hjc-owo
init repo
966ae59
import pathlib
import random
import omegaconf
import pydiffvg
import numpy as np
import torch
from torch.optim.lr_scheduler import LambdaLR
from torchvision import transforms
from pytorch_svgrender.diffvg_warp import DiffVGState
from pytorch_svgrender.libs.modules.edge_map.DoG import XDoG
from .grad_cam import gradCAM
from . import modified_clip as clip
class Painter(DiffVGState):
def __init__(
self,
method_cfg: omegaconf.DictConfig,
diffvg_cfg: omegaconf.DictConfig,
num_strokes: int = 4,
canvas_size: int = 224,
device=None,
target_im=None,
mask=None
):
super(Painter, self).__init__(device, print_timing=diffvg_cfg.print_timing,
canvas_width=canvas_size, canvas_height=canvas_size)
self.args = method_cfg
self.num_paths = num_strokes
self.num_segments = method_cfg.num_segments
self.width = method_cfg.width
self.control_points_per_seg = method_cfg.control_points_per_seg
self.opacity_optim = method_cfg.force_sparse
self.num_stages = method_cfg.num_stages
self.noise_thresh = method_cfg.noise_thresh
self.softmax_temp = method_cfg.softmax_temp
self.color_vars_threshold = method_cfg.color_vars_threshold
self.path_svg = method_cfg.path_svg
self.strokes_per_stage = self.num_paths
self.optimize_flag = []
# attention related for strokes initialisation
self.attention_init = method_cfg.attention_init
self.saliency_model = method_cfg.saliency_model
self.xdog_intersec = method_cfg.xdog_intersec
self.mask_object = method_cfg.mask_object_attention
self.text_target = method_cfg.text_target # for clip gradients
self.saliency_clip_model = method_cfg.saliency_clip_model
self.image2clip_input = self.clip_preprocess(target_im)
self.mask = mask
self.attention_map = self.set_attention_map() if self.attention_init else None
self.thresh = self.set_attention_threshold_map() if self.attention_init else None
self.strokes_counter = 0 # counts the number of calls to "get_path"
self.epoch = 0
self.final_epoch = method_cfg.num_iter - 1
def init_image(self, stage=0):
if stage > 0:
# Noting: if multi stages training than add new strokes on existing ones
# don't optimize on previous strokes
self.optimize_flag = [False for i in range(len(self.shapes))]
for i in range(self.strokes_per_stage):
stroke_color = torch.tensor([0.0, 0.0, 0.0, 1.0])
path = self.get_path()
self.shapes.append(path)
path_group = pydiffvg.ShapeGroup(shape_ids=torch.tensor([len(self.shapes) - 1]),
fill_color=None,
stroke_color=stroke_color)
self.shape_groups.append(path_group)
self.optimize_flag.append(True)
else:
num_paths_exists = 0
if self.path_svg is not None and pathlib.Path(self.path_svg).exists():
print(f"-> init svg from `{self.path_svg}` ...")
self.canvas_width, self.canvas_height, self.shapes, self.shape_groups = self.load_svg(self.path_svg)
# if you want to add more strokes to existing ones and optimize on all of them
num_paths_exists = len(self.shapes)
for i in range(num_paths_exists, self.num_paths):
stroke_color = torch.tensor([0.0, 0.0, 0.0, 1.0])
path = self.get_path()
self.shapes.append(path)
path_group = pydiffvg.ShapeGroup(shape_ids=torch.tensor([len(self.shapes) - 1]),
fill_color=None,
stroke_color=stroke_color)
self.shape_groups.append(path_group)
self.optimize_flag = [True for i in range(len(self.shapes))]
img = self.render_warp()
img = img[:, :, 3:4] * img[:, :, :3] + torch.ones(img.shape[0], img.shape[1], 3, device=self.device) * (
1 - img[:, :, 3:4])
img = img[:, :, :3]
# Convert img from HWC to NCHW
img = img.unsqueeze(0)
img = img.permute(0, 3, 1, 2).to(self.device) # NHWC -> NCHW
return img
def get_image(self):
img = self.render_warp()
opacity = img[:, :, 3:4]
img = opacity * img[:, :, :3] + torch.ones(img.shape[0], img.shape[1], 3, device=self.device) * (1 - opacity)
img = img[:, :, :3]
# Convert img from HWC to NCHW
img = img.unsqueeze(0)
img = img.permute(0, 3, 1, 2).to(self.device) # NHWC -> NCHW
return img
def get_path(self):
points = []
self.num_control_points = torch.zeros(self.num_segments, dtype=torch.int32) + (self.control_points_per_seg - 2)
p0 = self.inds_normalised[self.strokes_counter] if self.attention_init else (random.random(), random.random())
points.append(p0)
for j in range(self.num_segments):
radius = 0.05
for k in range(self.control_points_per_seg - 1):
p1 = (p0[0] + radius * (random.random() - 0.5), p0[1] + radius * (random.random() - 0.5))
points.append(p1)
p0 = p1
points = torch.tensor(points).to(self.device)
points[:, 0] *= self.canvas_width
points[:, 1] *= self.canvas_height
path = pydiffvg.Path(num_control_points=self.num_control_points,
points=points,
stroke_width=torch.tensor(self.width),
is_closed=False)
self.strokes_counter += 1
return path
def render_warp(self):
if self.opacity_optim:
for group in self.shape_groups:
group.stroke_color.data[:3].clamp_(0., 0.) # to force black stroke
group.stroke_color.data[-1].clamp_(0., 1.) # opacity
# group.stroke_color.data[-1] = (group.stroke_color.data[-1] >= self.color_vars_threshold).float()
_render = pydiffvg.RenderFunction.apply
scene_args = pydiffvg.RenderFunction.serialize_scene(
self.canvas_width, self.canvas_height, self.shapes, self.shape_groups
)
img = _render(self.canvas_width, # width
self.canvas_height, # height
2, # num_samples_x
2, # num_samples_y
0, # seed
None,
*scene_args)
return img
def set_point_parameters(self):
self.point_vars = []
# storkes' location optimization
for i, path in enumerate(self.shapes):
if self.optimize_flag[i]:
path.points.requires_grad = True
self.point_vars.append(path.points)
def get_point_parameters(self):
return self.point_vars
def set_color_parameters(self):
# for storkes' color optimization (opacity)
self.color_vars = []
for i, group in enumerate(self.shape_groups):
if self.optimize_flag[i]:
group.stroke_color.requires_grad = True
self.color_vars.append(group.stroke_color)
def get_color_parameters(self):
return self.color_vars
def save_svg(self, output_dir: str, name: str):
pydiffvg.save_svg(f'{output_dir}/{name}.svg',
self.canvas_width, self.canvas_height, self.shapes, self.shape_groups)
def clip_preprocess(self, target_im):
model, preprocess = clip.load(self.saliency_clip_model, device=self.device, jit=False)
model.eval().to(self.device)
data_transforms = transforms.Compose([
preprocess.transforms[-1],
])
return data_transforms(target_im).to(self.device)
def clip_attn(self):
model, preprocess = clip.load(self.saliency_clip_model, device=self.device, jit=False)
model.eval().to(self.device)
if "RN" in self.saliency_clip_model:
text_input = clip.tokenize([self.text_target]).to(self.device)
saliency_layer = "layer4"
attn_map = gradCAM(
model.visual,
self.image2clip_input,
model.encode_text(text_input).float(),
getattr(model.visual, saliency_layer)
)
attn_map = attn_map.squeeze().detach().cpu().numpy()
attn_map = (attn_map - attn_map.min()) / (attn_map.max() - attn_map.min())
else: # ViT
attn_map = interpret(self.image2clip_input, model, self.device)
del model
return attn_map
def set_attention_map(self):
assert self.saliency_model in ["clip"]
if self.saliency_model == "clip":
return self.clip_attn()
def softmax(self, x, tau=0.2):
e_x = np.exp(x / tau)
return e_x / e_x.sum()
def set_inds_clip(self):
attn_map = (self.attention_map - self.attention_map.min()) / \
(self.attention_map.max() - self.attention_map.min())
if self.xdog_intersec:
xdog = XDoG(k=10)
im_xdog = xdog(self.image2clip_input[0].permute(1, 2, 0).cpu().numpy())
intersec_map = (1 - im_xdog) * attn_map
attn_map = intersec_map
attn_map_soft = np.copy(attn_map)
attn_map_soft[attn_map > 0] = self.softmax(attn_map[attn_map > 0], tau=self.softmax_temp)
k = self.num_stages * self.num_paths
self.inds = np.random.choice(range(attn_map.flatten().shape[0]), size=k, replace=False,
p=attn_map_soft.flatten())
self.inds = np.array(np.unravel_index(self.inds, attn_map.shape)).T
self.inds_normalised = np.zeros(self.inds.shape)
self.inds_normalised[:, 0] = self.inds[:, 1] / self.canvas_width
self.inds_normalised[:, 1] = self.inds[:, 0] / self.canvas_height
self.inds_normalised = self.inds_normalised.tolist()
return attn_map_soft
def set_attention_threshold_map(self):
assert self.saliency_model in ["clip"]
if self.saliency_model == "clip":
return self.set_inds_clip()
def get_attn(self):
return self.attention_map
def get_thresh(self):
return self.thresh
def get_inds(self):
return self.inds
def get_mask(self):
return self.mask
class PainterOptimizer:
def __init__(self, renderer: Painter, num_iter: int, points_lr: float, force_sparse: bool, color_lr: float):
self.renderer = renderer
self.num_iter = num_iter
self.points_lr = points_lr
self.color_lr = color_lr
self.optim_color = force_sparse
self.points_optimizer, self.color_optimizer = None, None
self.scheduler = None
def init_optimizers(self):
# optimizers
self.renderer.set_point_parameters()
self.points_optimizer = torch.optim.Adam(self.renderer.get_point_parameters(), lr=self.points_lr)
if self.optim_color:
self.renderer.set_color_parameters()
self.color_optimizer = torch.optim.Adam(self.renderer.get_color_parameters(), lr=self.color_lr)
# lr schedule
lr_lambda_fn = LinearDecayLR(self.num_iter, 0.4)
self.scheduler = LambdaLR(self.points_optimizer, lr_lambda=lr_lambda_fn, last_epoch=-1)
def update_lr(self):
self.scheduler.step()
def zero_grad_(self):
self.points_optimizer.zero_grad()
if self.optim_color:
self.color_optimizer.zero_grad()
def step_(self):
self.points_optimizer.step()
if self.optim_color:
self.color_optimizer.step()
def get_lr(self):
return self.points_optimizer.param_groups[0]['lr']
class LinearDecayLR:
def __init__(self, decay_every, decay_ratio):
self.decay_every = decay_every
self.decay_ratio = decay_ratio
def __call__(self, n):
decay_time = n // self.decay_every
decay_step = n % self.decay_every
lr_s = self.decay_ratio ** decay_time
lr_e = self.decay_ratio ** (decay_time + 1)
r = decay_step / self.decay_every
lr = lr_s * (1 - r) + lr_e * r
return lr
def interpret(image, clip_model, device):
# virtual forward to get attention map
images = image.repeat(1, 1, 1, 1)
_ = clip_model.encode_image(images) # ensure `attn_probs` in attention is not empty
clip_model.zero_grad()
image_attn_blocks = list(dict(clip_model.visual.transformer.resblocks.named_children()).values())
# create R to store attention map
num_tokens = image_attn_blocks[0].attn_probs.shape[-1]
R = torch.eye(num_tokens, num_tokens, dtype=image_attn_blocks[0].attn_probs.dtype).to(device)
R = R.unsqueeze(0).expand(1, num_tokens, num_tokens)
cams = []
for i, blk in enumerate(image_attn_blocks): # 12 attention blocks
cam = blk.attn_probs.detach() # attn_probs shape: [12, 50, 50]
# each patch is 7x7 so we have 49 pixels + 1 for positional encoding
cam = cam.reshape(1, -1, cam.shape[-1], cam.shape[-1])
cam = cam.clamp(min=0)
cam = cam.clamp(min=0).mean(dim=1) # mean of the 12 something
cams.append(cam)
R = R + torch.bmm(cam, R)
cams_avg = torch.cat(cams) # [12, 50, 50]
cams_avg = cams_avg[:, 0, 1:] # [12, 49]
image_relevance = cams_avg.mean(dim=0).unsqueeze(0) # [1, 49]
image_relevance = image_relevance.reshape(1, 1, 7, 7) # [1, 1, 7, 7]
# interpolate: [1, 1, 7, 7] -> [1, 3, 224, 224]
image_relevance = torch.nn.functional.interpolate(image_relevance, size=224, mode='bicubic')
image_relevance = image_relevance.reshape(224, 224).data.cpu().numpy().astype(np.float32)
# normalize the tensor to [0, 1]
image_relevance = (image_relevance - image_relevance.min()) / (image_relevance.max() - image_relevance.min())
return image_relevance