def deserialize_custom_field(data: Optional[dict]) -> Optional[dict]:
"""
Handles deserialization of manifests inside the custom field dictionary
(e.g. from :class:`~lhotse.SupervisionSegment` or :class:`~lhotse.MonoCut`).
Mutates the input in-place, and returns it.
:param data: the contents of ``manifest.custom`` field.
:return: ``custom`` field dict with deserialized manifests (if any),
or None when input is None.
"""
if data is None:
return None
from lhotse.array import deserialize_array
# If any of the values in the input are also dicts,
# it indicates that might be a serialized array manifest.
# We'll try to deserialize it, and if there is an error,
# we'll just leave it as it was.
for key, value in data.items():
if isinstance(value, dict):
try:
data[key] = deserialize_array(value)
except:
pass
return data
def deserialize_item(data: dict) -> Any:
# Figures out what type of manifest is being decoded with some heuristics
# and returns a Lhotse manifest object rather than a raw dict.
from lhotse import Features, MonoCut, Recording, SupervisionSegment
from lhotse.array import deserialize_array
from lhotse.cut import MixedCut
if "shape" in data or "array" in data:
return deserialize_array(data)
if "sources" in data:
return Recording.from_dict(data)
if "num_features" in data:
return Features.from_dict(data)
if "type" not in data:
return SupervisionSegment.from_dict(data)
cut_type = data.pop("type")
if cut_type == "MonoCut":
return MonoCut.from_dict(data)
if cut_type == "Cut":
warnings.warn(
"Your manifest was created with Lhotse version earlier than v0.8, when MonoCut was called Cut. "
"Please re-generate it with Lhotse v0.8 as it might stop working in a future version "
"(using manifest.from_file() and then manifest.to_file() should be sufficient)."
)
return MonoCut.from_dict(data)
if cut_type == "MixedCut":
return MixedCut.from_dict(data)
raise ValueError(
f"Unexpected cut type during deserialization: '{cut_type}'")