rishiraj's picture
add audio extractor
a647c50
import torch
import numpy as np
from torchaudio import functional as F
from transformers.pipelines.audio_utils import ffmpeg_read
from starlette.exceptions import HTTPException
import sys
# Code from insanely-fast-whisper:
# https://github.com/Vaibhavs10/insanely-fast-whisper
import logging
logger = logging.getLogger(__name__)
def preprocess_inputs(inputs, sampling_rate):
inputs = ffmpeg_read(inputs, sampling_rate)
if sampling_rate != 16000:
inputs = F.resample(
torch.from_numpy(inputs), sampling_rate, 16000
).numpy()
if len(inputs.shape) != 1:
logger.error(f"Diarization pipeline expecs single channel audio, received {inputs.shape}")
raise HTTPException(
status_code=400,
detail=f"Diarization pipeline expecs single channel audio, received {inputs.shape}"
)
# diarization model expects float32 torch tensor of shape `(channels, seq_len)`
diarizer_inputs = torch.from_numpy(inputs).float()
diarizer_inputs = diarizer_inputs.unsqueeze(0)
return inputs, diarizer_inputs
def diarize_audio(diarizer_inputs, diarization_pipeline, parameters):
diarization = diarization_pipeline(
{"waveform": diarizer_inputs, "sample_rate": parameters.sampling_rate},
num_speakers=parameters.num_speakers,
min_speakers=parameters.min_speakers,
max_speakers=parameters.max_speakers,
)
segments = []
for segment, track, label in diarization.itertracks(yield_label=True):
segments.append(
{
"segment": {"start": segment.start, "end": segment.end},
"track": track,
"label": label,
}
)
# diarizer output may contain consecutive segments from the same speaker (e.g. {(0 -> 1, speaker_1), (1 -> 1.5, speaker_1), ...})
# we combine these segments to give overall timestamps for each speaker's turn (e.g. {(0 -> 1.5, speaker_1), ...})
new_segments = []
prev_segment = cur_segment = segments[0]
for i in range(1, len(segments)):
cur_segment = segments[i]
# check if we have changed speaker ("label")
if cur_segment["label"] != prev_segment["label"] and i < len(segments):
# add the start/end times for the super-segment to the new list
new_segments.append(
{
"segment": {
"start": prev_segment["segment"]["start"],
"end": cur_segment["segment"]["start"],
},
"speaker": prev_segment["label"],
}
)
prev_segment = segments[i]
# add the last segment(s) if there was no speaker change
new_segments.append(
{
"segment": {
"start": prev_segment["segment"]["start"],
"end": cur_segment["segment"]["end"],
},
"speaker": prev_segment["label"],
}
)
return new_segments
def post_process_segments_and_transcripts(new_segments, transcript, group_by_speaker) -> list:
# get the end timestamps for each chunk from the ASR output
end_timestamps = np.array(
[chunk["timestamp"][-1] if chunk["timestamp"][-1] is not None else sys.float_info.max for chunk in transcript])
segmented_preds = []
# align the diarizer timestamps and the ASR timestamps
for segment in new_segments:
# get the diarizer end timestamp
end_time = segment["segment"]["end"]
# find the ASR end timestamp that is closest to the diarizer's end timestamp and cut the transcript to here
upto_idx = np.argmin(np.abs(end_timestamps - end_time))
if group_by_speaker:
segmented_preds.append(
{
"speaker": segment["speaker"],
"text": "".join(
[chunk["text"] for chunk in transcript[: upto_idx + 1]]
),
"timestamp": (
transcript[0]["timestamp"][0],
transcript[upto_idx]["timestamp"][1],
),
}
)
else:
for i in range(upto_idx + 1):
segmented_preds.append({"speaker": segment["speaker"], **transcript[i]})
# crop the transcripts and timestamp lists according to the latest timestamp (for faster argmin)
transcript = transcript[upto_idx + 1:]
end_timestamps = end_timestamps[upto_idx + 1:]
if len(end_timestamps) == 0:
break
return segmented_preds
def diarize(diarization_pipeline, file, parameters, asr_outputs):
_, diarizer_inputs = preprocess_inputs(file, parameters.sampling_rate)
segments = diarize_audio(
diarizer_inputs,
diarization_pipeline,
parameters
)
return post_process_segments_and_transcripts(
segments, asr_outputs["chunks"], group_by_speaker=False
)