def EXACT_SILENCE_PCM_Reader(pcm_frames,
sample_rate=44100,
channels=2,
bits_per_sample=16,
channel_mask=None):
from audiotools.decoders import SameSample
if channel_mask is None:
channel_mask = int(audiotools.ChannelMask.from_channels(channels))
return SameSample(sample=0,
total_pcm_frames=pcm_frames,
sample_rate=sample_rate,
channels=channels,
channel_mask=channel_mask,
bits_per_sample=bits_per_sample)
def BLANK_PCM_Reader(length,
sample_rate=44100,
channels=2,
bits_per_sample=16,
channel_mask=None):
from audiotools.decoders import SameSample
if channel_mask is None:
channel_mask = int(audiotools.ChannelMask.from_channels(channels))
return SameSample(sample=1,
total_pcm_frames=length * sample_rate,
sample_rate=sample_rate,
channels=channels,
channel_mask=channel_mask,
bits_per_sample=bits_per_sample)
def accuraterip_checksum(progress, track, previous_track, next_track,
ar_matches):
from audiotools import (transfer_data, PCMCat, PCMReaderHead,
PCMReaderDeHead, PCMReaderProgress)
from audiotools.decoders import SameSample
from audiotools.accuraterip import Checksum, match_offset
# unify previous track, current track and next track into a single stream
pcmreaders = []
if previous_track is not None:
frames_to_skip = previous_track.total_frames() - PREVIOUS_TRACK_FRAMES
prev_pcmreader = previous_track.to_pcm()
if hasattr(prev_pcmreader, "seek") and callable(prev_pcmreader.seek):
frames_to_skip -= prev_pcmreader.seek(frames_to_skip)
pcmreaders.append(PCMReaderDeHead(prev_pcmreader, frames_to_skip))
else:
pcmreaders.append(
SameSample(sample=0,
total_pcm_frames=PREVIOUS_TRACK_FRAMES,
sample_rate=track.sample_rate(),
channels=track.channels(),
channel_mask=int(track.channel_mask()),
bits_per_sample=track.bits_per_sample()))
pcmreaders.append(track.to_pcm())
if next_track is not None:
pcmreaders.append(PCMReaderHead(next_track.to_pcm(),
NEXT_TRACK_FRAMES))
else:
pcmreaders.append(
SameSample(sample=0,
total_pcm_frames=NEXT_TRACK_FRAMES,
sample_rate=track.sample_rate(),
channels=track.channels(),
channel_mask=int(track.channel_mask()),
bits_per_sample=track.bits_per_sample()))
# feed stream to checksummer
checksummer = Checksum(total_pcm_frames=track.total_frames(),
sample_rate=track.sample_rate(),
is_first=(previous_track is None),
is_last=(next_track is None),
pcm_frame_range=PREVIOUS_TRACK_FRAMES + 1 +
NEXT_TRACK_FRAMES,
accurateripv2_offset=PREVIOUS_TRACK_FRAMES)
try:
pcmreader = PCMReaderProgress(
PCMCat(pcmreaders),
PREVIOUS_TRACK_FRAMES + track.total_frames() + NEXT_TRACK_FRAMES,
progress)
audiotools.transfer_data(pcmreader.read, checksummer.update)
except (IOError, ValueError) as err:
return {
"filename": audiotools.Filename(track.filename).__unicode__(),
"error": str(err),
"v1": {
"checksum": None,
"offset": None,
"confidence": None
},
"v2": {
"checksum": None,
"offset": None,
"confidence": None
}
}
# determine checksum, confidence and offset from
# the calculated checksums and possible AccurateRip matches
(checksum_v2, confidence_v2,
offset_v2) = match_offset(ar_matches,
checksums=[checksummer.checksum_v2()],
initial_offset=0)
(checksum_v1, confidence_v1,
offset_v1) = match_offset(ar_matches=ar_matches,
checksums=checksummer.checksums_v1(),
initial_offset=-PREVIOUS_TRACK_FRAMES)
if len(ar_matches) == 0:
return {
"filename": audiotools.Filename(track.filename).__unicode__(),
"error": None,
"v1": {
"checksum": checksum_v1,
"offset": offset_v1,
"confidence": AR_NOT_FOUND
},
"v2": {
"checksum": checksum_v2,
"offset": offset_v2,
"confidence": AR_NOT_FOUND
}
}
else:
return {
"filename": audiotools.Filename(track.filename).__unicode__(),
"error": None,
"v1": {
"checksum":
checksum_v1,
"offset":
offset_v1,
"confidence": (confidence_v1 if
(confidence_v1 is not None) else AR_MISMATCH)
},
"v2": {
"checksum":
checksum_v2,
"offset":
offset_v2,
"confidence": (confidence_v2 if
(confidence_v2 is not None) else AR_MISMATCH)
}
}