DeepSpeech/util/sample_collections.py
2020-03-10 10:32:58 +01:00

263 lines
10 KiB
Python

# -*- coding: utf-8 -*-
import os
import csv
import json
from pathlib import Path
from functools import partial
from util.helpers import MEGABYTE, GIGABYTE, Interleaved
from util.audio import Sample, DEFAULT_FORMAT, AUDIO_TYPE_WAV, AUDIO_TYPE_OPUS, SERIALIZABLE_AUDIO_TYPES
BIG_ENDIAN = 'big'
INT_SIZE = 4
BIGINT_SIZE = 2 * INT_SIZE
MAGIC = b'SAMPLEDB'
BUFFER_SIZE = 1 * MEGABYTE
CACHE_SIZE = 1 * GIGABYTE
SCHEMA_KEY = 'schema'
CONTENT_KEY = 'content'
MIME_TYPE_KEY = 'mime-type'
MIME_TYPE_TEXT = 'text/plain'
CONTENT_TYPE_SPEECH = 'speech'
CONTENT_TYPE_TRANSCRIPT = 'transcript'
class LabeledSample(Sample):
"""In-memory labeled audio sample representing an utterance.
Derived from util.audio.Sample and used by sample collection readers and writers."""
def __init__(self, audio_type, raw_data, transcript, audio_format=DEFAULT_FORMAT, sample_id=None):
"""
Creates an in-memory speech sample together with a transcript of the utterance (label).
:param audio_type: See util.audio.Sample.__init__ .
:param raw_data: See util.audio.Sample.__init__ .
:param transcript: Transcript of the sample's utterance
:param audio_format: See util.audio.Sample.__init__ .
:param sample_id: Tracking ID - typically assigned by collection readers
"""
super().__init__(audio_type, raw_data, audio_format=audio_format)
self.sample_id = sample_id
self.transcript = transcript
class DirectSDBWriter:
"""Sample collection writer for creating a Sample DB (SDB) file"""
def __init__(self, sdb_filename, buffering=BUFFER_SIZE, audio_type=AUDIO_TYPE_OPUS, id_prefix=None):
self.sdb_filename = sdb_filename
self.id_prefix = sdb_filename if id_prefix is None else id_prefix
if audio_type not in SERIALIZABLE_AUDIO_TYPES:
raise ValueError('Audio type "{}" not supported'.format(audio_type))
self.audio_type = audio_type
self.sdb_file = open(sdb_filename, 'wb', buffering=buffering)
self.offsets = []
self.num_samples = 0
self.sdb_file.write(MAGIC)
meta_data = {
SCHEMA_KEY: [
{CONTENT_KEY: CONTENT_TYPE_SPEECH, MIME_TYPE_KEY: audio_type},
{CONTENT_KEY: CONTENT_TYPE_TRANSCRIPT, MIME_TYPE_KEY: MIME_TYPE_TEXT}
]
}
meta_data = json.dumps(meta_data).encode()
self.write_big_int(len(meta_data))
self.sdb_file.write(meta_data)
self.offset_samples = self.sdb_file.tell()
self.sdb_file.seek(2 * BIGINT_SIZE, 1)
def write_int(self, n):
return self.sdb_file.write(n.to_bytes(INT_SIZE, BIG_ENDIAN))
def write_big_int(self, n):
return self.sdb_file.write(n.to_bytes(BIGINT_SIZE, BIG_ENDIAN))
def __enter__(self):
return self
def add(self, sample):
def to_bytes(n):
return n.to_bytes(INT_SIZE, BIG_ENDIAN)
sample.change_audio_type(self.audio_type)
opus = sample.audio.getbuffer()
opus_len = to_bytes(len(opus))
transcript = sample.transcript.encode()
transcript_len = to_bytes(len(transcript))
entry_len = to_bytes(len(opus_len) + len(opus) + len(transcript_len) + len(transcript))
buffer = b''.join([entry_len, opus_len, opus, transcript_len, transcript])
self.offsets.append(self.sdb_file.tell())
self.sdb_file.write(buffer)
sample.sample_id = '{}:{}'.format(self.id_prefix, self.num_samples)
self.num_samples += 1
return sample.sample_id
def close(self):
if self.sdb_file is None:
return
offset_index = self.sdb_file.tell()
self.sdb_file.seek(self.offset_samples)
self.write_big_int(offset_index - self.offset_samples - BIGINT_SIZE)
self.write_big_int(self.num_samples)
self.sdb_file.seek(offset_index + BIGINT_SIZE)
self.write_big_int(self.num_samples)
for offset in self.offsets:
self.write_big_int(offset)
offset_end = self.sdb_file.tell()
self.sdb_file.seek(offset_index)
self.write_big_int(offset_end - offset_index - BIGINT_SIZE)
self.sdb_file.close()
self.sdb_file = None
def __len__(self):
return len(self.offsets)
def __exit__(self, exc_type, exc_val, exc_tb):
self.close()
class SDB: # pylint: disable=too-many-instance-attributes
"""Sample collection reader for reading a Sample DB (SDB) file"""
def __init__(self, sdb_filename, buffering=BUFFER_SIZE, id_prefix=None):
self.sdb_filename = sdb_filename
self.id_prefix = sdb_filename if id_prefix is None else id_prefix
self.sdb_file = open(sdb_filename, 'rb', buffering=buffering)
self.offsets = []
if self.sdb_file.read(len(MAGIC)) != MAGIC:
raise RuntimeError('No Sample Database')
meta_chunk_len = self.read_big_int()
self.meta = json.loads(self.sdb_file.read(meta_chunk_len).decode())
if SCHEMA_KEY not in self.meta:
raise RuntimeError('Missing schema')
self.schema = self.meta[SCHEMA_KEY]
speech_columns = self.find_columns(content=CONTENT_TYPE_SPEECH, mime_type=SERIALIZABLE_AUDIO_TYPES)
if not speech_columns:
raise RuntimeError('No speech data (missing in schema)')
self.speech_index = speech_columns[0]
self.audio_type = self.schema[self.speech_index][MIME_TYPE_KEY]
transcript_columns = self.find_columns(content=CONTENT_TYPE_TRANSCRIPT, mime_type=MIME_TYPE_TEXT)
if not transcript_columns:
raise RuntimeError('No transcript data (missing in schema)')
self.transcript_index = transcript_columns[0]
sample_chunk_len = self.read_big_int()
self.sdb_file.seek(sample_chunk_len + BIGINT_SIZE, 1)
num_samples = self.read_big_int()
for _ in range(num_samples):
self.offsets.append(self.read_big_int())
def read_int(self):
return int.from_bytes(self.sdb_file.read(INT_SIZE), BIG_ENDIAN)
def read_big_int(self):
return int.from_bytes(self.sdb_file.read(BIGINT_SIZE), BIG_ENDIAN)
def find_columns(self, content=None, mime_type=None):
criteria = []
if content is not None:
criteria.append((CONTENT_KEY, content))
if mime_type is not None:
criteria.append((MIME_TYPE_KEY, mime_type))
if len(criteria) == 0:
raise ValueError('At least one of "content" or "mime-type" has to be provided')
matches = []
for index, column in enumerate(self.schema):
matched = 0
for field, value in criteria:
if column[field] == value or (isinstance(value, list) and column[field] in value):
matched += 1
if matched == len(criteria):
matches.append(index)
return matches
def read_row(self, row_index, *columns):
columns = list(columns)
column_data = [None] * len(columns)
found = 0
if not 0 <= row_index < len(self.offsets):
raise ValueError('Wrong sample index: {} - has to be between 0 and {}'
.format(row_index, len(self.offsets) - 1))
self.sdb_file.seek(self.offsets[row_index] + INT_SIZE)
for index in range(len(self.schema)):
chunk_len = self.read_int()
if index in columns:
column_data[columns.index(index)] = self.sdb_file.read(chunk_len)
found += 1
if found == len(columns):
return tuple(column_data)
else:
self.sdb_file.seek(chunk_len, 1)
return tuple(column_data)
def __getitem__(self, i):
audio_data, transcript = self.read_row(i, self.speech_index, self.transcript_index)
transcript = transcript.decode()
sample_id = '{}:{}'.format(self.id_prefix, i)
return LabeledSample(self.audio_type, audio_data, transcript, sample_id=sample_id)
def __iter__(self):
for i in range(len(self.offsets)):
yield self[i]
def __len__(self):
return len(self.offsets)
def close(self):
if self.sdb_file is not None:
self.sdb_file.close()
def __del__(self):
self.close()
class CSV:
"""Sample collection reader for reading a DeepSpeech CSV file"""
def __init__(self, csv_filename):
self.csv_filename = csv_filename
self.rows = []
csv_dir = Path(csv_filename).parent
with open(csv_filename, 'r', encoding='utf8') as csv_file:
reader = csv.DictReader(csv_file)
for row in reader:
wav_filename = Path(row['wav_filename'])
if not wav_filename.is_absolute():
wav_filename = csv_dir / wav_filename
self.rows.append((str(wav_filename), int(row['wav_filesize']), row['transcript']))
self.rows.sort(key=lambda r: r[1])
def __getitem__(self, i):
wav_filename, _, transcript = self.rows[i]
with open(wav_filename, 'rb') as wav_file:
return LabeledSample(AUDIO_TYPE_WAV, wav_file.read(), transcript, sample_id=wav_filename)
def __iter__(self):
for i in range(len(self.rows)):
yield self[i]
def __len__(self):
return len(self.rows)
def samples_from_file(filename, buffering=BUFFER_SIZE):
"""Returns an iterable of LabeledSample objects loaded from a file."""
ext = os.path.splitext(filename)[1].lower()
if ext == '.sdb':
return SDB(filename, buffering=buffering)
if ext == '.csv':
return CSV(filename)
raise ValueError('Unknown file type: "{}"'.format(ext))
def samples_from_files(filenames, buffering=BUFFER_SIZE):
"""Returns an iterable of LabeledSample objects from a list of files."""
if len(filenames) == 0:
raise ValueError('No files')
if len(filenames) == 1:
return samples_from_file(filenames[0], buffering=buffering)
cols = list(map(partial(samples_from_file, buffering=buffering), filenames))
return Interleaved(*cols, key=lambda s: s.duration)