File size: 3,180 Bytes
a84fca7 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 | #!/usr/bin/env python3
"""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 # header done; skip the motion rows
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"]))
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