Datasets:
File size: 3,015 Bytes
12b5ac7 | 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 78 79 80 81 82 | #!/usr/bin/env python3
"""Count animation frames in a binary FBX (Kaydara 7.x).
Parses the node tree, reads AnimationCurve KeyTime arrays; frames = max key count.
Also reports the AnimationStack time span as a cross-check."""
import struct, zlib, sys
FBX_KTIME = 46186158000 # ktime units per second
def parse(path):
d = open(path, "rb").read()
assert d[:21] == b"Kaydara FBX Binary \x00", "not a binary FBX"
version = struct.unpack("<I", d[23:27])[0]
u64 = version >= 7500
pos = 27
keytime_lens = []
stack_span = [0]
def read_prop(p):
t = chr(d[p]); p += 1
if t in "YCIFDL":
sz = {"Y":2,"C":1,"I":4,"F":4,"D":8,"L":8}[t]
val = None
if t=="L": val = struct.unpack("<q", d[p:p+8])[0]
if t=="I": val = struct.unpack("<i", d[p:p+4])[0]
p += sz
return p, ("scalar", t, val)
if t in "fidlb":
length, enc, clen = struct.unpack("<III", d[p:p+12]); p += 12
raw = d[p:p+clen]; p += clen
return p, ("array", t, length)
if t in "SR":
ln = struct.unpack("<I", d[p:p+4])[0]; p += 4
s = d[p:p+ln]; p += ln
return p, ("str", t, s)
raise ValueError("bad prop type %r at %d" % (t, p))
def read_node(p):
if u64:
end, nprop, plen = struct.unpack("<QQQ", d[p:p+24]); p += 24
else:
end, nprop, plen = struct.unpack("<III", d[p:p+12]); p += 12
nl = d[p]; p += 1
name = d[p:p+nl]; p += nl
if end == 0:
return None, p # null terminator record
props = []
for _ in range(nprop):
p, pr = read_prop(p)
props.append(pr)
# KeyTime array => keyframe count
if name == b"KeyTime":
for kind,t,v in props:
if kind=="array": keytime_lens.append(v)
# AnimationStack LocalStop (int64 ktime) via Properties70 "P" records
if name == b"P" and props and props[0][2] in (b"LocalStop", b"LocalStop|LocalStop"):
for kind,t,v in props:
if kind=="scalar" and t=="L" and v: stack_span[0]=max(stack_span[0], v)
# recurse into nested nodes until `end`
while p < end - (13 if not u64 else 25):
child, p = read_node(p)
if child is None: break
p = end
return name, p
footer = len(d) - 160
while pos < footer:
node, pos = read_node(pos)
if node is None: break
return {
"version": version,
"keys_max": max(keytime_lens) if keytime_lens else 0,
"span_frames": round(stack_span[0]/FBX_KTIME*30) if stack_span[0] else 0,
}
if __name__ == "__main__":
for f in sys.argv[1:]:
try:
r = parse(f)
print("%-45s keys=%-5s span30=%-5s ver=%s" % (f.split('/')[-1], r["keys_max"], r["span_frames"], r["version"]))
except Exception as e:
print("%-45s ERR %s" % (f.split('/')[-1], e))
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