Download scripts/pairwise_frames.py from ibrahim80876/Change-Detection-LiDAR-Dataset: direct link, hf CLI and curl.
- Browser
- Download file 3.5 kB
-
https://huggingface.co/datasets/ibrahim80876/Change-Detection-LiDAR-Dataset/resolve/main/scripts/pairwise_frames.py
- Command line
-
hf download hf://datasets/ibrahim80876/Change-Detection-LiDAR-Dataset/scripts/pairwise_frames.py
-
curl -L -o pairwise_frames.py https://huggingface.co/datasets/ibrahim80876/Change-Detection-LiDAR-Dataset/resolve/main/scripts/pairwise_frames.py
3.5 kB
| """Every 2023 map is in its own SLAM frame and so is every 2025 loop. For each (map, loop) combination estimate the | |
| 2D rigid transform p_map = Rot(yaw) . p_loop + t by yaw-searched masked NCC of 4 m relief images. | |
| Writes pairwise_frames.json with score, ambiguity (best score at a yaw > 6 deg away), yaw, t, overlap cells.""" | |
| import numpy as np, glob, os, json, time, sys | |
| from scipy.signal import fftconvolve | |
| from multiprocessing import Pool | |
| CELL = 4.0 | |
| fps = {os.path.basename(f)[:-4]: np.load(f) for f in glob.glob('footprints/*.npz')} | |
| MAPS = sorted(k for k in fps if k.startswith('M2023')); LOOPS = sorted((k for k in fps if k.startswith('Loop')), key=lambda k: int(k[4:])) | |
| def pts(k): | |
| d = fps[k]; return d['cx'] * 2.0 + 1, d['cy'] * 2.0 + 1, np.minimum(d['zmax'] - d['zmin'], 20.0) | |
| def raster(x, y, rel, yaw=0.0): | |
| c, s = np.cos(np.radians(yaw)), np.sin(np.radians(yaw)) | |
| xr, yr = c * x - s * y, s * x + c * y | |
| ix = np.floor(xr / CELL).astype(int); iy = np.floor(yr / CELL).astype(int); ox, oy = ix.min(), iy.min(); ix -= ox; iy -= oy | |
| R = np.zeros((iy.max() + 1, ix.max() + 1)); Q = np.zeros_like(R) | |
| np.maximum.at(R, (iy, ix), rel); Q[iy, ix] = 1 | |
| return R, Q, ox, oy | |
| def mncc(R, Q, T, M, min_overlap): | |
| conv = lambda a, b: fftconvolve(a, b, mode='full') | |
| Mf = M[::-1, ::-1]; n = conv(Q, Mf); nn = np.maximum(n, 1) | |
| sR = conv(R * Q, Mf); sT = conv(Q, (T * M)[::-1, ::-1]); sRT = conv(R * Q, (T * M)[::-1, ::-1]) | |
| sRR = conv(R * R * Q, Mf); sTT = conv(Q, (T * T * M)[::-1, ::-1]) | |
| cc = (sRT - sR * sT / nn) / np.sqrt(np.maximum(sRR - sR ** 2 / nn, 1e-9) * np.maximum(sTT - sT ** 2 / nn, 1e-9)) | |
| cc[n < min_overlap] = -1 | |
| return cc, n | |
| def solve(args): | |
| m, l = args | |
| x23, y23, r23 = pts(m); x25, y25, r25 = pts(l) | |
| R, Q, ox, oy = raster(x23, y23, r23) | |
| min_ov = 700 # >= 700 cells of 4 m = 1.1 ha overlapping data | |
| res = [] | |
| for yaw in np.arange(0, 360, 3.0): | |
| T, M, tx, ty = raster(x25, y25, r25, yaw) | |
| cc, n = mncc(R, Q, T, M, min_ov) | |
| iy, ix = np.unravel_index(np.argmax(cc), cc.shape) | |
| res.append((float(cc[iy, ix]), float(yaw), int(ix), int(iy), T.shape[1], T.shape[0], tx, ty, int(n[iy, ix]))) | |
| res.sort(reverse=True) | |
| best = res[0] | |
| # refine yaw at 0.5 deg around best | |
| fine = [] | |
| for yaw in np.arange(best[1] - 3, best[1] + 3.01, 0.5): | |
| T, M, tx, ty = raster(x25, y25, r25, yaw) | |
| cc, n = mncc(R, Q, T, M, min_ov) | |
| iy, ix = np.unravel_index(np.argmax(cc), cc.shape) | |
| fine.append((float(cc[iy, ix]), float(yaw), int(ix), int(iy), T.shape[1], T.shape[0], tx, ty, int(n[iy, ix]))) | |
| fine.sort(reverse=True); sc, yaw, ix, iy, Tw, Th, tx, ty, nov = fine[0] | |
| amb = max([r[0] for r in res if min(abs(r[1] - yaw), 360 - abs(r[1] - yaw)) > 6] + [-1]) | |
| t = [float((ix - (Tw - 1) + ox - tx) * CELL), float((iy - (Th - 1) + oy - ty) * CELL)] | |
| out = {'map': m, 'loop': l, 'score': round(sc, 3), 'ambiguity': round(amb, 3), 'yaw_deg': yaw, 't': t, 'overlap_cells4m': nov, 'overlap_ha': round(nov * 16 / 1e4, 1)} | |
| print(json.dumps(out), flush=True) | |
| return out | |
| if __name__ == '__main__': | |
| combos = [(m, l) for m in MAPS for l in LOOPS] | |
| t0 = time.time() | |
| with Pool(int(sys.argv[1]) if len(sys.argv) > 1 else 6) as p: | |
| out = p.map(solve, combos, chunksize=1) | |
| json.dump(out, open('pairwise_frames.json', 'w'), indent=1) | |
| print(f'done {len(out)} combos in {time.time()-t0:.0f}s') | |