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260 lines
11 KiB
Python
260 lines
11 KiB
Python
"""Discover a polarity-invariant spectral carrier from low-texture groups.
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This research harness is intentionally separate from the shipping detector. It
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uses repeated, independently generated low-texture images to find Fourier bins
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whose phase is stable within a content group and whose phase axis is stable
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across groups. Treat its output as a carrier hypothesis until it passes the
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provider-oracle and hard-negative gates in the SynthID research plan.
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Usage:
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uv run --extra pixels python scripts/synthid_consensus_probe.py discover \
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refs/black refs/white refs/red --limit 5 \
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--model-out .local-eval/synthid/consensus.npz
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uv run --extra pixels python scripts/synthid_consensus_probe.py score \
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.local-eval/synthid/consensus.npz images/*.png
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"""
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from __future__ import annotations
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import json
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import logging
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from dataclasses import asdict, dataclass
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from pathlib import Path
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import click
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import numpy as np
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from PIL import Image, ImageFilter
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log = logging.getLogger(__name__)
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IMAGE_SUFFIXES = {".jpeg", ".jpg", ".png", ".webp"}
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@dataclass(frozen=True)
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class ConsensusScore:
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"""One image's alignment with a frozen carrier hypothesis."""
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path: str
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score: float
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active_weight_fraction: float
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peak_count: int
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@dataclass(frozen=True)
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class ConsensusModel:
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"""A compact, pickle-free carrier hypothesis."""
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size: int
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peaks: np.ndarray
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axial_phase: np.ndarray
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weights: np.ndarray
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expected_magnitude: np.ndarray
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def _image_paths(directory: Path, limit: int | None) -> list[Path]:
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"""Return a deterministic list of supported images in DIRECTORY."""
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paths = sorted(path for path in directory.iterdir() if path.suffix.lower() in IMAGE_SUFFIXES)
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if limit is not None:
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paths = paths[:limit]
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if not paths:
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raise ValueError(f"no supported images in {directory}")
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return paths
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def _high_pass_rgb(path: Path, size: int, blur_radius: float) -> np.ndarray:
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"""Decode PATH, canonicalize its geometry, and remove local image content."""
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with Image.open(path) as source:
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image = source.convert("RGB").resize((size, size), Image.Resampling.LANCZOS)
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pixels = np.asarray(image, dtype=np.float64)
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blurred = np.asarray(image.filter(ImageFilter.GaussianBlur(radius=blur_radius)), dtype=np.float64)
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return pixels - blurred
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def _spectrum(path: Path, size: int, blur_radius: float) -> np.ndarray:
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"""Return a centered channel-wise spectrum for PATH."""
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residual = _high_pass_rgb(path, size, blur_radius)
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return np.fft.fftshift(np.fft.fft2(residual, axes=(0, 1)), axes=(0, 1))
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def _group_statistics(paths: list[Path], size: int, blur_radius: float) -> tuple[np.ndarray, np.ndarray]:
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"""Return phase coherence and mean magnitude for one reference group."""
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spectra = [_spectrum(path, size, blur_radius) for path in paths]
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units = [spectrum / (np.abs(spectrum) + 1e-12) for spectrum in spectra]
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mean_unit = np.mean(units, axis=0)
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coherence = np.abs(mean_unit)
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mean_magnitude = np.mean([np.abs(spectrum) for spectrum in spectra], axis=0)
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phase = np.angle(mean_unit)
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return coherence * np.exp(1j * phase), mean_magnitude
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def _valid_half_plane(size: int, min_radius: float, max_radius_fraction: float) -> np.ndarray:
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"""Return the nonredundant Fourier region allowed for carrier selection."""
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center = size // 2
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yy, xx = np.ogrid[:size, :size]
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dy = yy - center
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dx = xx - center
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radius = np.sqrt(np.square(dy) + np.square(dx))
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half_plane = (dy > 0) | ((dy == 0) & (dx > 0))
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off_axis = (dy != 0) & (dx != 0)
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return half_plane & off_axis & (radius >= min_radius) & (radius <= size * max_radius_fraction)
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def discover_model(
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groups: list[list[Path]],
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*,
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size: int = 512,
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blur_radius: float = 2.0,
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peak_count: int = 256,
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min_radius: float = 8.0,
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max_radius_fraction: float = 0.4,
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) -> ConsensusModel:
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"""Discover a polarity-invariant carrier from independent image GROUPS."""
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if len(groups) < 2:
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raise ValueError("at least two reference groups are required")
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if any(len(group) < 2 for group in groups):
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raise ValueError("each reference group requires at least two images")
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group_units: list[np.ndarray] = []
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group_magnitudes: list[np.ndarray] = []
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for paths in groups:
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unit, magnitude = _group_statistics(paths, size, blur_radius)
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group_units.append(unit)
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group_magnitudes.append(magnitude)
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stacked = np.stack(group_units, axis=0)
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within_coherence = np.abs(stacked)
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group_phase = np.angle(stacked)
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axial_mean = np.mean(np.exp(2j * group_phase) * within_coherence, axis=0)
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axial_coherence = np.abs(axial_mean) / (np.mean(within_coherence, axis=0) + 1e-12)
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mean_within = np.mean(within_coherence, axis=0)
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expected_magnitude = np.mean(group_magnitudes, axis=0)
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magnitude_scale = np.median(expected_magnitude, axis=(0, 1), keepdims=True) + 1e-12
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magnitude_score = np.log1p(expected_magnitude / magnitude_scale)
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selection_score = np.square(mean_within) * np.square(axial_coherence) * magnitude_score
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selection_score *= _valid_half_plane(size, min_radius, max_radius_fraction)[:, :, None]
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candidate_count = int(np.count_nonzero(selection_score))
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if candidate_count < peak_count:
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raise ValueError(f"only {candidate_count} valid carrier candidates for {peak_count} peaks")
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flat = selection_score.ravel()
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indices = np.argpartition(flat, -peak_count)[-peak_count:]
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indices = indices[np.argsort(flat[indices])[::-1]]
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rows, columns, channels = np.unravel_index(indices, selection_score.shape)
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peaks = np.column_stack((rows - size // 2, columns - size // 2, channels)).astype(np.int32)
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axial_phase = 0.5 * np.angle(axial_mean[rows, columns, channels])
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weights = selection_score[rows, columns, channels]
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weights /= np.sum(weights)
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magnitudes = expected_magnitude[rows, columns, channels]
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return ConsensusModel(
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size=size,
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peaks=peaks,
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axial_phase=axial_phase.astype(np.float64),
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weights=weights.astype(np.float64),
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expected_magnitude=magnitudes.astype(np.float64),
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)
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def score_image(path: Path, model: ConsensusModel, *, blur_radius: float = 2.0) -> ConsensusScore:
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"""Score PATH against a frozen polarity-invariant carrier model."""
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spectrum = _spectrum(path, model.size, blur_radius)
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center = model.size // 2
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rows = center + model.peaks[:, 0]
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columns = center + model.peaks[:, 1]
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channels = model.peaks[:, 2]
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values = spectrum[rows, columns, channels]
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phase_alignment = np.cos(2.0 * (np.angle(values) - model.axial_phase))
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magnitude_gate = np.minimum(np.abs(values) / (model.expected_magnitude + 1e-12), 1.0)
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active_weights = model.weights * magnitude_gate
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active_weight = float(np.sum(active_weights))
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score = 0.0 if active_weight == 0.0 else float(np.sum(active_weights * phase_alignment) / active_weight)
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return ConsensusScore(
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path=str(path),
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score=score,
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active_weight_fraction=active_weight,
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peak_count=len(model.peaks),
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)
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def save_model(path: Path, model: ConsensusModel) -> None:
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"""Save MODEL as a pickle-free NPZ artifact."""
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path.parent.mkdir(parents=True, exist_ok=True)
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np.savez_compressed(
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path,
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size=np.asarray(model.size, dtype=np.int32),
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peaks=model.peaks.astype(np.int32),
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axial_phase=model.axial_phase.astype(np.float32),
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weights=model.weights.astype(np.float32),
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expected_magnitude=model.expected_magnitude.astype(np.float32),
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)
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def load_model(path: Path) -> ConsensusModel:
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"""Load and validate a pickle-free carrier model."""
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with np.load(path, allow_pickle=False) as artifact:
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model = ConsensusModel(
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size=int(artifact["size"]),
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peaks=np.asarray(artifact["peaks"], dtype=np.int32),
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axial_phase=np.asarray(artifact["axial_phase"], dtype=np.float64),
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weights=np.asarray(artifact["weights"], dtype=np.float64),
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expected_magnitude=np.asarray(artifact["expected_magnitude"], dtype=np.float64),
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)
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count = len(model.peaks)
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if model.peaks.ndim != 2 or model.peaks.shape[1] != 3:
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raise ValueError("invalid peak shape")
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if any(array.shape != (count,) for array in (model.axial_phase, model.weights, model.expected_magnitude)):
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raise ValueError("model arrays do not match peak count")
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if model.size < 64 or np.any(np.abs(model.peaks[:, :2]) >= model.size // 2):
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raise ValueError("invalid canonical size or peak coordinates")
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if np.any(model.peaks[:, 2] < 0) or np.any(model.peaks[:, 2] > 2):
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raise ValueError("invalid channel index")
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if not np.isclose(np.sum(model.weights), 1.0, atol=1e-5):
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raise ValueError("model weights must sum to one")
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return model
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@click.group()
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def main() -> None:
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"""Run low-texture carrier discovery and scoring experiments."""
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logging.basicConfig(level=logging.INFO, format="%(message)s")
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@main.command()
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@click.argument("group_dirs", nargs=-1, required=True, type=click.Path(exists=True, file_okay=False, path_type=Path))
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@click.option("--limit", type=click.IntRange(min=2))
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@click.option("--size", type=click.IntRange(min=64), default=512, show_default=True)
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@click.option("--peak-count", type=click.IntRange(min=1), default=256, show_default=True)
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@click.option("--model-out", type=click.Path(dir_okay=False, path_type=Path), required=True)
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def discover(group_dirs: tuple[Path, ...], limit: int | None, size: int, peak_count: int, model_out: Path) -> None:
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"""Discover a carrier from the images in each GROUP_DIRS directory."""
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groups = [_image_paths(directory, limit) for directory in group_dirs]
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model = discover_model(groups, size=size, peak_count=peak_count)
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save_model(model_out, model)
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log.info("Wrote consensus model: %s", model_out)
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@main.command()
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@click.argument("model_path", type=click.Path(exists=True, dir_okay=False, path_type=Path))
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@click.argument("images", nargs=-1, required=True, type=click.Path(exists=True, dir_okay=False, path_type=Path))
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@click.option("--report-out", type=click.Path(dir_okay=False, path_type=Path))
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def score(model_path: Path, images: tuple[Path, ...], report_out: Path | None) -> None:
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"""Score IMAGES against MODEL_PATH."""
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model = load_model(model_path)
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payload = {
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"model": str(model_path),
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"scores": [asdict(score_image(image, model)) for image in images],
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}
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rendered = json.dumps(payload, indent=2) + "\n"
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if report_out is None:
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log.info("%s", rendered.rstrip())
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return
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report_out.parent.mkdir(parents=True, exist_ok=True)
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report_out.write_text(rendered, encoding="utf-8")
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log.info("Wrote score report: %s", report_out)
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if __name__ == "__main__":
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main()
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