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tencentarc--pixal3d/data_toolkit/utils.py
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2026-07-13 13:16:24 +08:00

565 lines
21 KiB
Python

from typing import *
import hashlib
import numpy as np
import cv2
def get_file_hash(file: str) -> str:
sha256 = hashlib.sha256()
# Read the file from the path
with open(file, "rb") as f:
# Update the hash with the file content
for byte_block in iter(lambda: f.read(4096), b""):
sha256.update(byte_block)
return sha256.hexdigest()
# ===============LOW DISCREPANCY SEQUENCES================
PRIMES = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53]
def radical_inverse(base, n):
val = 0
inv_base = 1.0 / base
inv_base_n = inv_base
while n > 0:
digit = n % base
val += digit * inv_base_n
n //= base
inv_base_n *= inv_base
return val
def halton_sequence(dim, n):
return [radical_inverse(PRIMES[dim], n) for dim in range(dim)]
def hammersley_sequence(dim, n, num_samples):
return [n / num_samples] + halton_sequence(dim - 1, n)
def sphere_hammersley_sequence(n, num_samples, offset=(0, 0)):
u, v = hammersley_sequence(2, n, num_samples)
u += offset[0] / num_samples
v += offset[1]
u = 2 * u if u < 0.25 else 2 / 3 * u + 1 / 3
theta = np.arccos(1 - 2 * u) - np.pi / 2
phi = v * 2 * np.pi
return [phi, theta]
# ==============PLY IO===============
import struct
import re
import torch
def read_ply(filename):
"""
Read a PLY file and return vertices, triangle faces, and quad faces.
Args:
filename (str): The file path to read from.
Returns:
vertices (torch.Tensor): Tensor of shape [N, 3] containing vertex positions.
tris (torch.Tensor): Tensor of shape [M, 3] containing triangle face indices (empty if none).
quads (torch.Tensor): Tensor of shape [K, 4] containing quad face indices (empty if none).
"""
with open(filename, 'rb') as f:
# Read the header until 'end_header' is encountered
header_bytes = b""
while True:
line = f.readline()
if not line:
raise ValueError("PLY header not found")
header_bytes += line
if b"end_header" in line:
break
header = header_bytes.decode('utf-8')
# Determine if the file is in ASCII or binary format
is_ascii = "ascii" in header
# Extract the number of vertices and faces from the header using regex
vertex_match = re.search(r'element vertex (\d+)', header)
if vertex_match:
num_vertices = int(vertex_match.group(1))
else:
raise ValueError("Vertex count not found in header")
face_match = re.search(r'element face (\d+)', header)
if face_match:
num_faces = int(face_match.group(1))
else:
raise ValueError("Face count not found in header")
vertices = []
tris = []
quads = []
if is_ascii:
# For ASCII format, read each line of vertex data (each line contains 3 floats)
for _ in range(num_vertices):
line = f.readline().decode('utf-8').strip()
if not line:
continue
parts = line.split()
vertices.append([float(parts[0]), float(parts[1]), float(parts[2])])
# Read face data, where the first number indicates the number of vertices for the face
for _ in range(num_faces):
line = f.readline().decode('utf-8').strip()
if not line:
continue
parts = line.split()
count = int(parts[0])
indices = list(map(int, parts[1:]))
if count == 3:
tris.append(indices)
elif count == 4:
quads.append(indices)
else:
# Skip faces with other numbers of vertices (can be extended as needed)
pass
else:
# For binary format: read directly from the binary stream
# Each vertex consists of 3 floats (12 bytes per vertex)
for _ in range(num_vertices):
data = f.read(12)
if len(data) < 12:
raise ValueError("Insufficient vertex data")
v = struct.unpack('<fff', data)
vertices.append(v)
# Read face data from the binary stream
for _ in range(num_faces):
# First, read 1 byte indicating the number of vertices in the face
count_data = f.read(1)
if len(count_data) < 1:
raise ValueError("Failed to read face vertex count")
count = struct.unpack('<B', count_data)[0]
if count == 3:
data = f.read(12) # 3 * 4 bytes
if len(data) < 12:
raise ValueError("Insufficient data for triangle face")
indices = struct.unpack('<3i', data)
tris.append(indices)
elif count == 4:
data = f.read(16) # 4 * 4 bytes
if len(data) < 16:
raise ValueError("Insufficient data for quad face")
indices = struct.unpack('<4i', data)
quads.append(indices)
else:
# For faces with a different number of vertices, read count*4 bytes
data = f.read(count * 4)
# Skip or extend processing as needed
raise ValueError(f"Unsupported face with {count} vertices")
# Convert lists to torch.Tensor
vertices = torch.tensor(vertices, dtype=torch.float32)
tris = torch.tensor(tris, dtype=torch.int32) if len(tris) > 0 else torch.empty((0, 3), dtype=torch.int32)
quads = torch.tensor(quads, dtype=torch.int32) if len(quads) > 0 else torch.empty((0, 4), dtype=torch.int32)
return vertices, tris, quads
def write_ply(filename, vertices, tris, quads, ascii=False):
"""
Write a mesh to a PLY file, with the option to save in ASCII or binary format.
Args:
filename (str): The filename to write to.
vertices (torch.Tensor): [N, 3] The vertex positions.
tris (torch.Tensor): [M, 3] The triangle indices.
quads (torch.Tensor): [K, 4] The quad indices.
ascii (bool): If True, write in ASCII format. If False, write in binary format.
"""
# Convert torch tensors to numpy arrays
vertices = vertices.numpy()
tris = tris.numpy()
quads = quads.numpy()
# Prepare the header
num_vertices = len(vertices)
num_faces = len(tris) + len(quads)
# Vertex properties
vertex_header = "property float x\nproperty float y\nproperty float z"
# Face properties (the number of vertices per face is variable)
face_header = "property list uchar int vertex_index"
# Start writing the PLY header
header = f"ply\n"
header += f"format {'ascii 1.0' if ascii else 'binary_little_endian 1.0'}\n"
header += f"element vertex {num_vertices}\n"
header += vertex_header + "\n"
header += f"element face {num_faces}\n"
header += face_header + "\n"
header += "end_header\n"
# Open the file for writing
with open(filename, 'wb' if not ascii else 'w') as f:
# Write the header
f.write(header if ascii else header.encode('utf-8'))
# Write the vertex data
if ascii:
for v in vertices:
f.write(f"{v[0]} {v[1]} {v[2]}\n")
else:
for v in vertices:
f.write(struct.pack('<fff', *v))
# Write the face data
if ascii:
for tri in tris:
f.write(f"3 {tri[0]} {tri[1]} {tri[2]}\n")
for quad in quads:
f.write(f"4 {quad[0]} {quad[1]} {quad[2]} {quad[3]}\n")
else:
for tri in tris:
f.write(struct.pack('<B3i', 3, *tri)) # 3 indices for triangle
for quad in quads:
f.write(struct.pack('<B4i', 4, *quad)) # 4 indices for quad
# ==============IMAGE UTILS===============
def make_grid(images, nrow=None, ncol=None, aspect_ratio=None):
num_images = len(images)
if nrow is None and ncol is None:
if aspect_ratio is not None:
nrow = int(np.round(np.sqrt(num_images / aspect_ratio)))
else:
nrow = int(np.sqrt(num_images))
ncol = (num_images + nrow - 1) // nrow
elif nrow is None and ncol is not None:
nrow = (num_images + ncol - 1) // ncol
elif nrow is not None and ncol is None:
ncol = (num_images + nrow - 1) // nrow
else:
assert nrow * ncol >= num_images, 'nrow * ncol must be greater than or equal to the number of images'
if images[0].ndim == 2:
grid = np.zeros((nrow * images[0].shape[0], ncol * images[0].shape[1]), dtype=images[0].dtype)
else:
grid = np.zeros((nrow * images[0].shape[0], ncol * images[0].shape[1], images[0].shape[2]), dtype=images[0].dtype)
for i, img in enumerate(images):
row = i // ncol
col = i % ncol
grid[row * img.shape[0]:(row + 1) * img.shape[0], col * img.shape[1]:(col + 1) * img.shape[1]] = img
return grid
def notes_on_image(img, notes=None):
img = np.pad(img, ((0, 32), (0, 0), (0, 0)), 'constant', constant_values=0)
img = cv2.cvtColor(img, cv2.COLOR_RGB2BGR)
if notes is not None:
img = cv2.putText(img, notes, (0, img.shape[0] - 4), cv2.FONT_HERSHEY_SIMPLEX, 1, (255, 255, 255), 1)
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
return img
def text_image(text, resolution=(512, 512), max_size=0.5, h_align="left", v_align="center"):
"""
Draw text on an image of the given resolution. The text is automatically wrapped
and scaled so that it fits completely within the image while preserving any explicit
line breaks and original spacing. Horizontal and vertical alignment can be controlled
via flags.
Parameters:
text (str): The input text. Newline characters and spacing are preserved.
resolution (tuple): The image resolution as (width, height).
max_size (float): The maximum font size.
h_align (str): Horizontal alignment. Options: "left", "center", "right".
v_align (str): Vertical alignment. Options: "top", "center", "bottom".
Returns:
numpy.ndarray: The resulting image (BGR format) with the text drawn.
"""
width, height = resolution
# Create a white background image
img = np.full((height, width, 3), 255, dtype=np.uint8)
# Set margins and compute available drawing area
margin = 10
avail_width = width - 2 * margin
avail_height = height - 2 * margin
# Choose OpenCV font and text thickness
font = cv2.FONT_HERSHEY_SIMPLEX
thickness = 1
# Ratio for additional spacing between lines (relative to the height of "A")
line_spacing_ratio = 0.5
def wrap_line(line, max_width, font, thickness, scale):
"""
Wrap a single line of text into multiple lines such that each line's
width (measured at the given scale) does not exceed max_width.
This function preserves the original spacing by splitting the line into tokens
(words and whitespace) using a regular expression.
Parameters:
line (str): The input text line.
max_width (int): Maximum allowed width in pixels.
font (int): OpenCV font identifier.
thickness (int): Text thickness.
scale (float): The current font scale.
Returns:
List[str]: A list of wrapped lines.
"""
# Split the line into tokens (words and whitespace), preserving spacing
tokens = re.split(r'(\s+)', line)
if not tokens:
return ['']
wrapped_lines = []
current_line = ""
for token in tokens:
candidate = current_line + token
candidate_width = cv2.getTextSize(candidate, font, scale, thickness)[0][0]
if candidate_width <= max_width:
current_line = candidate
else:
# If current_line is empty, the token itself is too wide;
# break the token character by character.
if current_line == "":
sub_token = ""
for char in token:
candidate_char = sub_token + char
if cv2.getTextSize(candidate_char, font, scale, thickness)[0][0] <= max_width:
sub_token = candidate_char
else:
if sub_token:
wrapped_lines.append(sub_token)
sub_token = char
current_line = sub_token
else:
wrapped_lines.append(current_line)
current_line = token
if current_line:
wrapped_lines.append(current_line)
return wrapped_lines
def compute_text_block(scale):
"""
Wrap the entire text (splitting at explicit newline characters) using the
provided scale, and then compute the overall width and height of the text block.
Returns:
wrapped_lines (List[str]): The list of wrapped lines.
block_width (int): Maximum width among the wrapped lines.
block_height (int): Total height of the text block including spacing.
sizes (List[tuple]): A list of (width, height) for each wrapped line.
spacing (int): The spacing between lines (computed from the scaled "A" height).
"""
# Split text by explicit newlines
input_lines = text.splitlines() if text else ['']
wrapped_lines = []
for line in input_lines:
wrapped = wrap_line(line, avail_width, font, thickness, scale)
wrapped_lines.extend(wrapped)
sizes = []
for line in wrapped_lines:
(text_size, _) = cv2.getTextSize(line, font, scale, thickness)
sizes.append(text_size) # (width, height)
block_width = max((w for w, h in sizes), default=0)
# Use the height of "A" (at the current scale) to compute line spacing
base_height = cv2.getTextSize("A", font, scale, thickness)[0][1]
spacing = int(line_spacing_ratio * base_height)
block_height = sum(h for w, h in sizes) + spacing * (len(sizes) - 1) if sizes else 0
return wrapped_lines, block_width, block_height, sizes, spacing
# Use binary search to find the maximum scale that allows the text block to fit
lo = 0.001
hi = max_size
eps = 0.001 # convergence threshold
best_scale = lo
best_result = None
while hi - lo > eps:
mid = (lo + hi) / 2
wrapped_lines, block_width, block_height, sizes, spacing = compute_text_block(mid)
# Ensure that both width and height constraints are met
if block_width <= avail_width and block_height <= avail_height:
best_scale = mid
best_result = (wrapped_lines, block_width, block_height, sizes, spacing)
lo = mid # try a larger scale
else:
hi = mid # reduce the scale
if best_result is None:
best_scale = 0.5
best_result = compute_text_block(best_scale)
wrapped_lines, block_width, block_height, sizes, spacing = best_result
# Compute starting y-coordinate based on vertical alignment flag
if v_align == "top":
y_top = margin
elif v_align == "center":
y_top = margin + (avail_height - block_height) // 2
elif v_align == "bottom":
y_top = margin + (avail_height - block_height)
else:
y_top = margin + (avail_height - block_height) // 2 # default to center if invalid flag
# For cv2.putText, the y coordinate represents the text baseline;
# so for the first line add its height.
y = y_top + (sizes[0][1] if sizes else 0)
# Draw each line with horizontal alignment based on the flag
for i, line in enumerate(wrapped_lines):
line_width, line_height = sizes[i]
if h_align == "left":
x = margin
elif h_align == "center":
x = margin + (avail_width - line_width) // 2
elif h_align == "right":
x = margin + (avail_width - line_width)
else:
x = margin # default to left if invalid flag
cv2.putText(img, line, (x, y), font, best_scale, (0, 0, 0), thickness, cv2.LINE_AA)
y += line_height + spacing
return img
# ==================== View index parsing ====================
def parse_view_indices(view_indices_str):
"""Parse view_indices string into a sorted deduplicated list of integers."""
if view_indices_str is None:
return None
view_indices = []
for part in view_indices_str.split(','):
if '-' in part:
start, end = map(int, part.split('-'))
view_indices.extend(range(start, end + 1))
else:
view_indices.append(int(part))
view_indices = list(set(view_indices))
view_indices.sort()
return view_indices
# ==================== Multi-view transform functions ====================
import math
def get_new_camera_matrix(radius: float, yaw: float, pitch: float, dtype=torch.float32, device='cpu'):
"""
Compute camera-to-world 4x4 transform matrix in spherical coordinates,
looking at origin with up=(0,1,0).
Uses standard LookAt formula where camera local -Z points at target and local Y is up.
An additional +90 degree rotation around local Z axis is applied to match
Blender Track-To local axis convention.
yaw, pitch are in radians.
"""
x = radius * math.cos(yaw) * math.cos(pitch)
y = radius * math.sin(yaw) * math.cos(pitch)
z = radius * math.sin(pitch)
eye = torch.tensor([x, y, z], dtype=dtype, device=device)
target = torch.zeros(3, dtype=dtype, device=device)
up_global = torch.tensor([0.0, 1.0, 0.0], dtype=dtype, device=device)
f = (target - eye)
f = f / torch.norm(f)
r = torch.cross(f, up_global)
r = r / torch.norm(r)
u = torch.cross(r, f)
z_cam = -f
x_cam = r
y_cam = u
T = torch.eye(4, dtype=dtype, device=device)
T[:3, 0] = x_cam
T[:3, 1] = y_cam
T[:3, 2] = z_cam
T[:3, 3] = eye
# +90 degree rotation matrix around local Z axis
Rz90 = torch.tensor([
[0.0, -1.0, 0.0, 0.0],
[1.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 1.0, 0.0],
[0.0, 0.0, 0.0, 1.0]
], dtype=dtype, device=device)
return T @ Rz90
def transform_mesh(mesh_v, frame):
"""
Apply multi-view transform to mesh vertices based on camera transform matrix.
"""
device = mesh_v.device
c2w_orig = torch.tensor(frame['transform_matrix'], dtype=torch.float32, device=device)
# Old and new camera matrices
radius = c2w_orig[:3, 3].norm().item()
c2w_new = get_new_camera_matrix(radius=radius, yaw=-90/180.0*math.pi, pitch=0.0,
dtype=torch.float32, device=device)
w2c_orig = torch.inverse(c2w_orig)
# Initial and final axis alignment matrices
R_init = torch.tensor([
[1.0, 0.0, 0.0, 0.0],
[0.0, 0.0, -1.0, 0.0],
[0.0, 1.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 1.0]
], dtype=torch.float32, device=device)
R_back = torch.tensor([
[1.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 1.0, 0.0],
[0.0, -1.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 1.0]
], dtype=torch.float32, device=device)
R_ply = torch.tensor([
[1.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 1.0, 0.0],
[0.0, -1.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 1.0]
], dtype=torch.float32, device=device)
T_cam = c2w_new @ w2c_orig @ R_ply
T_final = R_back @ T_cam @ R_init
# Apply transform
mesh_v = mesh_v.reshape(-1, 3)
verts_h = torch.cat([mesh_v, torch.ones((mesh_v.shape[0], 1), dtype=torch.float32, device=device)], dim=1)
verts_trans = (T_final @ verts_h.T).T[:, :3]
return verts_trans
def sphere_normalize_torch(vertices):
"""
Sphere normalization: normalize vertices based on sphere radius.
"""
bmin = torch.min(vertices, dim=0)[0]
bmax = torch.max(vertices, dim=0)[0]
bcenter = (bmax + bmin) / 2
assert bcenter.abs().max() < 0.25, f"bcenter is not close to origin: {bcenter}"
radius = torch.norm(vertices - bcenter, dim=-1).max()
vertices_normalized = vertices / radius
return vertices_normalized, bcenter, radius
def save_image_with_notes(img, path, notes=None):
"""
Save an image with notes.
"""
if isinstance(img, torch.Tensor):
img = img.cpu().numpy().transpose(1, 2, 0)
if img.dtype == np.float32 or img.dtype == np.float64:
img = np.clip(img * 255, 0, 255).astype(np.uint8)
img = notes_on_image(img, notes)
cv2.imwrite(path, cv2.cvtColor(img, cv2.COLOR_RGB2BGR))