This commit is contained in:
Yousef Rafat 2025-07-18 00:29:06 +03:00
parent db06eebbd8
commit 170c3e0352
2 changed files with 1 additions and 297 deletions

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@ -1,295 +0,0 @@
import torch
import torch.nn as nn
import numpy as np
from PIL import Image
import torch.nn.functional as F
def to_tensor(image_pt):
image_pt = image_pt / 255 * 2 - 1
return image_pt
def resize_nearest(img: torch.Tensor, size: int) -> torch.Tensor:
batched = (img.ndim == 4)
if img.ndim == 3:
img = img.unsqueeze(0)
img = img.permute(0, 3, 1, 2)
out = F.interpolate(img, size=size, mode='nearest')
if not batched:
out = out.squeeze(0)
return out
def cubic_kernel(x, a: float = -0.75):
absx = x.abs()
absx2 = absx ** 2
absx3 = absx ** 3
w = (a + 2) * absx3 - (a + 3) * absx2 + 1
w2 = a * absx3 - 5*a * absx2 + 8*a * absx - 4*a
return torch.where(absx <= 1, w, torch.where(absx < 2, w2, torch.zeros_like(x)))
def get_indices_weights(in_size, out_size, scale):
# OpenCV-style half-pixel mapping
x = torch.arange(out_size, dtype=torch.float32)
x = (x + 0.5) / scale - 0.5
x0 = x.floor().long()
dx = x.unsqueeze(1) - (x0.unsqueeze(1) + torch.arange(-1, 3))
weights = cubic_kernel(dx)
weights = weights / weights.sum(dim=1, keepdim=True)
indices = x0.unsqueeze(1) + torch.arange(-1, 3)
indices = indices.clamp(0, in_size - 1)
return indices, weights
def resize_cubic_1d(x, out_size, dim):
b, c, h, w = x.shape
in_size = h if dim == 2 else w
scale = out_size / in_size
indices, weights = get_indices_weights(in_size, out_size, scale)
if dim == 2:
x = x.permute(0, 1, 3, 2)
x = x.reshape(-1, h)
else:
x = x.reshape(-1, w)
gathered = x[:, indices]
out = (gathered * weights.unsqueeze(0)).sum(dim=2)
if dim == 2:
out = out.reshape(b, c, w, out_size).permute(0, 1, 3, 2)
else:
out = out.reshape(b, c, h, out_size)
return out
def resize_cubic(img: torch.Tensor, size: tuple) -> torch.Tensor:
"""
Resize image using OpenCV-equivalent INTER_CUBIC interpolation.
Implemented in pure PyTorch
"""
if img.ndim == 3:
img = img.unsqueeze(0)
img = img.permute(0, 3, 1, 2)
out_h, out_w = size
img = resize_cubic_1d(img, out_h, dim=2)
img = resize_cubic_1d(img, out_w, dim=3)
return img
def resize_area(img: torch.Tensor, size: tuple) -> torch.Tensor:
# vectorized implementation for OpenCV's INTER_AREA using pure PyTorch
original_shape = img.shape
is_hwc = False
if img.ndim == 3:
if img.shape[0] <= 4:
img = img.unsqueeze(0)
else:
is_hwc = True
img = img.permute(2, 0, 1).unsqueeze(0)
elif img.ndim == 4:
pass
else:
raise ValueError("Expected image with 3 or 4 dims.")
B, C, H, W = img.shape
out_h, out_w = size
scale_y = H / out_h
scale_x = W / out_w
device = img.device
# compute the grid boundries
y_start = torch.arange(out_h, device=device).float() * scale_y
y_end = y_start + scale_y
x_start = torch.arange(out_w, device=device).float() * scale_x
x_end = x_start + scale_x
# for each output pixel, we will compute the range for it
y_start_int = torch.floor(y_start).long()
y_end_int = torch.ceil(y_end).long()
x_start_int = torch.floor(x_start).long()
x_end_int = torch.ceil(x_end).long()
# We will build the weighted sums by iterating over contributing input pixels once
output = torch.zeros((B, C, out_h, out_w), dtype=torch.float32, device=device)
area = torch.zeros((out_h, out_w), dtype=torch.float32, device=device)
max_kernel_h = int(torch.max(y_end_int - y_start_int).item())
max_kernel_w = int(torch.max(x_end_int - x_start_int).item())
for dy in range(max_kernel_h):
for dx in range(max_kernel_w):
# compute the weights for this offset for all output pixels
y_idx = y_start_int.unsqueeze(1) + dy
x_idx = x_start_int.unsqueeze(0) + dx
# clamp indices to image boundaries
y_idx_clamped = torch.clamp(y_idx, 0, H - 1)
x_idx_clamped = torch.clamp(x_idx, 0, W - 1)
# compute weights by broadcasting
y_weight = (torch.min(y_end.unsqueeze(1), y_idx_clamped.float() + 1.0) - torch.max(y_start.unsqueeze(1), y_idx_clamped.float())).clamp(min=0)
x_weight = (torch.min(x_end.unsqueeze(0), x_idx_clamped.float() + 1.0) - torch.max(x_start.unsqueeze(0), x_idx_clamped.float())).clamp(min=0)
weight = (y_weight * x_weight)
y_expand = y_idx_clamped.expand(out_h, out_w)
x_expand = x_idx_clamped.expand(out_h, out_w)
pixels = img[:, :, y_expand, x_expand]
# unsqueeze to broadcast
w = weight.unsqueeze(0).unsqueeze(0)
output += pixels * w
area += weight
# Normalize by area
output /= area.unsqueeze(0).unsqueeze(0)
if is_hwc:
return output[0].permute(1, 2, 0)
elif img.shape[0] == 1 and original_shape[0] <= 4:
return output[0]
else:
return output
class ImageProcessorV2(nn.Module):
def __init__(self, size: int = 512, border_ratio: float = None):
super().__init__()
self.size = size
self.border_ratio = border_ratio
def load_image(self, pic, border_ratio: float = 0.15) -> torch.Tensor:
if isinstance(pic, str):
img = Image.open(pic)
img = np.array(img)
elif isinstance(pic, Image.Image):
img = np.array(pic)
if img.ndim == 2: # grayscale
img = img[:, :, None]
img = torch.from_numpy(img)
img, mask = self.recenter(img, border_ratio = border_ratio)
img = resize_cubic(img, size = (self.size, self.size))
mask = resize_nearest(mask.float(), size = self.size)
mask = mask[..., torch.newaxis]
img = to_tensor(img)
mask = to_tensor(mask)
mask = mask.permute(0, 3, 1, 2)
return img, mask
@staticmethod
def recenter(image, border_ratio: float = 0.2):
if image.shape[-1] == 4:
mask = image[..., 3]
else:
mask = torch.ones_like(image[..., 0:1]) * 255
image = torch.concatenate([image, mask], axis=-1)
mask = mask[..., 0]
H, W, C = image.shape
size = max(H, W)
result = torch.zeros((size, size, C), dtype = torch.uint8)
# as_tuple to match numpy behaviour
x_coords, y_coords = torch.nonzero(mask, as_tuple=True)
y_min, y_max = y_coords.min(), y_coords.max()
x_min, x_max = x_coords.min(), x_coords.max()
h = x_max - x_min
w = y_max - y_min
if h == 0 or w == 0:
raise ValueError('input image is empty')
desired_size = int(size * (1 - border_ratio))
scale = desired_size / max(h, w)
h2 = int(h * scale)
w2 = int(w * scale)
x2_min = (size - h2) // 2
x2_max = x2_min + h2
y2_min = (size - w2) // 2
y2_max = y2_min + w2
# note: opencv takes columns first (opposite to pytorch and numpy that take the row first)
result[x2_min:x2_max, y2_min:y2_max] = resize_area(image[x_min:x_max, y_min:y_max], (h2, w2))
bg = torch.ones((result.shape[0], result.shape[1], 3), dtype = torch.uint8) * 255
mask = result[..., 3:].to(torch.float32) / 255
result = result[..., :3] * mask + bg * (1 - mask)
mask = mask * 255
result = result.clip(0, 255).to(torch.uint8)
mask = mask.clip(0, 255).to(torch.uint8)
return result, mask
def __call__(self, image, border_ratio = 0.15, **kwargs):
if self.border_ratio is not None:
border_ratio = self.border_ratio
image, mask = self.load_image(image, border_ratio = border_ratio)
outputs = {
'image': image,
'mask': mask
}
return outputs
def test_image_processor():
"""
implementation speed: 0.24465346336364746
reference speed: 2.046062469482422
atol = 4e-2: True
"""
import time
import matplotlib.pyplot as plt
image_processor = ImageProcessorV2(size = 224)
start = time.time()
outputs = image_processor(image = r"C:\Users\yrafa\Work\Hunyuan 3D\cat.jpg")
print(time.time() - start)
image = outputs["image"]
print(image.shape)
plt.imshow(image.squeeze().permute(1, 2, 0).numpy())
plt.axis("off")
plt.show()

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@ -27,5 +27,4 @@ spandrel
soundfile
av>=14.2.0
pydantic~=2.0
pydantic-settings~=2.0
scikit-image # for 3D mesh generation (marching cubes)
pydantic-settings~=2.0