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sane-sync-music: fix flac -> opus conversion for surround sound media

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Colin
2024-07-22 23:12:02 +00:00
parent 553a2724a4
commit a103cd819f
1 changed files with 24 additions and 10 deletions
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34
pkgs/additional/sane-scripts/src/sane-sync-music
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@@ -194,7 +194,7 @@ class Encoder:
def remove(self, path: Path) -> None:
self.destructive(None, os.remove, path)
def convert(self, source: Path, dest: Path, target_samplerate: int | None) -> None:
def convert(self, source: Path, dest: Path, target_samplerate: int | None, target_chancount: int | None) -> None:
logger.info(f'converting {source} -> {dest}')
codec_flags = []
@@ -204,12 +204,16 @@ class Encoder:
'-qscale:a', '0', # VBR0
]
elif dest.suffix == '.opus':
# opus defaults to 96 kbps for stereo (which is not enough IMO). 300-something for 5.1.
# recs: <https://wiki.xiph.org/Opus_Recommended_Settings>
# my chosen numbers don't have any particular significance, they just look nice :)
if target_chancount <= 2:
bps = 192000
else:
bps = 72000 * target_chancount
codec_flags = [
'-codec:a', 'libopus',
# opus defaults to 96 kbps for stereo (which is not enough IMO). 300-something for 5.1.
# no easy way to specify behavior which scales here AFAICT, so ... ?
# recs: <https://wiki.xiph.org/Opus_Recommended_Settings>
'-b:a', '192000',
'-b:a', str(bps),
]
if target_samplerate is not None:
# opus doesn't support 44.1 kHz, so use 48kHz instead.
@@ -224,6 +228,7 @@ class Encoder:
assert False, f'conversion to {dest.suffix} not yet supported'
samplerate_flags = ['-ar', str(target_samplerate)] if target_samplerate else []
chancount_flags = [ '-ac', str(target_chancount)] if target_chancount else []
self.check_output([
'ffmpeg',
@@ -231,12 +236,13 @@ class Encoder:
'-y', # force overwrite
'-i', str(source),
'-codec:v', 'copy',
] + codec_flags + samplerate_flags + [
] + codec_flags + samplerate_flags + chancount_flags + [
str(dest)
])
def cp_or_convert(self, source: Path, dest: Path) -> None:
source_samplerate = None
source_chancount = None
if source.suffix.lower() not in NON_AUDIO_FMTS:
try:
source_samplerate = int(
@@ -246,23 +252,31 @@ class Encoder:
quiet=True,
).decode("utf-8").strip()
)
source_chancount = int(
self.check_output(
['soxi', '-c', str(source)],
has_side_effect=False,
quiet=True,
).decode("utf-8").strip()
)
except:
if source.suffix.lower() in ['.aac', '.m4a', '.wma']:
# sox is known to not support these formats
logging.debug(f'unsupported extension for samplerate: {source}')
logging.debug(f'unsupported extension for samplerate/channelcount: {source}')
else:
logging.warning(f'unable to obtain samplerate for {source}')
logging.warning(f'unable to obtain samplerate/channelcount for {source}')
target_samplerate = self.prefs.desired_samplerate(source_samplerate)
target_chancount = source_chancount
if source_samplerate and not target_samplerate:
logging.warning(f'unable to map source sample rate: {source_samplerate}')
if source_samplerate != target_samplerate:
# resampling -> convert
self.convert(source, dest, target_samplerate)
self.convert(source, dest, target_samplerate, target_chancount)
elif source.suffix.lower() != dest.suffix:
# transcoding -> convert
self.convert(source, dest, target_samplerate)
self.convert(source, dest, target_samplerate, target_chancount)
else:
# neither resampling nor transcoding -> simple copy will suffice
self.cp(source, dest)