neuropose/tests/unit/test_analyzer_features.py

476 lines
19 KiB
Python

"""Tests for :mod:`neuropose.analyzer.features`."""
from __future__ import annotations
import math
import numpy as np
import pytest
from neuropose.analyzer.features import (
AlignmentDiagnostics,
FeatureStatistics,
extract_feature_statistics,
extract_joint_angles,
find_peaks,
normalize_pose_sequence,
pad_sequences,
predictions_to_numpy,
procrustes_align,
)
from neuropose.io import VideoPredictions
# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------
def _make_predictions(num_frames: int, num_persons: int = 1) -> VideoPredictions:
"""Build a minimal VideoPredictions object for tests."""
frames = {}
for i in range(num_frames):
frames[f"frame_{i:06d}"] = {
"boxes": [[0.0, 0.0, 1.0, 1.0, 0.9]] * num_persons,
"poses3d": [[[float(i), float(i) * 2, float(i) * 3], [0.0, 0.0, 0.0]]] * num_persons,
"poses2d": [[[0.0, 0.0], [1.0, 1.0]]] * num_persons,
}
return VideoPredictions.model_validate(
{
"metadata": {
"frame_count": num_frames,
"fps": 30.0,
"width": 640,
"height": 480,
},
"frames": frames,
}
)
# ---------------------------------------------------------------------------
# predictions_to_numpy
# ---------------------------------------------------------------------------
class TestPredictionsToNumpy:
def test_single_person_shape(self) -> None:
predictions = _make_predictions(num_frames=4)
arr = predictions_to_numpy(predictions)
assert arr.shape == (4, 2, 3)
assert arr.dtype == np.float64
def test_values_preserved(self) -> None:
predictions = _make_predictions(num_frames=3)
arr = predictions_to_numpy(predictions)
# Frame i has joint 0 at (i, 2i, 3i) per _make_predictions.
for i in range(3):
np.testing.assert_allclose(arr[i, 0], [i, 2 * i, 3 * i])
np.testing.assert_allclose(arr[i, 1], [0, 0, 0])
def test_person_index_out_of_range(self) -> None:
predictions = _make_predictions(num_frames=2, num_persons=1)
with pytest.raises(ValueError, match="out of range"):
predictions_to_numpy(predictions, person_index=1)
def test_multi_person_with_explicit_index(self) -> None:
predictions = _make_predictions(num_frames=2, num_persons=2)
arr = predictions_to_numpy(predictions, person_index=1)
assert arr.shape == (2, 2, 3)
def test_empty_predictions_raises(self) -> None:
predictions = _make_predictions(num_frames=0)
with pytest.raises(ValueError, match="zero frames"):
predictions_to_numpy(predictions)
# ---------------------------------------------------------------------------
# normalize_pose_sequence
# ---------------------------------------------------------------------------
class TestNormalize:
def test_uniform_preserves_ratio(self) -> None:
# (frames, joints, 3) — one joint per frame, two frames.
seq = np.array(
[
[[0.0, 0.0, 0.0]],
[[3.0, 6.0, 9.0]],
]
)
# Ranges: x=3, y=6, z=9. Uniform scale = 9. All values / 9.
result = normalize_pose_sequence(seq, axis_wise=False)
np.testing.assert_allclose(result, seq / 9.0)
def test_axis_wise_each_axis_to_unit_range(self) -> None:
seq = np.array(
[
[[0.0, 0.0, 0.0]],
[[3.0, 6.0, 9.0]],
]
)
result = normalize_pose_sequence(seq, axis_wise=True)
# Per-axis normalization → each axis's max becomes 1.
np.testing.assert_allclose(result[0, 0], [0.0, 0.0, 0.0])
np.testing.assert_allclose(result[1, 0], [1.0, 1.0, 1.0])
def test_does_not_mutate_input(self) -> None:
seq = np.array([[[0.0, 0.0, 0.0]], [[1.0, 2.0, 3.0]]])
before = seq.copy()
normalize_pose_sequence(seq)
np.testing.assert_array_equal(seq, before)
def test_degenerate_sequence_rejected(self) -> None:
seq = np.zeros((3, 2, 3))
with pytest.raises(ValueError, match="degenerate"):
normalize_pose_sequence(seq)
def test_bad_shape_rejected(self) -> None:
seq = np.zeros((3, 2)) # Missing the xyz axis.
with pytest.raises(ValueError, match="expected"):
normalize_pose_sequence(seq)
def test_axis_wise_with_zero_axis_keeps_it_zero(self) -> None:
# Sequence where the Z axis never moves — axis_wise should not
# divide by zero; the Z column should remain at 0.
seq = np.array(
[
[[0.0, 0.0, 5.0]],
[[4.0, 8.0, 5.0]],
]
)
result = normalize_pose_sequence(seq, axis_wise=True)
np.testing.assert_allclose(result[:, 0, 2], [0.0, 0.0])
# ---------------------------------------------------------------------------
# pad_sequences
# ---------------------------------------------------------------------------
class TestPadSequences:
def test_pads_to_max_when_target_length_none(self) -> None:
a = np.zeros((3, 2, 3))
b = np.zeros((5, 2, 3))
padded = pad_sequences([a, b])
assert all(seq.shape[0] == 5 for seq in padded)
def test_pads_to_explicit_target_length(self) -> None:
a = np.zeros((3, 2, 3))
padded = pad_sequences([a], target_length=10)
assert padded[0].shape == (10, 2, 3)
def test_edge_padding_repeats_last_frame(self) -> None:
a = np.array([[[1.0, 2.0, 3.0]]]) # shape (1, 1, 3)
padded = pad_sequences([a], target_length=4)
# All 4 frames should equal the original single frame.
for i in range(4):
np.testing.assert_allclose(padded[0][i, 0], [1.0, 2.0, 3.0])
def test_truncates_longer_than_target(self) -> None:
a = np.zeros((10, 2, 3))
padded = pad_sequences([a], target_length=4)
assert padded[0].shape == (4, 2, 3)
def test_does_not_mutate_input(self) -> None:
a = np.zeros((3, 2, 3))
pad_sequences([a], target_length=5)
assert a.shape == (3, 2, 3)
def test_mismatched_trailing_shape_rejected(self) -> None:
a = np.zeros((3, 2, 3))
b = np.zeros((3, 4, 3)) # Different joint count.
with pytest.raises(ValueError, match="trailing shape"):
pad_sequences([a, b])
def test_empty_input_with_target(self) -> None:
assert pad_sequences([], target_length=5) == []
def test_empty_input_without_target_raises(self) -> None:
with pytest.raises(ValueError, match="empty"):
pad_sequences([])
# ---------------------------------------------------------------------------
# extract_joint_angles
# ---------------------------------------------------------------------------
class TestExtractJointAngles:
def test_right_angle(self) -> None:
# Three joints forming a right angle at joint 1.
# joint 0 at (1, 0, 0), joint 1 at origin, joint 2 at (0, 1, 0).
sequence = np.array(
[
[[1.0, 0.0, 0.0], [0.0, 0.0, 0.0], [0.0, 1.0, 0.0]],
]
)
angles = extract_joint_angles(sequence, triplets=[(0, 1, 2)])
assert angles.shape == (1, 1)
assert angles[0, 0] == pytest.approx(math.pi / 2)
def test_collinear_gives_pi(self) -> None:
sequence = np.array(
[
[[1.0, 0.0, 0.0], [0.0, 0.0, 0.0], [-1.0, 0.0, 0.0]],
]
)
angles = extract_joint_angles(sequence, triplets=[(0, 1, 2)])
assert angles[0, 0] == pytest.approx(math.pi)
def test_multiple_triplets(self) -> None:
sequence = np.array(
[
[
[1.0, 0.0, 0.0],
[0.0, 0.0, 0.0],
[0.0, 1.0, 0.0],
[0.0, 0.0, 1.0],
],
]
)
# Right angle at 1 (first triplet) and right angle at 1 again
# using joint 3 as the other arm — still 90°.
angles = extract_joint_angles(sequence, triplets=[(0, 1, 2), (0, 1, 3)])
assert angles.shape == (1, 2)
assert angles[0, 0] == pytest.approx(math.pi / 2)
assert angles[0, 1] == pytest.approx(math.pi / 2)
def test_zero_length_vector_yields_nan(self) -> None:
# Joints 0 and 1 coincide → v1 is the zero vector → NaN angle.
sequence = np.array(
[
[[0.0, 0.0, 0.0], [0.0, 0.0, 0.0], [1.0, 0.0, 0.0]],
]
)
angles = extract_joint_angles(sequence, triplets=[(0, 1, 2)])
assert math.isnan(angles[0, 0])
def test_out_of_range_index_rejected(self) -> None:
sequence = np.zeros((1, 3, 3))
with pytest.raises(ValueError, match="out of range"):
extract_joint_angles(sequence, triplets=[(0, 1, 10)])
# ---------------------------------------------------------------------------
# extract_feature_statistics
# ---------------------------------------------------------------------------
class TestExtractFeatureStatistics:
def test_basic_stats(self) -> None:
values = np.array([1.0, 2.0, 3.0, 4.0, 5.0])
stats = extract_feature_statistics(values)
assert isinstance(stats, FeatureStatistics)
assert stats.mean == pytest.approx(3.0)
assert stats.min == pytest.approx(1.0)
assert stats.max == pytest.approx(5.0)
assert stats.range == pytest.approx(4.0)
assert stats.std == pytest.approx(np.std(values))
def test_rejects_2d(self) -> None:
values = np.zeros((3, 3))
with pytest.raises(ValueError, match="1D"):
extract_feature_statistics(values)
def test_rejects_empty(self) -> None:
with pytest.raises(ValueError, match="empty"):
extract_feature_statistics(np.array([]))
# ---------------------------------------------------------------------------
# find_peaks
# ---------------------------------------------------------------------------
class TestFindPeaks:
def test_sine_wave_peaks(self) -> None:
# A sine wave over two full cycles has two peaks at quarter
# cycles — roughly at t=pi/2 and t=5pi/2 given 4pi duration.
t = np.linspace(0, 4 * np.pi, 401)
values = np.sin(t)
indices = find_peaks(values)
assert indices.ndim == 1
assert len(indices) == 2
def test_flat_signal_has_no_peaks(self) -> None:
indices = find_peaks(np.zeros(100))
assert indices.size == 0
def test_rejects_2d_input(self) -> None:
with pytest.raises(ValueError, match="1D"):
find_peaks(np.zeros((5, 5)))
# ---------------------------------------------------------------------------
# procrustes_align
# ---------------------------------------------------------------------------
def _rotation_matrix_z(angle_rad: float) -> np.ndarray:
"""Rotation matrix about the Z axis."""
c, s = np.cos(angle_rad), np.sin(angle_rad)
return np.array(
[
[c, -s, 0.0],
[s, c, 0.0],
[0.0, 0.0, 1.0],
]
)
def _skeleton(num_joints: int = 8, seed: int = 0) -> np.ndarray:
"""A deterministic, non-degenerate single-frame skeleton."""
rng = np.random.default_rng(seed)
return rng.standard_normal((num_joints, 3))
class TestProcrustesAlignPerSequence:
def test_identical_sequences_yield_identity_transform(self) -> None:
sequence = _skeleton()[np.newaxis, :, :].repeat(3, axis=0) # (3, 8, 3)
aligned, target, diag = procrustes_align(sequence, sequence, mode="per_sequence")
np.testing.assert_allclose(aligned, sequence, atol=1e-10)
np.testing.assert_array_equal(target, sequence)
assert diag.mode == "per_sequence"
assert diag.rotation_deg == pytest.approx(0.0, abs=1e-6)
assert diag.translation == pytest.approx(0.0, abs=1e-9)
assert diag.scale == pytest.approx(1.0)
def test_recovers_known_rotation(self) -> None:
# Build a reference sequence; construct the source by rotating it
# about Z, then verify alignment returns the reference up to
# floating-point error.
rotation = _rotation_matrix_z(np.deg2rad(37.0))
reference = _skeleton(num_joints=10)[np.newaxis, :, :].repeat(4, axis=0)
source = reference @ rotation.T
aligned, _, diag = procrustes_align(source, reference, mode="per_sequence")
np.testing.assert_allclose(aligned, reference, atol=1e-8)
# The recovered rotation's magnitude should be the original 37°.
assert diag.rotation_deg == pytest.approx(37.0, abs=1e-4)
def test_recovers_known_translation(self) -> None:
reference = _skeleton()[np.newaxis, :, :].repeat(5, axis=0)
translation = np.array([10.0, -4.5, 2.25])
source = reference + translation
aligned, _, diag = procrustes_align(source, reference, mode="per_sequence")
np.testing.assert_allclose(aligned, reference, atol=1e-9)
# rotation_deg may be numerically tiny but not exactly 0.
assert diag.rotation_deg == pytest.approx(0.0, abs=1e-4)
assert diag.translation == pytest.approx(np.linalg.norm(translation), rel=1e-6)
def test_recovers_combined_rotation_and_translation(self) -> None:
rotation = _rotation_matrix_z(np.deg2rad(-12.0))
translation = np.array([1.0, 2.0, 3.0])
reference = _skeleton(num_joints=6)[np.newaxis, :, :].repeat(3, axis=0)
source = reference @ rotation.T + translation
aligned, _, diag = procrustes_align(source, reference, mode="per_sequence")
np.testing.assert_allclose(aligned, reference, atol=1e-8)
assert diag.rotation_deg == pytest.approx(12.0, abs=1e-4)
assert diag.translation == pytest.approx(np.linalg.norm(translation), rel=1e-4)
def test_scale_flag_recovers_known_scale(self) -> None:
reference = _skeleton()[np.newaxis, :, :].repeat(2, axis=0)
source = reference * 0.5
aligned, _, diag = procrustes_align(source, reference, mode="per_sequence", scale=True)
np.testing.assert_allclose(aligned, reference, atol=1e-8)
assert diag.scale == pytest.approx(2.0, rel=1e-6)
def test_scale_flag_off_leaves_scale_at_one(self) -> None:
reference = _skeleton()[np.newaxis, :, :].repeat(2, axis=0)
source = reference * 0.5
_, _, diag = procrustes_align(source, reference, mode="per_sequence", scale=False)
assert diag.scale == pytest.approx(1.0)
def test_rejects_mismatched_shapes(self) -> None:
a = np.zeros((4, 8, 3))
b = np.zeros((4, 7, 3))
with pytest.raises(ValueError, match="same shape"):
procrustes_align(a, b)
def test_rejects_wrong_trailing_axis(self) -> None:
a = np.zeros((4, 8, 2))
b = np.zeros((4, 8, 2))
with pytest.raises(ValueError, match="joints, 3"):
procrustes_align(a, b)
def test_rejects_unknown_mode(self) -> None:
a = np.zeros((2, 4, 3))
with pytest.raises(ValueError, match="unknown mode"):
procrustes_align(a, a, mode="nope") # type: ignore[arg-type]
def test_does_not_mutate_inputs(self) -> None:
source = _skeleton()[np.newaxis, :, :].repeat(3, axis=0).copy()
target = (source @ _rotation_matrix_z(np.deg2rad(10.0)).T).copy()
source_before = source.copy()
target_before = target.copy()
procrustes_align(source, target, mode="per_sequence")
np.testing.assert_array_equal(source, source_before)
np.testing.assert_array_equal(target, target_before)
def test_returns_alignment_diagnostics_dataclass(self) -> None:
a = _skeleton()[np.newaxis, :, :].repeat(2, axis=0)
_, _, diag = procrustes_align(a, a)
assert isinstance(diag, AlignmentDiagnostics)
class TestProcrustesAlignPerFrame:
def test_per_frame_recovers_varying_rotations(self) -> None:
# Each frame is rotated by a different angle; per_frame alignment
# should recover each frame independently.
num_frames = 4
reference_frame = _skeleton(num_joints=6)
angles = np.deg2rad([5.0, -10.0, 20.0, 45.0])
reference = np.stack([reference_frame for _ in range(num_frames)], axis=0)
source = np.stack([reference_frame @ _rotation_matrix_z(a).T for a in angles], axis=0)
aligned, _, diag = procrustes_align(source, reference, mode="per_frame")
np.testing.assert_allclose(aligned, reference, atol=1e-8)
assert diag.mode == "per_frame"
# The max rotation across frames should be 45°.
assert diag.rotation_deg_max == pytest.approx(45.0, abs=1e-4)
# The mean rotation across frames should be 20°.
assert diag.rotation_deg == pytest.approx(20.0, abs=1e-4)
def test_per_frame_with_identical_sequences_yields_zero(self) -> None:
sequence = _skeleton(num_joints=5)[np.newaxis, :, :].repeat(3, axis=0)
aligned, _, diag = procrustes_align(sequence, sequence, mode="per_frame")
np.testing.assert_allclose(aligned, sequence, atol=1e-10)
# Per-frame SVD on a symmetric covariance is numerically ambiguous
# in axis selection, so the fitted rotation can be a few micro-
# degrees off zero; the residual positions are still exact.
assert diag.rotation_deg == pytest.approx(0.0, abs=1e-3)
assert diag.rotation_deg_max == pytest.approx(0.0, abs=1e-3)
assert diag.translation == pytest.approx(0.0, abs=1e-9)
# ---------------------------------------------------------------------------
# DTW with align= (integration)
# ---------------------------------------------------------------------------
class TestDtwAlignIntegration:
"""Smoke tests: align= routes through procrustes_align correctly.
Depth tests of the DTW path itself live in test_analyzer_dtw.
"""
def test_dtw_all_with_alignment_cancels_rigid_offset(self) -> None:
pytest.importorskip("fastdtw")
from neuropose.analyzer.dtw import dtw_all
rotation = _rotation_matrix_z(np.deg2rad(30.0))
translation = np.array([5.0, -2.0, 1.0])
reference = _skeleton(num_joints=6)[np.newaxis, :, :].repeat(4, axis=0)
source = reference @ rotation.T + translation
baseline = dtw_all(source, reference, align="none")
aligned_result = dtw_all(source, reference, align="procrustes_per_sequence")
assert baseline.distance > 0.0
assert aligned_result.distance == pytest.approx(0.0, abs=1e-6)
def test_dtw_align_rejects_mismatched_frame_counts(self) -> None:
pytest.importorskip("fastdtw")
from neuropose.analyzer.dtw import dtw_all
a = np.zeros((5, 3, 3))
b = np.zeros((6, 3, 3))
with pytest.raises(ValueError, match="matching frame counts"):
dtw_all(a, b, align="procrustes_per_sequence")