250 lines
7.6 KiB
Python
250 lines
7.6 KiB
Python
"""Decode RoboSense H32 MSOP packets into Cartesian frames (metres).
|
|
|
|
Angle / distance conventions follow the H32 Medulla plugins:
|
|
azimuth = normalize(-(block_az + horizontal[ch])), altitude = vertical[ch],
|
|
distance_mm = raw * distance_unit_mm, then:
|
|
|
|
x = d_m * cos(alt) * cos(az)
|
|
y = d_m * cos(alt) * sin(az)
|
|
z = d_m * sin(alt)
|
|
|
|
When DIFOP is unavailable, vertical angles default to a uniform -16°…+16° fan
|
|
and horizontal channel offsets default to 0.
|
|
"""
|
|
|
|
from __future__ import annotations
|
|
|
|
from dataclasses import dataclass
|
|
from typing import Iterable
|
|
|
|
import numpy as np
|
|
|
|
from .capture_format_v2 import CaptureFile
|
|
|
|
PACKET_LENGTH = 1248
|
|
DATA_START = 42
|
|
BLOCKS = 12
|
|
BLOCK_LENGTH = 100
|
|
CHANNELS = 32
|
|
MIN_FRAME_POINTS_DEFAULT = 100
|
|
|
|
|
|
def default_vertical_deg() -> np.ndarray:
|
|
return -16.0 + np.arange(CHANNELS, dtype=np.float64) * (32.0 / (CHANNELS - 1))
|
|
|
|
|
|
def default_horizontal_deg() -> np.ndarray:
|
|
return np.zeros(CHANNELS, dtype=np.float64)
|
|
|
|
|
|
def read_u16_be(packet: bytes, index: int) -> int:
|
|
return (packet[index] << 8) | packet[index + 1]
|
|
|
|
|
|
def device_timestamp_ms(packet: bytes) -> int:
|
|
seconds = int.from_bytes(packet[20:26], "big")
|
|
microseconds = int.from_bytes(packet[26:30], "big")
|
|
return seconds * 1000 + microseconds // 1000
|
|
|
|
|
|
def distance_unit_mm(packet: bytes, *, auto: bool = True, fallback: float = 2.5) -> float:
|
|
if not auto:
|
|
return float(fallback)
|
|
return 2.5 if packet[17] == 1 else 0.5
|
|
|
|
|
|
def normalize_azimuth_deg(angle: float) -> float:
|
|
while angle > 180.0:
|
|
angle -= 360.0
|
|
while angle < -180.0:
|
|
angle += 360.0
|
|
return angle
|
|
|
|
|
|
@dataclass
|
|
class LidarFrameExport:
|
|
t_start_s: float
|
|
t_end_s: float
|
|
points_xyz: np.ndarray # (N, 3) metres
|
|
|
|
|
|
def decode_packet_points(
|
|
packet: bytes,
|
|
vertical_deg: np.ndarray,
|
|
horizontal_deg: np.ndarray,
|
|
*,
|
|
min_range_m: float = 0.3,
|
|
max_range_m: float = 120.0,
|
|
) -> tuple[list[float], np.ndarray]:
|
|
"""Decode one MSOP packet into block azimuths and concatenated XYZ points."""
|
|
|
|
if len(packet) != PACKET_LENGTH:
|
|
return [], np.zeros((0, 3), dtype=np.float64)
|
|
unit = distance_unit_mm(packet)
|
|
az_list: list[float] = []
|
|
chunks: list[np.ndarray] = []
|
|
idx = DATA_START
|
|
for _block in range(BLOCKS):
|
|
if idx + BLOCK_LENGTH > PACKET_LENGTH or packet[idx] != 255 or packet[idx + 1] != 238:
|
|
break
|
|
az = read_u16_be(packet, idx + 2) * 0.01
|
|
az_list.append(az)
|
|
pts = _block_points(
|
|
packet,
|
|
idx,
|
|
az,
|
|
unit,
|
|
vertical_deg,
|
|
horizontal_deg,
|
|
min_range_m=min_range_m,
|
|
max_range_m=max_range_m,
|
|
)
|
|
if pts.shape[0]:
|
|
chunks.append(pts)
|
|
idx += BLOCK_LENGTH
|
|
if not chunks:
|
|
return az_list, np.zeros((0, 3), dtype=np.float64)
|
|
return az_list, np.vstack(chunks)
|
|
|
|
|
|
def _block_points(
|
|
packet: bytes,
|
|
block_offset: int,
|
|
az_deg: float,
|
|
unit_mm: float,
|
|
vertical_deg: np.ndarray,
|
|
horizontal_deg: np.ndarray,
|
|
*,
|
|
min_range_m: float,
|
|
max_range_m: float,
|
|
) -> np.ndarray:
|
|
xs: list[float] = []
|
|
ys: list[float] = []
|
|
zs: list[float] = []
|
|
idx = block_offset + 4 # after FF EE + azimuth
|
|
for ch in range(CHANNELS):
|
|
raw = read_u16_be(packet, idx)
|
|
idx += 3
|
|
if raw == 0:
|
|
continue
|
|
d_m = (raw * unit_mm) * 0.001
|
|
if d_m < min_range_m or d_m > max_range_m:
|
|
continue
|
|
az_ch = np.deg2rad(normalize_azimuth_deg(-(az_deg + float(horizontal_deg[ch]))))
|
|
alt = np.deg2rad(float(vertical_deg[ch]))
|
|
cos_alt = np.cos(alt)
|
|
xs.append(d_m * cos_alt * np.cos(az_ch))
|
|
ys.append(d_m * cos_alt * np.sin(az_ch))
|
|
zs.append(d_m * np.sin(alt))
|
|
if not xs:
|
|
return np.zeros((0, 3), dtype=np.float64)
|
|
return np.column_stack([xs, ys, zs]).astype(np.float64, copy=False)
|
|
|
|
|
|
def iter_h32_frames_from_packets(
|
|
packets: Iterable[bytes],
|
|
*,
|
|
min_frame_points: int = MIN_FRAME_POINTS_DEFAULT,
|
|
frame_stride: int = 1,
|
|
min_range_m: float = 0.3,
|
|
max_range_m: float = 120.0,
|
|
max_points_per_frame: int | None = None,
|
|
vertical_deg: np.ndarray | None = None,
|
|
horizontal_deg: np.ndarray | None = None,
|
|
) -> list[LidarFrameExport]:
|
|
"""Assemble raw MSOP packets into frames using the 270°→90° azimuth wrap."""
|
|
|
|
vertical = default_vertical_deg() if vertical_deg is None else np.asarray(vertical_deg, dtype=np.float64)
|
|
horizontal = default_horizontal_deg() if horizontal_deg is None else np.asarray(horizontal_deg, dtype=np.float64)
|
|
if vertical.shape != (CHANNELS,) or horizontal.shape != (CHANNELS,):
|
|
raise ValueError(f"vertical/horizontal must have shape ({CHANNELS},)")
|
|
|
|
frames: list[LidarFrameExport] = []
|
|
point_chunks: list[np.ndarray] = []
|
|
t_start: float | None = None
|
|
t_end: float | None = None
|
|
prev_az: float | None = None
|
|
kept = 0
|
|
stride = max(1, int(frame_stride))
|
|
|
|
def emit() -> None:
|
|
nonlocal point_chunks, t_start, t_end, kept
|
|
if not point_chunks or t_start is None or t_end is None:
|
|
point_chunks = []
|
|
t_start = t_end = None
|
|
return
|
|
points = np.vstack(point_chunks)
|
|
point_chunks = []
|
|
start_s, end_s = t_start, t_end
|
|
t_start = t_end = None
|
|
if points.shape[0] < min_frame_points:
|
|
return
|
|
if kept % stride != 0:
|
|
kept += 1
|
|
return
|
|
kept += 1
|
|
if max_points_per_frame is not None and points.shape[0] > max_points_per_frame:
|
|
select = np.linspace(0, points.shape[0] - 1, max_points_per_frame, dtype=int)
|
|
points = points[select]
|
|
if end_s <= start_s:
|
|
end_s = start_s + 0.1
|
|
frames.append(LidarFrameExport(t_start_s=start_s, t_end_s=end_s, points_xyz=points))
|
|
|
|
for packet in packets:
|
|
if len(packet) != PACKET_LENGTH:
|
|
continue
|
|
packet_t = device_timestamp_ms(packet) * 1e-3
|
|
unit = distance_unit_mm(packet)
|
|
idx = DATA_START
|
|
for _block in range(BLOCKS):
|
|
if idx + BLOCK_LENGTH > PACKET_LENGTH or packet[idx] != 255 or packet[idx + 1] != 238:
|
|
break
|
|
az = read_u16_be(packet, idx + 2) * 0.01
|
|
if prev_az is not None and prev_az > 270.0 and az < 90.0:
|
|
emit()
|
|
prev_az = az
|
|
pts = _block_points(
|
|
packet,
|
|
idx,
|
|
az,
|
|
unit,
|
|
vertical,
|
|
horizontal,
|
|
min_range_m=min_range_m,
|
|
max_range_m=max_range_m,
|
|
)
|
|
if pts.shape[0]:
|
|
if t_start is None:
|
|
t_start = packet_t
|
|
t_end = packet_t
|
|
point_chunks.append(pts)
|
|
idx += BLOCK_LENGTH
|
|
|
|
emit()
|
|
return frames
|
|
|
|
|
|
def iter_h32_frames(
|
|
capture: CaptureFile,
|
|
*,
|
|
min_frame_points: int = MIN_FRAME_POINTS_DEFAULT,
|
|
frame_stride: int = 1,
|
|
min_range_m: float = 0.3,
|
|
max_range_m: float = 120.0,
|
|
max_points_per_frame: int | None = None,
|
|
vertical_deg: np.ndarray | None = None,
|
|
horizontal_deg: np.ndarray | None = None,
|
|
) -> list[LidarFrameExport]:
|
|
"""Assemble MSOP packets from a V2 .rscap capture into frames."""
|
|
|
|
return iter_h32_frames_from_packets(
|
|
(chunk.raw for chunk in capture.chunks),
|
|
min_frame_points=min_frame_points,
|
|
frame_stride=frame_stride,
|
|
min_range_m=min_range_m,
|
|
max_range_m=max_range_m,
|
|
max_points_per_frame=max_points_per_frame,
|
|
vertical_deg=vertical_deg,
|
|
horizontal_deg=horizontal_deg,
|
|
)
|