File size: 7,689 Bytes
b6e5497 | 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 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 | """Fast BVH to MP4 renderer using PIL + ffmpeg pipe."""
import sys
import subprocess
import numpy as np
from PIL import Image, ImageDraw
WIDTH, HEIGHT = 640, 640
BG_COLOR = (0, 0, 0)
BONE_COLOR = (0, 255, 170)
JOINT_COLOR = (0, 255, 170)
JOINT_RADIUS = 3
BONE_WIDTH = 3
def parse_bvh(filepath):
with open(filepath) as f:
lines = f.readlines()
joints = []
parent_stack = []
joint_offsets = {}
joint_channels = {}
joint_parents = {}
channel_order = []
i = 0
while i < len(lines):
line = lines[i].strip()
if line.startswith('ROOT') or line.startswith('JOINT'):
name = line.split()[-1]
joints.append(name)
joint_parents[name] = parent_stack[-1] if parent_stack else None
elif line.startswith('End Site'):
name = parent_stack[-1] + '_End'
joints.append(name)
joint_parents[name] = parent_stack[-1]
elif line.startswith('OFFSET'):
vals = list(map(float, line.split()[1:]))
joint_offsets[joints[-1]] = np.array(vals)
elif line.startswith('CHANNELS'):
parts = line.split()
n_ch = int(parts[1])
ch_names = parts[2:2+n_ch]
joint_channels[joints[-1]] = ch_names
for ch in ch_names:
channel_order.append((joints[-1], ch))
elif line == '{':
if joints:
parent_stack.append(joints[-1])
elif line == '}':
if parent_stack:
parent_stack.pop()
elif line.startswith('MOTION'):
i += 1
break
i += 1
n_frames = int(lines[i].split(':')[1])
i += 1
frame_time = float(lines[i].split(':')[1])
i += 1
frames = []
while i < len(lines):
line = lines[i].strip()
if line:
frames.append(list(map(float, line.split())))
i += 1
return joints, joint_offsets, joint_channels, joint_parents, channel_order, np.array(frames), n_frames, frame_time
# Precompute rotation matrices for common angles
def rot_x(a):
c, s = np.cos(a), np.sin(a)
return np.array([[1,0,0],[0,c,-s],[0,s,c]])
def rot_y(a):
c, s = np.cos(a), np.sin(a)
return np.array([[c,0,s],[0,1,0],[-s,0,c]])
def rot_z(a):
c, s = np.cos(a), np.sin(a)
return np.array([[c,-s,0],[s,c,0],[0,0,1]])
ROT_FN = {'X': rot_x, 'Y': rot_y, 'Z': rot_z}
def compute_all_positions(frames, joints, offsets, channels, parents, ch_order):
"""Vectorized position computation for all frames."""
n_frames = len(frames)
n_joints = len(joints)
joint_idx = {j: i for i, j in enumerate(joints)}
# Build channel mapping
ch_map = {}
ci = 0
for joint, ch_name in ch_order:
if joint not in ch_map:
ch_map[joint] = {}
ch_map[joint][ch_name] = ci
ci += 1
all_positions = np.zeros((n_frames, n_joints, 3))
for fi in range(n_frames):
fd = frames[fi]
positions = {}
rotations = {}
for joint in joints:
parent = parents[joint]
offset = offsets.get(joint, np.zeros(3))
if parent is None:
cm = ch_map.get(joint, {})
tx = fd[cm['Xposition']] if 'Xposition' in cm else 0
ty = fd[cm['Yposition']] if 'Yposition' in cm else 0
tz = fd[cm['Zposition']] if 'Zposition' in cm else 0
p_pos = np.array([tx, ty, tz])
p_rot = np.eye(3)
else:
p_pos = positions[parent]
p_rot = rotations[parent]
pos = p_pos + p_rot @ offset
local_rot = np.eye(3)
if joint in channels and joint in ch_map:
for ch in channels[joint]:
if 'rotation' in ch.lower():
axis = ch[0]
val = np.radians(fd[ch_map[joint][ch]])
local_rot = local_rot @ ROT_FN[axis](val)
rotations[joint] = p_rot @ local_rot
positions[joint] = pos
all_positions[fi, joint_idx[joint]] = pos
return all_positions
def project(pos_3d, center, scale):
"""Simple orthographic projection: X right, Y up, looking from front-ish."""
# Rotate slightly for a 3/4 view
angle = np.radians(30)
c, s = np.cos(angle), np.sin(angle)
x = pos_3d[:, 0] * c + pos_3d[:, 2] * s
y = pos_3d[:, 1]
# Map to screen
sx = (x - center[0]) * scale + WIDTH / 2
sy = HEIGHT / 2 - (y - center[1]) * scale
return np.column_stack([sx, sy])
def main():
bvh_path = sys.argv[1] if len(sys.argv) > 1 else 'dance/J_Dance3_Woah/J_Dance3_Woah.bvh'
out_path = sys.argv[2] if len(sys.argv) > 2 else bvh_path.rsplit('.', 1)[0] + '.mp4'
print(f"Parsing {bvh_path}...")
joints, offsets, channels, parents, ch_order, frames, n_frames, frame_time = parse_bvh(bvh_path)
# Filter joints
finger_keywords = ['Index', 'Middle', 'Ring', 'Pinky', 'Thumb']
major_mask = [i for i, j in enumerate(joints) if '_End' not in j and not any(k in j for k in finger_keywords)]
major_joints = [joints[i] for i in major_mask]
major_set = set(major_mask)
bones = []
joint_idx = {j: i for i, j in enumerate(joints)}
for j in major_joints:
p = parents[j]
if p is not None and joint_idx[p] in major_set:
bones.append((joint_idx[p], joint_idx[j]))
# Subsample for speed
step = 2
sampled = frames[::step]
fps = 1.0 / (frame_time * step)
print(f"Computing positions for {len(sampled)} frames...")
all_pos = compute_all_positions(sampled, joints, offsets, channels, parents, ch_order)
# Compute projection params from all major joint positions
major_pos = all_pos[:, major_mask, :]
flat = major_pos.reshape(-1, 3)
angle = np.radians(30)
c, s = np.cos(angle), np.sin(angle)
proj_x = flat[:, 0] * c + flat[:, 2] * s
proj_y = flat[:, 1]
cx = (proj_x.min() + proj_x.max()) / 2
cy = (proj_y.min() + proj_y.max()) / 2
rx = (proj_x.max() - proj_x.min()) / 2
ry = (proj_y.max() - proj_y.min()) / 2
max_r = max(rx, ry) * 1.3
scale = (min(WIDTH, HEIGHT) / 2) / max_r if max_r > 0 else 1
center = np.array([cx, cy])
print(f"Rendering to {out_path} at {fps:.0f} fps...")
proc = subprocess.Popen([
'ffmpeg', '-y',
'-f', 'rawvideo', '-pix_fmt', 'rgb24',
'-s', f'{WIDTH}x{HEIGHT}',
'-r', str(int(round(fps))),
'-i', '-',
'-c:v', 'libx264', '-preset', 'fast', '-crf', '23',
'-pix_fmt', 'yuv420p',
out_path
], stdin=subprocess.PIPE, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
for fi in range(len(sampled)):
pts = project(all_pos[fi], center, scale)
img = Image.new('RGB', (WIDTH, HEIGHT), BG_COLOR)
draw = ImageDraw.Draw(img)
for pi, ci in bones:
x1, y1 = pts[pi]
x2, y2 = pts[ci]
draw.line([(x1, y1), (x2, y2)], fill=BONE_COLOR, width=BONE_WIDTH)
for idx in major_mask:
x, y = pts[idx]
draw.ellipse([x-JOINT_RADIUS, y-JOINT_RADIUS, x+JOINT_RADIUS, y+JOINT_RADIUS],
fill=JOINT_COLOR)
proc.stdin.write(np.array(img).tobytes())
proc.stdin.close()
proc.wait()
print(f"Done: {out_path}")
if __name__ == '__main__':
main()
|