### Relevant imports & set up
```python
!pip install geopy > delete.txt
!pip install datasets > delete.txt
!pip install torch torchvision datasets > delete.txt
!pip install huggingface_hub > delete.txt
!rm delete.txt
```

```python
!pip install transformers
import transformers
```

```python
!huggingface-cli login --token [your_token]
```

```python
lat_mean = 39.95156937654321
lat_std = 0.0005992518588323268
lon_mean = -75.19136795987654
lon_std = 0.0007030395253318959
```

### Instructions
Our current best performing model is an ensemble of multiple models. To run it on hidden test data, first run the model definitions.

#### Load and define models

```python
from transformers import AutoModelForImageClassification, PretrainedConfig, PreTrainedModel
import torch
import torch.nn as nn
import os
from huggingface_hub import PyTorchModelHubMixin, hf_hub_download
from safetensors.torch import load_file 

class CustomConvNeXtConfig(PretrainedConfig):
    model_type = "custom-convnext"

    def __init__(self, num_labels=2, **kwargs):
        super().__init__(**kwargs)
        self.num_labels = num_labels  # Register number of labels (output dimensions)

class CustomConvNeXtModel(PreTrainedModel):
    config_class = CustomConvNeXtConfig

    def __init__(self, config, model_name="facebook/convnext-tiny-224",
                 num_classes=2, train_final_layer_only=False):
        super().__init__(config)

        # Load pre-trained ConvNeXt model from Hugging Face
        self.convnext = AutoModelForImageClassification.from_pretrained(model_name)

        # Access the input features of the existing classifier
        in_features = self.convnext.classifier.in_features

        # Modify the classifier layer to match the number of output classes
        self.convnext.classifier = nn.Linear(in_features, num_classes)

        # Freeze previous weights if only training the final layer
        if train_final_layer_only:
            for name, param in self.convnext.named_parameters():
                if "classifier" not in name:
                    param.requires_grad = False
                else:
                    print(f"Unfrozen layer: {name}")

    def forward(self, x):
        return self.convnext(x)

    @classmethod
    def from_pretrained(cls, repo_id, model_name="facebook/convnext-tiny-224", **kwargs):
        """Load model weights and configuration from Hugging Face Hub."""
        # Download model.safetensors from Hugging Face Hub
        model_path = hf_hub_download(repo_id=repo_id, filename="model.safetensors")
    
        # Download config.json from Hugging Face Hub
        config_path = hf_hub_download(repo_id=repo_id, filename="config.json")
    
        # Load configuration
        config = CustomConvNeXtConfig.from_pretrained(config_path)
    
        # Create the model
        model = cls(config=config, model_name=model_name, num_classes=config.num_labels)
    
        # Load state_dict from safetensors file
        state_dict = load_file(model_path)
        model.load_state_dict(state_dict)
    
        return model


class CustomResNetConfig(PretrainedConfig):
    model_type = "custom-resnet"

    def __init__(self, num_labels=2, **kwargs):
        super().__init__(**kwargs)
        self.num_labels = num_labels  # Register number of labels (output dimensions)

class CustomResNetModel(nn.Module, PyTorchModelHubMixin):
    config_class = CustomResNetConfig

    def __init__(self, model_name="microsoft/resnet-18",
                 num_classes=2,
                 train_final_layer_only=False):
        super().__init__()

        # Load pre-trained ResNet model from Hugging Face
        self.resnet = AutoModelForImageClassification.from_pretrained(model_name)

        # Access the Linear layer within the Sequential classifier
        in_features = self.resnet.classifier[1].in_features  # Accessing the Linear layer within the Sequential

        # Modify the classifier layer to have the desired number of output classes
        self.resnet.classifier = nn.Sequential(
            nn.Flatten(),
            nn.Linear(in_features, num_classes)
        )

        self.config = CustomResNetConfig(num_labels=num_classes)

        # Freeze previous weights
        if train_final_layer_only:
            for name, param in self.resnet.named_parameters():
                if "classifier" not in name:
                    param.requires_grad = False
                else:
                    print(f"Unfrozen layer: {name}")

    def forward(self, x):
        return self.resnet(x)

    def save_pretrained(self, save_directory, **kwargs):
        """Save model weights and custom configuration in Hugging Face format."""
        os.makedirs(save_directory, exist_ok=True)

        # Save model weights
        torch.save(self.state_dict(), os.path.join(save_directory, "pytorch_model.bin"))

        # Save configuration
        self.config.save_pretrained(save_directory)

    @classmethod
    def from_pretrained(cls, repo_id, model_name="microsoft/resnet-18", **kwargs):
        """Load model weights and configuration from Hugging Face Hub or local directory."""
        # Download pytorch_model.bin from Hugging Face Hub
        model_path = hf_hub_download(repo_id=repo_id, filename="pytorch_model.bin")

        # Download config.json from Hugging Face Hub
        config_path = hf_hub_download(repo_id=repo_id, filename="config.json")

        # Load configuration
        config = CustomResNetConfig.from_pretrained(config_path)

        # Create the model
        model = cls(model_name=model_name, num_classes=config.num_labels)

        # Load state_dict
        model.load_state_dict(torch.load(model_path, map_location=torch.device("cpu")))

        return model


class CustomEfficientNetConfig(PretrainedConfig):
    model_type = "custom-efficientnet"

    def __init__(self, num_labels=2, **kwargs):
        super().__init__(**kwargs)
        self.num_labels = num_labels  # Register number of labels (output dimensions)

class CustomEfficientNetModel(PreTrainedModel):
    config_class = CustomEfficientNetConfig

    def __init__(self, config, model_name="google/efficientnet-b0",
                 num_classes=2, train_final_layer_only=False):
        super().__init__(config)

        # Load pre-trained EfficientNet model from Hugging Face
        self.efficientnet = AutoModelForImageClassification.from_pretrained(model_name)

        # Access the input features of the existing classifier
        in_features = self.efficientnet.classifier.in_features

        # Modify the classifier layer to match the number of output classes
        self.efficientnet.classifier = nn.Sequential(
            nn.Linear(in_features, num_classes)
        )

        # Freeze previous weights if only training the final layer
        if train_final_layer_only:
            for name, param in self.efficientnet.named_parameters():
                if "classifier" not in name:
                    param.requires_grad = False
                else:
                    print(f"Unfrozen layer: {name}")

    def forward(self, x):
        return self.efficientnet(x)

    @classmethod
    def from_pretrained(cls, repo_id, model_name="google/efficientnet-b0", **kwargs):
        """Load model weights and configuration from Hugging Face Hub."""
        # Attempt to download the safetensors model file
        try:
            model_path = hf_hub_download(repo_id=repo_id, filename="model.safetensors")
            state_dict = load_file(model_path)
        except Exception as e:
            raise ValueError(
                f"Failed to download or load 'model.safetensors' from {repo_id}. Ensure the file exists."
            ) from e

        # Download config.json from Hugging Face Hub
        config_path = hf_hub_download(repo_id=repo_id, filename="config.json")

        # Load configuration
        config = CustomEfficientNetConfig.from_pretrained(config_path)

        # Create the model
        model = cls(config=config, model_name=model_name, num_classes=config.num_labels)

        # Load the state_dict into the model
        model.load_state_dict(state_dict)

        return model


class CustomViTConfig(PretrainedConfig):
    model_type = "custom-vit"

    def __init__(self, num_labels=2, **kwargs):
        super().__init__(**kwargs)
        self.num_labels = num_labels  # Register number of labels (output dimensions)

class CustomViTModel(PreTrainedModel):
    config_class = CustomViTConfig

    def __init__(self, config, model_name="google/vit-base-patch16-224",
                 num_classes=2, train_final_layer_only=False):
        super().__init__(config)

        # Load pre-trained ViT model from Hugging Face
        self.vit = AutoModelForImageClassification.from_pretrained(model_name)

        # Access the input features of the existing classifier
        in_features = self.vit.classifier.in_features

        # Modify the classifier layer to match the number of output classes
        self.vit.classifier = nn.Linear(in_features, num_classes)

        # Freeze previous weights if only training the final layer
        if train_final_layer_only:
            for name, param in self.vit.named_parameters():
                if "classifier" not in name:
                    param.requires_grad = False
                else:
                    print(f"Unfrozen layer: {name}")

    def forward(self, x):
        return self.vit(x)

    @classmethod
    def from_pretrained(cls, repo_id, model_name="google/vit-base-patch16-224", **kwargs):
        # Attempt to download the safetensors model file
        try:
            model_path = hf_hub_download(repo_id=repo_id, filename="model.safetensors")
            state_dict = load_file(model_path)
        except Exception as e:
            raise ValueError(
                f"Failed to download or load 'model.safetensors' from {repo_id}. Ensure the file exists."
            ) from e

        # Download config.json from Hugging Face Hub
        config_path = hf_hub_download(repo_id=repo_id, filename="config.json")

        # Load configuration
        config = CustomViTConfig.from_pretrained(config_path)

        # Create the model
        model = cls(config=config, model_name=model_name, num_classes=config.num_labels)

        # Load the state_dict into the model
        model.load_state_dict(state_dict)

        return model


# Define the WeightedEnsembleModel class
class WeightedEnsembleModel(nn.Module):
    def __init__(self, models, weights):
        """
        Initialize the ensemble model with individual models and their weights.
        """
        super(WeightedEnsembleModel, self).__init__()
        self.models = nn.ModuleList(models)  # Wrap models in ModuleList
        self.weights = weights

    def forward(self, images):
        """
        Forward pass for the ensemble model.
        Performs weighted averaging of logits from individual models.
        """
        ensemble_logits = torch.zeros((images.size(0), 2)).to(images.device)  # Initialize logits
        for model, weight in zip(self.models, self.weights):
            outputs = model(images)
            logits = outputs.logits if hasattr(outputs, "logits") else outputs  # Extract logits
            ensemble_logits += weight * logits  # Weighted sum of logits
        return ensemble_logits



```


Now, load the model weights from huggingface.
```python
from transformers import AutoModelForImageClassification
import torch
from sklearn.metrics import mean_absolute_error, mean_squared_error
import matplotlib.pyplot as plt
import numpy as np

device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
```

```python
#resnet
resnet = CustomResNetModel.from_pretrained(
    "final-project-5190/model-resnet-50-base",
    model_name="microsoft/resnet-50"
)

#convnext
convnext=CustomConvNeXtModel.from_pretrained(
    "final-project-5190/model-convnext-tiny-reducePlateau", 
    model_name="facebook/convnext-tiny-224")

#vit
vit = CustomViTModel.from_pretrained(
    "final-project-5190/model-ViT-base",
    model_name="google/vit-base-patch16-224"
)

#efficientnet
efficientnet = CustomEfficientNetModel.from_pretrained(
    "final-project-5190/model-efficientnet-b0-base",
    model_name="google/efficientnet-b0"
)

models = [convnext, resnet, vit, efficientnet]
weights = [0.28, 0.26, 0.20, 0.27]
```



#### For data loading 
```python
# Download
from datasets import load_dataset, Image
```

```python
import torch
import torch.nn as nn
import torchvision.models as models
import torchvision.transforms as transforms
from torch.utils.data import DataLoader, Dataset
from transformers import AutoImageProcessor, AutoModelForImageClassification, AutoConfig
from huggingface_hub import PyTorchModelHubMixin, hf_hub_download
from PIL import Image
import os
import numpy as np

class GPSImageDataset(Dataset):
    def __init__(self, hf_dataset, transform=None, lat_mean=None, lat_std=None, lon_mean=None, lon_std=None):
        self.hf_dataset = hf_dataset
        self.transform = transform

        # Compute mean and std from the dataframe if not provided
        self.latitude_mean = lat_mean if lat_mean is not None else np.mean(np.array(self.hf_dataset['Latitude']))
        self.latitude_std = lat_std if lat_std is not None else np.std(np.array(self.hf_dataset['Latitude']))
        self.longitude_mean = lon_mean if lon_mean is not None else np.mean(np.array(self.hf_dataset['Longitude']))
        self.longitude_std = lon_std if lon_std is not None else np.std(np.array(self.hf_dataset['Longitude']))

    def __len__(self):
        return len(self.hf_dataset)

    def __getitem__(self, idx):
        # Extract data
        example = self.hf_dataset[idx]

        # Load and process the image
        image = example['image']
        latitude = example['Latitude']
        longitude = example['Longitude']
        # image = image.rotate(-90, expand=True)
        if self.transform:
            image = self.transform(image)

        # Normalize GPS coordinates
        latitude = (latitude - self.latitude_mean) / self.latitude_std
        longitude = (longitude - self.longitude_mean) / self.longitude_std
        gps_coords = torch.tensor([latitude, longitude], dtype=torch.float32)

        return image, gps_coords
```

```python
# Dataloader + Visualize
transform = transforms.Compose([
    transforms.RandomResizedCrop(224),  # Random crop and resize to 224x224
    transforms.RandomHorizontalFlip(),  # Random horizontal flip
    # transforms.RandomRotation(degrees=15),  # Random rotation between -15 and 15 degrees
    transforms.ColorJitter(brightness=0.2, contrast=0.2, saturation=0.2, hue=0.1),  # Random color jitter
    # transforms.GaussianBlur(kernel_size=(3, 5), sigma=(0.1, 2.0)),
    # transforms.RandomPerspective(distortion_scale=0.5, p=0.5),
    transforms.ToTensor(),

    transforms.Normalize(mean=[0.485, 0.456, 0.406],
                         std=[0.229, 0.224, 0.225])
])

# Optionally, you can create a separate transform for inference without augmentations
inference_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])
])
```

Here's an exmaple of us testing the ensemble on the release test set. You can just change the load release_data line below and run the rest of the code to obtain rMSE.

```python
# Load test data
release_data = load_dataset("gydou/released_img", split="train")
```

```python
# Create dataset and dataloader using training mean and std
rel_dataset = GPSImageDataset(
    hf_dataset=release_data,
    transform=inference_transform,
    lat_mean=lat_mean,
    lat_std=lat_std,
    lon_mean=lon_mean,
    lon_std=lon_std
)
rel_dataloader = DataLoader(rel_dataset, batch_size=32, shuffle=False)
```


```python
# ensemble
ensemble_model = WeightedEnsembleModel(models=models, weights=weights).to(device)

# Validation
all_preds = []
all_actuals = []

ensemble_model.eval()
with torch.no_grad():
    for images, gps_coords in rel_dataloader:
        images, gps_coords = images.to(device), gps_coords.to(device)

        # Weighted ensemble prediction using the new model
        ensemble_logits = ensemble_model(images)

        # Denormalize predictions and actual values
        preds = ensemble_logits.cpu() * torch.tensor([lat_std, lon_std]) + torch.tensor([lat_mean, lon_mean])
        actuals = gps_coords.cpu() * torch.tensor([lat_std, lon_std]) + torch.tensor([lat_mean, lon_mean])

        all_preds.append(preds)
        all_actuals.append(actuals)

# Concatenate all batches
all_preds = torch.cat(all_preds).numpy()
all_actuals = torch.cat(all_actuals).numpy()

# Compute error metrics
mae = mean_absolute_error(all_actuals, all_preds)
rmse = mean_squared_error(all_actuals, all_preds, squared=False)

print(f'Mean Absolute Error: {mae}')
print(f'Root Mean Squared Error: {rmse}')

# Convert predictions and actuals to meters
latitude_mean_radians = np.radians(lat_mean)  # Convert to radians for cosine
meters_per_degree_latitude = 111000  # Constant
meters_per_degree_longitude = 111000 * np.cos(latitude_mean_radians)  # Adjusted for latitude mean

all_preds_meters = all_preds.copy()
all_preds_meters[:, 0] *= meters_per_degree_latitude  # Latitude to meters
all_preds_meters[:, 1] *= meters_per_degree_longitude  # Longitude to meters

all_actuals_meters = all_actuals.copy()
all_actuals_meters[:, 0] *= meters_per_degree_latitude  # Latitude to meters
all_actuals_meters[:, 1] *= meters_per_degree_longitude  # Longitude to meters

# Compute error metrics in meters
mae_meters = mean_absolute_error(all_actuals_meters, all_preds_meters)
rmse_meters = mean_squared_error(all_actuals_meters, all_preds_meters, squared=False)

print(f"Mean Absolute Error (meters): {mae_meters:.2f}")
print(f"Root Mean Squared Error (meters): {rmse_meters:.2f}")

```

After running inference on the release test set, our results are the following.
- Release Dataset Mean Absolute Error: 0.0004267849560326909
- Release Dataset Root Mean Squared Error: 0.0005247778631268114
- Mean Absolute Error (meters): 41.90
- Root Mean Squared Error (meters): 51.29