| |
| """Parse a BVH file's HIERARCHY and MOTION headers. |
| |
| Only the header is read — motion rows are skipped — so probing a whole library |
| costs almost nothing. Pass `motion=True` to also scan the rows and report whether |
| any channel actually changes: a clip can carry 91 frames that all hold the same |
| pose, and every T-pose does. |
| """ |
| import os, re, sys |
|
|
| def probe(path, motion=False): |
| joints, ends, root = [], 0, None |
| frames, frame_time = 0, 0.0 |
| depth, max_depth = 0, 0 |
| in_motion = False |
| has_motion = False |
| with open(path, "r", encoding="utf-8", errors="replace") as f: |
| for line in f: |
| s = line.strip() |
| if not in_motion: |
| if s.startswith("ROOT "): |
| root = s[5:].strip(); joints.append(root) |
| elif s.startswith("JOINT "): |
| joints.append(s[6:].strip()) |
| elif s.startswith("End Site"): |
| ends += 1 |
| elif s == "{": |
| depth += 1; max_depth = max(max_depth, depth) |
| elif s == "}": |
| depth -= 1 |
| elif s == "MOTION": |
| in_motion = True |
| else: |
| if s.startswith("Frames:"): |
| try: frames = int(s.split(":", 1)[1]) |
| except ValueError: pass |
| elif s.lower().startswith("frame time"): |
| try: frame_time = float(s.split(":", 1)[1]) |
| except ValueError: pass |
| if not motion: |
| break |
| lo = hi = None |
| for row in f: |
| try: |
| vals = [float(x) for x in row.split()] |
| except ValueError: |
| continue |
| if not vals: |
| continue |
| if lo is None: |
| lo, hi = list(vals), list(vals) |
| else: |
| n = min(len(lo), len(vals)) |
| for i in range(n): |
| if vals[i] < lo[i]: lo[i] = vals[i] |
| if vals[i] > hi[i]: hi[i] = vals[i] |
| has_motion = bool(lo) and max(h - l for l, h in zip(lo, hi)) > 1e-6 |
| break |
| fps = round(1.0 / frame_time, 3) if frame_time > 0 else 0.0 |
| out = { |
| "root": root or "", "num_joints": len(joints), "num_end_sites": ends, |
| "max_depth": max_depth, "frames": frames, |
| "frame_time": round(frame_time, 6), "fps": fps, |
| "duration_sec": round(frames * frame_time, 4) if frame_time > 0 else 0.0, |
| "joint_names": "|".join(joints)[:400], |
| } |
| if motion: |
| out["has_motion"] = has_motion |
| return out |
|
|
| if __name__ == "__main__": |
| for p in sys.argv[1:]: |
| r = probe(p) |
| print("%-34s joints=%-4d frames=%-5d fps=%-5s %.2fs root=%s" % ( |
| os.path.basename(p), r["num_joints"], r["frames"], r["fps"], |
| r["duration_sec"], r["root"])) |
|
|
