app.py

import gradio as gr
import os
import numpy as np
import trimesh as tm
from src.model import DinoV2
from src.shape_model import CSE
from PIL import Image, ImageDraw
import torch
from torchvision import transforms
import matplotlib.pyplot as plt
import hashlib

def image_hash(image):
    """Generate a hash for an image."""
    image_bytes = image.tobytes()
    hash_function = hashlib.sha256()
    hash_function.update(image_bytes)
    return hash_function.hexdigest()


#device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
device = torch.device('cpu')
models = {}
for class_name in ['bear', 'horse', 'elephant']:
    print(f'Loading model weights for {class_name}')
    models[class_name] = {
        'image_encoder': DinoV2(16),
        'cse': CSE(class_name=class_name, num_basis=64, device=device)
    }
    models[class_name]['image_encoder'].load_state_dict(torch.load(f'./models/weights/{class_name}.pth', map_location=device))
    models[class_name]['cse'].load_state_dict(torch.load(f'./models/weights/{class_name}_cse.pth', map_location=device))
    models[class_name]['cse'].functional_basis = torch.load(f'./models/weights/{class_name}_lbo.pth', map_location=device)
    
    models[class_name]['image_encoder'] = models[class_name]['image_encoder'].to(device)
    models[class_name]['cse'] = models[class_name]['cse'].to(device)
    models[class_name]['cse'].functional_basis = models[class_name]['cse'].functional_basis.to(device)
    models[class_name]['cse'].weight_matrix = models[class_name]['cse'].weight_matrix.to(device)

    models[class_name]['shape_feats'] = models[class_name]['cse']().to(device)

# Convert PIL image to a format your model expects (e.g., torch.Tensor)
transform = transforms.Compose([
    transforms.Resize((224, 224)),
    transforms.ToTensor(),
    transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
])

cached_features = {'bear': {}, 'horse': {}, 'elephant': {}}

text_description = """
# Demo for SHIC: Shape-Image Correspondences with no Keypoint Superivision (ECCV 2024)
Project website: https://www.robots.ox.ac.uk/~vgg/research/shic/

- **Step 1:** First select a class (now it defaults to 'bear') 
- **Step 2:** Upload an image of an animal from that class (or select one of the provided examples)
- **Step 3:** Click on the image (somewhere over the object) to see the image-to-shape correspondences. You can keep clicking on the input image to see new correspondences.

Notes: 
- You can click and drag to rotate the 3D shape
- Currently the demo supports bears, horses, and elephants. Other classes coming soon!
- Make sure you have selected the correct class for your image (It works cross-class too though!)
"""

example_images_dir = './gradio_example_images/'
example_images_names = [
    'bear1.png', 'bear2.png', 'bear3.png', 'winnie.png',
    'horse1.png', 'horse2.png', 'mylittlepony.png', 'ponyta.png',
    'elephant1.png', 'elephant2.png', 'dumbo.png', 'phanpy.png'
]
example_images = [os.path.join(example_images_dir, img) for img in example_images_names]
sphere_verts_ = torch.load(f'./models/weights/sphere_verts.pth', map_location=device)
sphere_faces_ = torch.load(f'./models/weights/sphere_faces.pth', map_location=device)
def center_crop(img):
    """
    Center crops an image to the target size of 224x224.
    """
    width, height = img.size   # Get dimensions
    # Calculate the target size for center cropping
    target_size = min(width, height)
    
    # Calculate the coordinates for center cropping
    left = (width - target_size) // 2
    top = (height - target_size) // 2
    right = left + target_size
    bottom = top + target_size
    
    # Perform center cropping
    cropped_img = img.crop((left, top, right, bottom))
    
    return cropped_img

def draw_point_on_image(image, x_, y_):
    """Draws a red dot on a copy of the image at the specified point."""
    # Make a copy of the image to avoid altering the original
    image_copy = image.copy()
    draw = ImageDraw.Draw(image_copy)
    x, y = x_, y_  # Adjust these based on the actual structure of `point`
    dot_radius = image.size[0] // 100
    # Draw a red dot
    draw.ellipse([(y-dot_radius, x-dot_radius), (y+dot_radius, x+dot_radius)], fill='red')
    
    return image_copy

def rotate_y(vertices, angle_degrees):
    angle_radians = np.radians(angle_degrees)
    rotation_matrix = np.array([
        [np.cos(angle_radians), 0, np.sin(angle_radians)],
        [0, 1, 0],
        [-np.sin(angle_radians), 0, np.cos(angle_radians)]
    ])
    
    # Assuming vertices is a numpy array of shape (N, 3)
    rotated_vertices = np.dot(vertices, rotation_matrix)
    return rotated_vertices

def make_final_mesh(verts, faces, similarities):
    vert_argmax = similarities.argmax(dim=1)
    vertex = verts[vert_argmax]
    color=[255, 0, 0]

    vertex_colors=similarities.transpose(1,0).cpu().detach().numpy()
    # to viridis color map
    vertex_colors = plt.cm.viridis(vertex_colors)[:, 0, :3]

    num_verts_so_far = len(verts)

    
    # Create a sphere mesh

    # Scale and translate the sphere to the desired location and size
    scale_dot = 0.015  # radius of the sphere
    translation = torch.tensor(vertex, device=device).unsqueeze(0)  # desired location

    verts_sphere = sphere_verts_ * scale_dot + translation  # scale and translate vertices
    faces_sphere = sphere_faces_ + num_verts_so_far  # faces are the same

    verts_rgb_sphere = torch.tensor([color], device=device).expand(verts_sphere.shape[0], -1)[None] / 255  # [1, N, 3]


    # verts and all sphere verts
    # concat np arrays verts + verts_sphere.cpu().numpy() (4936,3) (2562,3)
    all_verts = np.concatenate([verts, verts_sphere.cpu().numpy()], axis=0)
    all_faces = np.concatenate([faces, faces_sphere.cpu().numpy()], axis=0)

    all_textures = np.concatenate([vertex_colors, verts_rgb_sphere.cpu().numpy()[0]], axis=0)

    return tm.Trimesh(vertices=all_verts, faces=all_faces, vertex_colors=all_textures)

def process_mesh(image, class_name, x_, y_):
    x_, y_ = x_, y_
    h, w = image.size

    x = torch.tensor(x_ * 224 / w)
    y = torch.tensor(y_ * 224 / h)

    hashed_image = image_hash(image)
    if hashed_image in cached_features[class_name]:
        feats = cached_features[class_name][hashed_image]
    else:
        
        image_tensor = transform(image).unsqueeze(0)
        
        # Predict texture
        feats = models[class_name]['image_encoder'](image_tensor.to(device))

        cached_features[class_name][hashed_image] = feats

    # print('feats shape', feats.shape)

    sampled_feats = feats[:, :, x.long(), y.long()]
    similarities = torch.einsum('ik, lk -> il', sampled_feats, models[class_name]['shape_feats'])
    # normalize similarities
    similarities = (similarities - similarities.min()) / (similarities.max() - similarities.min())

    faces =  models[class_name]['cse'].shape['faces'].cpu().numpy().copy()
    verts = models[class_name]['cse'].shape['verts'].cpu().numpy().copy()

    # rotate the shape 235 
    verts = rotate_y(verts, 145)

    mesh = make_final_mesh(verts, faces, similarities)
    # save as obj
    mesh_path = './mesh.obj'
    mesh.export(mesh_path)
    
    return mesh_path

def update_output(image, class_name, evt: gr.SelectData):
    if class_name is None:
        class_name = 'bear'
    # This function will be triggered when an image is clicked.
    # evt contains the click event data, including the coordinates.
    x_, y_ = evt.index[1], evt.index[0]
    modified_image = draw_point_on_image(image, x_, y_)
    mesh_path = process_mesh(image, class_name, x_, y_)
    return modified_image, mesh_path  # Replace with the actual model path
    

with gr.Blocks() as demo:
    # choose a class
    gr.Markdown(text_description)


    with gr.Row(variant="panel"):
        with gr.Column(scale=1):
            class_name = gr.Dropdown(choices=['bear', 'horse', 'elephant'], 
                               label="Select a class (defaults to 'bear')")
            input_img = gr.Image(label="Input", type="pil", width=256)
            gr.Examples(
                examples = example_images,
                inputs = [input_img],
                cache_examples=False,
                label='Feel free to use one of our provided examples!',
                examples_per_page=30
            )
        with gr.Column(scale=1):    
            output_img = gr.Image(label="Selected Point", interactive=False, height=512)
        with gr.Column(scale=1):
            output = gr.Model3D(label='Pixel to Vertex Similarities', height=512)
    


    input_img.select(update_output, [input_img, class_name], [output_img, output])

if __name__ == "__main__":
    demo.launch(share=True)