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dbf8921 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 | # Copyright (c) Meta Platforms, Inc. and affiliates.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import bisect
from typing import Any, Dict, List, Optional, Tuple
from projectaria_tools.core.sensor_data import TimeQueryOptions # @manual
def query_left_right(ordered_timestamps: List, query_timestamp: int):
"""
Return the left and right timestamp of the query timestamp by using bisection.
Assumption: timestamps are monotonically sorted in the ordered_timestamps List
"""
idx = bisect.bisect_left(ordered_timestamps, query_timestamp)
if idx == 0:
lower_timestamp = None
else:
lower_timestamp = ordered_timestamps[idx - 1]
if idx == len(ordered_timestamps):
upper_timestamp = None
else:
upper_timestamp = ordered_timestamps[idx]
if lower_timestamp is not None and upper_timestamp is not None:
alpha = (query_timestamp - lower_timestamp) / (
upper_timestamp - lower_timestamp
)
else:
alpha = None
return lower_timestamp, upper_timestamp, alpha
def lookup_timestamp(
time_indexed_dict: Dict[int, Any],
sorted_timestamp_list: Optional[List[int]],
query_timestamp: int,
time_query_options: TimeQueryOptions,
) -> Tuple[Any, int]:
"""
Lookup the object corresponding to query_timestamp based on the time_query_options.
time_indexed_dict: a dictionary of timestamp to object
sorted_timestamp_list: a precomputed list of sorted timestamps in time_indexed_dict. If None, it will be computed from time_indexed_dict.
query_timestamp: the timestamp to query
time_query_options: the time query options to use (CLOSEST, BEFORE, AFTER)
"""
if sorted_timestamp_list is None:
sorted_timestamp_list = sorted(time_indexed_dict.keys())
obj = None
time_delta_ns = None
if query_timestamp in time_indexed_dict:
obj = time_indexed_dict[query_timestamp]
time_delta_ns = 0
else:
left_frame_tsns, right_frame_tsns, alpha = query_left_right(
ordered_timestamps=sorted_timestamp_list,
query_timestamp=query_timestamp,
)
if time_query_options == TimeQueryOptions.BEFORE:
if left_frame_tsns is not None:
obj = time_indexed_dict[left_frame_tsns]
time_delta_ns = query_timestamp - left_frame_tsns
elif time_query_options == TimeQueryOptions.AFTER:
if right_frame_tsns is not None:
obj = time_indexed_dict[right_frame_tsns]
time_delta_ns = query_timestamp - right_frame_tsns
elif time_query_options == TimeQueryOptions.CLOSEST:
if left_frame_tsns is not None and right_frame_tsns is not None:
if abs(query_timestamp - left_frame_tsns) > abs(
query_timestamp - right_frame_tsns
):
obj = time_indexed_dict[right_frame_tsns]
time_delta_ns = query_timestamp - right_frame_tsns
else:
obj = time_indexed_dict[left_frame_tsns]
time_delta_ns = query_timestamp - left_frame_tsns
elif left_frame_tsns is not None:
obj = time_indexed_dict[left_frame_tsns]
time_delta_ns = query_timestamp - left_frame_tsns
elif right_frame_tsns is not None:
obj = time_indexed_dict[right_frame_tsns]
time_delta_ns = query_timestamp - right_frame_tsns
return obj, time_delta_ns
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