or not we count digits and control characters for - # _total_char purposes. - if order < CharacterCategory.CONTROL: - self._total_char += 1 - # TODO: Follow uchardet's lead and discount confidence for frequent - # control characters. - # See https://github.com/BYVoid/uchardet/commit/55b4f23971db61 - if order < self.SAMPLE_SIZE: - self._freq_char += 1 - if self._last_order < self.SAMPLE_SIZE: - self._total_seqs += 1 - if not self._reversed: - lm_cat = language_model[self._last_order][order] - else: - lm_cat = language_model[order][self._last_order] - self._seq_counters[lm_cat] += 1 - self._last_order = order - - charset_name = self._model.charset_name - if self.state == ProbingState.DETECTING: - if self._total_seqs > self.SB_ENOUGH_REL_THRESHOLD: - confidence = self.get_confidence() - if confidence > self.POSITIVE_SHORTCUT_THRESHOLD: - self.logger.debug('%s confidence = %s, we have a winner', - charset_name, confidence) - self._state = ProbingState.FOUND_IT - elif confidence < self.NEGATIVE_SHORTCUT_THRESHOLD: - self.logger.debug('%s confidence = %s, below negative ' - 'shortcut threshhold %s', charset_name, - confidence, - self.NEGATIVE_SHORTCUT_THRESHOLD) - self._state = ProbingState.NOT_ME - - return self.state - - def get_confidence(self): - r = 0.01 - if self._total_seqs > 0: - r = ((1.0 * self._seq_counters[SequenceLikelihood.POSITIVE]) / - self._total_seqs / self._model.typical_positive_ratio) - r = r * self._freq_char / self._total_char - if r >= 1.0: - r = 0.99 - return r