efast-phenocam-validation/metrics_stats.py
Felix Delattre 94f910d978 foo
2026-04-20 08:55:35 +02:00

552 lines
18 KiB
Python

"""Metrics and statistics: temporal/spatial metrics and PhenoCam stats."""
import json
import numpy as np
from pathlib import Path
from datetime import datetime, timedelta
from scipy import sparse
from scipy.sparse.linalg import spsolve
from scipy.stats import pearsonr
import rasterio
from rasterio.warp import transform as transform_coords
from metrics_indices import BLUE_BAND, GREEN_BAND, RED_BAND
WHITTAKER_LAMBDA_DAYS_SQ = 400.0
def _norm_date_key(s):
if s is None:
return None
t = str(s).strip()
return t.split("T")[0][:10] if "T" in t else t[:10]
def load_timeseries(filepath):
"""Load JSON timeseries and return dict mapping date -> value."""
if not Path(filepath).exists():
return {}
with open(filepath) as f:
data = json.load(f)
return {item["date"]: item.get("greenness_index") for item in data}
def match_dates(fusion_ts, phenocam_ts):
"""Match dates between timeseries, return aligned numpy arrays (filter None values)."""
def _bundle(m):
out = {}
for k, v in m.items():
nk = _norm_date_key(k)
if nk and nk not in out:
out[nk] = v
return out
fa, pa = _bundle(fusion_ts), _bundle(phenocam_ts)
common_dates = set(fa) & set(pa)
fusion_vals = []
phenocam_vals = []
dates = []
for date in sorted(common_dates):
fusion_val = fa[date]
phenocam_val = pa[date]
if fusion_val is not None and phenocam_val is not None:
fusion_vals.append(fusion_val)
phenocam_vals.append(phenocam_val)
dates.append(date)
return np.array(fusion_vals), np.array(phenocam_vals), dates
def pearson_correlation(y_true, y_pred):
"""Calculate Pearson correlation coefficient r."""
if len(y_true) < 2 or np.std(y_true) == 0 or np.std(y_pred) == 0:
return None
r, _ = pearsonr(y_true, y_pred)
return float(r)
def r_squared(y_true, y_pred):
"""Calculate coefficient of determination R²."""
if len(y_true) < 2 or np.std(y_true) == 0:
return None
ss_res = np.sum((y_true - y_pred) ** 2)
ss_tot = np.sum((y_true - np.mean(y_true)) ** 2)
if ss_tot == 0:
return None
return float(1 - (ss_res / ss_tot))
def rmse(y_true, y_pred):
"""Calculate Root Mean Square Error."""
if len(y_true) == 0:
return None
return float(np.sqrt(np.mean((y_true - y_pred) ** 2)))
def mae(y_true, y_pred):
"""Calculate Mean Absolute Error."""
if len(y_true) == 0:
return None
return float(np.mean(np.abs(y_true - y_pred)))
def nrmse(y_true, y_pred):
"""Calculate normalized RMSE (RMSE / mean(y_true))."""
if len(y_true) == 0:
return None
mean_val = np.mean(y_true)
if mean_val == 0:
return None
rmse_val = rmse(y_true, y_pred)
return float(rmse_val / mean_val) if rmse_val is not None else None
def nse(y_true, y_pred):
"""Calculate Nash-Sutcliffe Efficiency."""
if len(y_true) < 2:
return None
numerator = np.sum((y_true - y_pred) ** 2)
denominator = np.sum((y_true - np.mean(y_true)) ** 2)
if denominator == 0:
return None
return float(1 - (numerator / denominator))
def calculate_temporal_metrics(fusion_ts, phenocam_ts):
"""Temporal metrics vs PhenoCam (nse_pc; nse is the same value)."""
fusion_vals, phenocam_vals, dates = match_dates(fusion_ts, phenocam_ts)
if len(fusion_vals) < 2:
return None
n_pc = nse(phenocam_vals, fusion_vals)
metrics = {
"pearson_r": pearson_correlation(phenocam_vals, fusion_vals),
"r_squared": r_squared(phenocam_vals, fusion_vals),
"rmse": rmse(phenocam_vals, fusion_vals),
"mae": mae(phenocam_vals, fusion_vals),
"nrmse": nrmse(phenocam_vals, fusion_vals),
"nse_pc": n_pc,
"nse": n_pc,
"n_samples": len(fusion_vals),
"date_range": {"start": dates[0], "end": dates[-1]} if dates else None,
}
return metrics
def calculate_phenocam_stats(phenocam_ts):
"""Calculate phenocam summary statistics."""
values = [v for v in phenocam_ts.values() if v is not None]
if len(values) == 0:
return None
vals = np.array(values)
return {
"mean": float(np.mean(vals)),
"std": float(np.std(vals)),
"min": float(np.min(vals)),
"max": float(np.max(vals)),
"n_samples": len(vals),
}
def _s2_kept_date_set(base: Path, strategy: str) -> set:
path = base / "raw" / "preselection" / "s2_preselection.json"
if not path.exists():
return set()
with open(path) as f:
rows = json.load(f)
key = f"excluded_{strategy}"
out = set()
for e in rows:
if e.get(key):
continue
nk = _norm_date_key(e.get("date"))
if nk:
out.add(nk)
return out
def _whittaker_smooth_dict(obs_dates, obs_values, lam: float, n_min: int = 3):
"""Daily Whittaker (weights 1 at obs); returns {YYYY-MM-DD: z}."""
pairs = [
(_norm_date_key(d), float(v))
for d, v in zip(obs_dates, obs_values)
if v is not None and _norm_date_key(d)
]
if len(pairs) < 2:
return {}
days = sorted({p[0] for p in pairs})
t0 = datetime.strptime(days[0], "%Y-%m-%d").date()
t1 = datetime.strptime(days[-1], "%Y-%m-%d").date()
n = (t1 - t0).days + 1
if n < n_min:
return {}
w = np.zeros(n)
y = np.zeros(n)
for dk, val in pairs:
i = (datetime.strptime(dk, "%Y-%m-%d").date() - t0).days
if 0 <= i < n:
w[i] = 1.0
y[i] = val
D = sparse.diags(
[1.0, -2.0, 1.0], [0, 1, 2], shape=(n - 2, n), format="csc", dtype=np.float64
)
H = D.T @ D
Wm = sparse.diags(w.astype(np.float64), format="csc")
z = spsolve(Wm + lam * H, w * y)
out = {}
for i in range(n):
out[(t0 + timedelta(days=i)).isoformat()] = float(z[i])
return out
def _get_spatial_stats_from_raster(raster_file, site_position):
"""Extract spatial statistics (mean, std, min, max) from GCC raster in 3x3 window."""
try:
with rasterio.open(raster_file) as src:
if src.count == 1:
g = src.read(1).astype(np.float32)
lon, lat = site_position[1], site_position[0]
x, y = transform_coords("EPSG:4326", src.crs, [lon], [lat])
if not (
src.bounds.left <= x[0] <= src.bounds.right
and src.bounds.bottom <= y[0] <= src.bounds.top
):
return None
row, col = src.index(x[0], y[0])
if row < 0 or row >= src.height or col < 0 or col >= src.width:
return None
r0, r1 = max(0, row - 1), min(src.height, row + 2)
c0, c1 = max(0, col - 1), min(src.width, col + 2)
win = g[r0:r1, c0:c1]
mask = np.isfinite(win) & (win > 0)
if not np.any(mask):
return None
valid = win[mask]
return {
"mean": float(np.mean(valid)),
"std": float(np.std(valid)),
"min": float(np.min(valid)),
"max": float(np.max(valid)),
}
if src.count < 3:
return None
blue = src.read(BLUE_BAND).astype(np.float32)
green = src.read(GREEN_BAND).astype(np.float32)
red = src.read(RED_BAND).astype(np.float32)
lon, lat = site_position[1], site_position[0]
x, y = transform_coords("EPSG:4326", src.crs, [lon], [lat])
if not (
src.bounds.left <= x[0] <= src.bounds.right
and src.bounds.bottom <= y[0] <= src.bounds.top
):
return None
row, col = src.index(x[0], y[0])
if row < 0 or row >= src.height or col < 0 or col >= src.width:
return None
# Extract 3x3 window with boundary handling
r0, r1 = max(0, row - 1), min(src.height, row + 2)
c0, c1 = max(0, col - 1), min(src.width, col + 2)
blue_window = blue[r0:r1, c0:c1]
green_window = green[r0:r1, c0:c1]
red_window = red[r0:r1, c0:c1]
# Calculate GCC for each pixel in window
total = red_window + green_window + blue_window
mask = (
(total > 0)
& ~np.isnan(total)
& (blue_window >= 0)
& (green_window >= 0)
& (red_window >= 0)
)
if not np.any(mask):
return None
gcc_window = np.zeros_like(green_window, dtype=np.float32)
gcc_window[mask] = green_window[mask] / total[mask]
valid_gcc = gcc_window[mask]
if len(valid_gcc) == 0:
return None
return {
"mean": float(np.mean(valid_gcc)),
"std": float(np.std(valid_gcc)),
"min": float(np.min(valid_gcc)),
"max": float(np.max(valid_gcc)),
}
except Exception:
return None
def calculate_spatial_metrics(fusion_raster_dir, phenocam_ts, site_position):
"""Calculate r and R² on spatial statistics."""
fusion_raster_dir = Path(fusion_raster_dir)
if not fusion_raster_dir.exists():
return None
spatial_means = []
phenocam_vals = []
# Process each fusion raster file
for raster_file in sorted(fusion_raster_dir.glob("*.geotiff")):
if "DIST_CLOUD" in raster_file.name:
continue
# Extract date from filename
parts = raster_file.stem.split("_")
date_str = None
for part in parts:
if len(part) == 8 and part.isdigit():
date_str = part
break
if not date_str:
continue
# Convert to ISO format for matching
try:
date = datetime.strptime(date_str, "%Y%m%d").isoformat()
except ValueError:
continue
# Get phenocam value for this date
phenocam_val = phenocam_ts.get(date)
if phenocam_val is None:
continue
# Extract spatial statistics
stats = _get_spatial_stats_from_raster(raster_file, site_position)
if stats is None:
continue
spatial_means.append(stats["mean"])
phenocam_vals.append(phenocam_val)
if len(spatial_means) < 2:
return None
spatial_means = np.array(spatial_means)
phenocam_vals = np.array(phenocam_vals)
return {
"pearson_r": pearson_correlation(phenocam_vals, spatial_means),
"r_squared": r_squared(phenocam_vals, spatial_means),
"n_samples": len(spatial_means),
}
def calculate_scenario_metrics(season, site_name, strategy, sigma, site_position):
"""Calculate metrics for one scenario."""
base = Path(f"data/{site_name}/{season}")
processed_dir = f"processed_{strategy}_sigma{sigma}"
# Load timeseries
fusion_ts_path = base / processed_dir / "gcc" / "fusion" / "timeseries.json"
phenocam_ts_path = base / "raw" / "phenocam" / "phenocam_gcc.json"
fusion_ts = load_timeseries(fusion_ts_path)
phenocam_ts = load_timeseries(phenocam_ts_path)
if not fusion_ts or not phenocam_ts:
return None, None
# Calculate temporal metrics
temporal_metrics = calculate_temporal_metrics(fusion_ts, phenocam_ts)
# Calculate spatial metrics
fusion_raster_dir = base / processed_dir / "fusion"
spatial_metrics = calculate_spatial_metrics(
fusion_raster_dir, phenocam_ts, site_position
)
return temporal_metrics, spatial_metrics
def calculate_all_metrics(season, site_name, site_position):
"""Calculate metrics for all 4 scenarios and save to JSON."""
results = {"temporal": {}, "spatial": {}}
base = Path(f"data/{site_name}/{season}")
# Load phenocam timeseries once (same for all scenarios)
phenocam_ts_path = base / "raw" / "phenocam" / "phenocam_gcc.json"
phenocam_ts = load_timeseries(phenocam_ts_path)
if not phenocam_ts:
print("[METRICS] Warning: No phenocam data found")
return results
# Calculate phenocam stats
phenocam_stats = calculate_phenocam_stats(phenocam_ts)
if phenocam_stats:
results["phenocam_stats"] = phenocam_stats
baseline = {}
s2_ts = {}
for sub in ("processed_aggressive_sigma20", "processed_nonaggressive_sigma20"):
p = base / sub / "gcc" / "s2" / "timeseries.json"
if p.exists():
s2_ts = load_timeseries(p)
if s2_ts:
break
if s2_ts:
m0 = calculate_temporal_metrics(s2_ts, phenocam_ts)
if m0:
baseline["s2"] = m0
for strategy in ("aggressive", "nonaggressive"):
kept = _s2_kept_date_set(base, strategy)
filtered = [
(k, v)
for k, v in sorted(
s2_ts.items(), key=lambda x: _norm_date_key(x[0]) or ""
)
if _norm_date_key(k) in kept and v is not None
]
if not filtered:
continue
sub_ts = dict(filtered)
mcf = calculate_temporal_metrics(sub_ts, phenocam_ts)
if mcf:
baseline.setdefault("s2_cloudfree", {})[strategy] = mcf
obs_d, obs_v = zip(*filtered)
smooth = _whittaker_smooth_dict(obs_d, obs_v, WHITTAKER_LAMBDA_DAYS_SQ)
if smooth:
mw = calculate_temporal_metrics(smooth, phenocam_ts)
if mw:
baseline.setdefault("s2_whittaker_lambda400", {})[strategy] = mw
for strategy in ("aggressive", "nonaggressive"):
p = base / f"processed_{strategy}_sigma20" / "gcc" / "s3" / "timeseries.json"
if not p.exists():
continue
s3_ts = load_timeseries(p)
if s3_ts:
m3 = calculate_temporal_metrics(s3_ts, phenocam_ts)
if m3:
baseline.setdefault("s3", {})[strategy] = m3
if baseline:
results["baseline"] = baseline
# Calculate fusion metrics for each scenario
for strategy in ["aggressive", "nonaggressive"]:
for sigma in [20, 30]:
scenario_name = f"{strategy}_sigma{sigma}"
print(f"[METRICS] Calculating metrics for {scenario_name}...")
processed_dir = f"processed_{strategy}_sigma{sigma}"
# Load fusion timeseries
fusion_ts_path = base / processed_dir / "gcc" / "fusion" / "timeseries.json"
fusion_ts = load_timeseries(fusion_ts_path)
if not fusion_ts:
print(
f"[METRICS] Warning: Missing fusion data for {scenario_name}, skipping"
)
continue
# Calculate temporal metrics
temporal_metrics = calculate_temporal_metrics(fusion_ts, phenocam_ts)
if temporal_metrics:
results["temporal"][scenario_name] = temporal_metrics
# Calculate spatial metrics
fusion_raster_dir = base / processed_dir / "fusion"
spatial_metrics = calculate_spatial_metrics(
fusion_raster_dir, phenocam_ts, site_position
)
if spatial_metrics:
results["spatial"][scenario_name] = spatial_metrics
for strategy in ["aggressive", "nonaggressive"]:
for sigma in [20, 30]:
scenario_name = f"{strategy}_sigma{sigma}_itb"
processed_dir = f"processed_{strategy}_itb_sigma{sigma}"
fusion_ts_path = base / processed_dir / "gcc" / "fusion" / "timeseries.json"
fusion_ts = load_timeseries(fusion_ts_path)
if not fusion_ts:
print(
f"[METRICS] Warning: Missing ItB fusion data for {scenario_name}, skipping"
)
continue
temporal_metrics = calculate_temporal_metrics(fusion_ts, phenocam_ts)
if temporal_metrics:
results["temporal"][scenario_name] = temporal_metrics
fusion_raster_dir = base / processed_dir / "fusion"
spatial_metrics = calculate_spatial_metrics(
fusion_raster_dir, phenocam_ts, site_position
)
if spatial_metrics:
results["spatial"][scenario_name] = spatial_metrics
# Add summary (primary: NSE vs PhenoCam; R² kept for comparison)
if results["temporal"]:
ti = list(results["temporal"].items())
def _score(k):
return lambda x: x[1].get(k) if x[1].get(k) is not None else float("-inf")
results["summary"] = {
"best_temporal_scenario": max(ti, key=_score("nse_pc"))[0],
"best_temporal_scenario_by_r2": max(ti, key=_score("r_squared"))[0],
}
if results["spatial"]:
best_spatial = max(
results["spatial"].items(),
key=lambda x: x[1].get("r_squared", -1)
if x[1].get("r_squared") is not None
else -1,
)
if "summary" not in results:
results["summary"] = {}
results["summary"]["best_spatial_scenario"] = best_spatial[0]
# Save results
output_path = Path(f"data/{site_name}/{season}/metrics.json")
output_path.parent.mkdir(parents=True, exist_ok=True)
with open(output_path, "w") as f:
json.dump(results, f, indent=2)
print(f"[METRICS] Saved results to {output_path}")
return results
def main():
"""Standalone script entry point."""
import sys
if len(sys.argv) < 4:
print("Usage: metrics_stats.py <season> <site_name> <lat> <lon>")
print("Example: metrics_stats.py 2024 innsbruck 47.116171 11.320308")
sys.exit(1)
season = int(sys.argv[1])
site_name = sys.argv[2]
site_position = (float(sys.argv[3]), float(sys.argv[4]))
results = calculate_all_metrics(season, site_name, site_position)
# Save results
output_path = Path(f"data/{site_name}/{season}/metrics.json")
output_path.parent.mkdir(parents=True, exist_ok=True)
with open(output_path, "w") as f:
json.dump(results, f, indent=2)
print(f"[METRICS] Saved results to {output_path}")
if __name__ == "__main__":
main()