diff --git a/.claude/settings.local.json b/.claude/settings.local.json
index 8ddeffa..beb634a 100644
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -18,7 +18,8 @@
       "Bash(.venv/bin/python -m src.models.evaluate)",
       "Bash(.venv/bin/python -m src.models.evaluate --backbone resnet34 --model_path models/best_resnet34_model.pth)",
       "Bash(.venv/bin/python identify.py test_image2.jpg --backbone resnet34 --model_path models/best_resnet34_model.pth)",
-      "Bash(.venv/bin/python src/models/regression_model.py)"
+      "Bash(.venv/bin/python src/models/regression_model.py)",
+      "Bash(xargs cat -n)"
     ]
   }
 }
diff --git a/.gitignore b/.gitignore
index d5e366b..78854d7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 build/**
 **/__pycache__/**
+models/**
diff --git a/CLAUDE.md b/CLAUDE.md
index 724f881..9a4096d 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -11,10 +11,10 @@ All commands must be run from the project root using the local venv:
 .venv/bin/python identify.py <image_path>
 
 # Train the model
-.venv/bin/python -m src.models.train --epochs 50 --batch_size 64 --lr 1e-4
+.venv/bin/python -m src.models.train --epochs 50
 
 # Evaluate a trained model on val and aug_test sets
-.venv/bin/python -m src.models.evaluate [--backbone resnet18|resnet34] [--model_path <path>]
+.venv/bin/python -m src.models.evaluate [--backbone resnet34] [--model_path <path>]
 
 # Run inference only (no registry lookup)
 .venv/bin/python src/models/inference.py <image_path>
@@ -26,7 +26,7 @@ All commands must be run from the project root using the local venv:
 .venv/bin/python -m src.data.generate_aug_test_set
 
 # Generate a single sample image for visual inspection
-.venv/bin/python src/data/high_fidelity_generator.py
+.venv/bin/python src/data/renderer.py
 
 # Lint
 .venv/bin/ruff check src/
@@ -50,7 +50,7 @@ Image → Detector → Inference → Resolver → Registry
 
 ### 1. Detection (`src/utils/detector.py`)
 
-`SpindaDetector.detect_and_crop()` returns a **128×128 BGR** image, or `None`.
+`SpindaDetector.detect_and_crop()` returns a **128×128 BGR** numpy array, or `None`.
 
 Two-tier strategy, tried in order:
 - **Tier 1 (screenshots/sprites):** HSV-filter red pixels → find individual spot blobs → cluster to 4 spots → derive crop from cluster centroid + `_SPOT_CROP_RATIO=5.5` (= 128 / 24.5 px span) with a `_SPOT_CENTER_OFFSET=0.056` downward shift so the spot centroid lands at 44.4 % from the top of the crop (matching the training canvas).
@@ -58,15 +58,18 @@ Two-tier strategy, tried in order:
 
 ### 2. Model (`src/models/regression_model.py`)
 
-ResNet-18 backbone with the final FC replaced by `Linear(512, 8·16)`. Forward pass returns **(B, 8, 16)** — treating each of the 8 coordinates as a 16-class classification problem. Trained with `CrossEntropyLoss` on `view(-1, 16)` vs `view(-1)` targets; predictions use `argmax(dim=2)`.
+Configurable backbone (default: ResNet-34) with the final FC replaced by `Linear(feat_dim, 8·16)`. Forward pass returns **(B, 8, 16)** — treating each of the 8 coordinates as a 16-class classification problem. Trained with `CrossEntropyLoss` on `view(-1, 16)` vs `view(-1)` targets; predictions use `argmax(dim=2)`.
+
+Supported backbones: `resnet18` (512-d), `resnet34` (512-d), `convnext_tiny` (768-d).
 
 ### 3. Training (`src/models/train.py`)
 
 - `SpindaDataset` (200 k virtual samples/epoch): generates a fresh random 32-bit PID per `__getitem__`, renders the sprite with a random background colour, then applies the full augmentation pipeline.
-- `SpindaEvalDataset`: loads pre-generated images from disk (post-augmentation, pre-normalisation) and applies only the normalise step. Used for both `data/val/` (clean, seed=42) and `data/aug_test/` (augmented, seed=99).
+- `SpindaEvalDataset` (in `src/data/dataset.py`): loads pre-generated images from disk (post-augmentation, pre-normalisation) and applies only the normalise step. Used for both `data/val/` (clean, seed=42) and `data/aug_test/` (augmented, seed=99).
 - `_worker_init_fn` re-seeds Python `random` and NumPy per worker so forked workers generate distinct PIDs.
+- Weighted loss: BL_x ×1.5, BL_y ×2.5 — applied during training only; val loss is unweighted.
 - Early stopping: patience = 10 epochs on clean-val exact-match rate.
-- Best model checkpoint: `models/best_spinda_model.pth`.
+- Checkpoints saved to `models/best_{backbone}_model.pth`.
 
 ### 4. PID Encoding (domain invariant — must not be changed)
 
@@ -107,7 +110,8 @@ assets/            # Sprite assets used by the renderer
   Spot_{TL,TR,BL,BR}.png
 
 models/
-  best_spinda_model.pth
+  best_resnet34_model.pth      # current best (default)
+  best_convnext_tiny_model.pth # convnext experiment
 ```
 
 `metadata.json` format: `[{"img_path": "...", "pid_hex": "...", "target": [int×8]}, ...]`
@@ -115,8 +119,8 @@ models/
 ## Key invariants
 
 - **Visual collisions:** ~1.3 % of fingerprints are shared by multiple PIDs (many-to-one mapping). `SpindaRegistry` stores `(fingerprint, pid_hex)` pairs with a unique constraint so `lookup_by_fingerprint` can return *all* matching PIDs — this is intentional, not a bug.
-
 - The **validation set** uses white backgrounds (no augmentation baked in) to give a stable epoch-comparable baseline. Do not add augmentation to `generate_val_set.py`.
 - The **augmented test set** is pre-generated and fixed. Regenerating it changes the baseline; do so intentionally.
 - The crop output size is always **128×128** regardless of tier. The model transform chain also resizes to 128×128, so the inference path is robust to re-size.
-- `generate_high_fidelity_spinda()` always takes `bg_color` as a `(R, G, B)` tuple in PIL order (not BGR).
+- `generate_high_fidelity_spinda()` in `src/data/renderer.py` always takes `bg_color` as a `(R, G, B)` tuple in PIL order (not BGR).
+- `SpindaInference.predict()` accepts either a file path or a BGR numpy array directly (e.g. from the detector).
diff --git a/identify.py b/identify.py
index 6343279..dd3563c 100644
--- a/identify.py
+++ b/identify.py
@@ -1,70 +1,59 @@
+import argparse
 import os
 import sys
+
 import cv2
-import torch
+
+from src.data.renderer import generate_high_fidelity_spinda
 from src.models.inference import SpindaInference
-from src.utils.resolver import SpindaResolver
 from src.registry.database import SpindaRegistry
-from src.data.high_fidelity_generator import generate_high_fidelity_spinda
-from src.utils.detector import SpindaDetector # Import the detector
+from src.utils.detector import SpindaDetector
+from src.utils.resolver import SpindaResolver
+
 
 def identify_spinda(
     image_path: str,
-    model_path: str = "models/best_spinda_model.pth",
-    backbone: str = "resnet18",
-):
+    model_path: str = "models/best_resnet34_model.pth",
+    backbone: str = "resnet34",
+) -> None:
     if not os.path.exists(image_path):
         print(f"Error: File {image_path} not found.")
         return
 
     print(f"--- Identifying Spinda in {image_path} ---")
-    
-    # 1. Detect and Crop Spinda
+
+    # 1. Detect and crop
     detector = SpindaDetector()
     cropped_img = detector.detect_and_crop(image_path)
-
     if cropped_img is None:
         print("Error: Could not detect Spinda in the image.")
         return
-    
-    # Save cropped image for debug/visual check
+
     cv2.imwrite("detected_spinda_crop.png", cropped_img)
     print("Detected Spinda saved to detected_spinda_crop.png")
 
-    # We need to save the cropped image to a temporary file for the inference model to read
-    temp_cropped_path = "temp_cropped_spinda.png"
-    cv2.imwrite(temp_cropped_path, cropped_img)
-
-    # 2. Inference (Model Prediction) using the cropped image
-    try:
-        inf = SpindaInference(model_path=model_path, backbone=backbone)
-        coords, fingerprint = inf.predict(temp_cropped_path)
-    except Exception as e:
-        print(f"Error during inference: {e}")
-        os.remove(temp_cropped_path) # Clean up temp file
-        return
-    finally:
-        os.remove(temp_cropped_path) # Clean up temp file
+    # 2. Inference — pass the BGR array directly, no temp file needed
+    inf = SpindaInference(model_path=model_path, backbone=backbone)
+    coords, fingerprint = inf.predict(cropped_img)
 
     print(f"Visual Fingerprint: {fingerprint}")
     print(f"Predicted Grid Coordinates: {coords}")
 
-    # 3. Resolution (Mathematical PIDs)
+    # 3. Resolve to PIDs
     resolved = SpindaResolver.resolve_fingerprint(fingerprint)
     print("\nPossible PIDs:")
     print(f"  Standard (Gen 3-8, HOME): 0x{resolved['standard']}")
     print(f"  BDSP (Big-Endian Flip):   0x{resolved['bdsp']}")
 
-    # 4. Visual Verification
+    # 4. Visual verification
     print("\nGenerating visual verification image...")
     verify_img = generate_high_fidelity_spinda(int(resolved['standard'], 16))
     cv2.imwrite("prediction_verify.png", verify_img)
     print("Verification image saved to: prediction_verify.png")
 
-    # 5. Registry Lookup
+    # 5. Registry lookup
     reg = SpindaRegistry()
     matches = reg.lookup_by_fingerprint(fingerprint)
-    
     if matches:
         print("\nMatches found in Global Registry:")
         for pid in matches:
@@ -72,13 +61,12 @@ def identify_spinda(
     else:
         print("\nNo matching entries in Global Registry.")
 
-    print("\nNote: Accuracy depends on model training progress.")
 
 if __name__ == "__main__":
-    import argparse
     parser = argparse.ArgumentParser()
     parser.add_argument("image_path")
-    parser.add_argument("--backbone",   type=str, default="resnet18", choices=["resnet18", "resnet34", "convnext_tiny"])
-    parser.add_argument("--model_path", type=str, default="models/best_spinda_model.pth")
+    parser.add_argument("--backbone",   type=str, default="resnet34",
+                        choices=["resnet18", "resnet34", "convnext_tiny"])
+    parser.add_argument("--model_path", type=str, default="models/best_resnet34_model.pth")
     args = parser.parse_args()
     identify_spinda(args.image_path, model_path=args.model_path, backbone=args.backbone)
diff --git a/models/best_spinda_model.pth b/models/best_spinda_model.pth
index 4199b86..c175e04 100644
Binary files a/models/best_spinda_model.pth and b/models/best_spinda_model.pth differ
diff --git a/pyproject.toml b/pyproject.toml
index 57a13a7..b7eb365 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -9,6 +9,7 @@ dependencies = [
     "opencv-python>=4.7.0",
     "Pillow>=9.5.0",
     "numpy>=1.24.0",
+    "tqdm>=4.65.0",
 ]
 
 [project.optional-dependencies]
@@ -16,7 +17,6 @@ dev = [
     "pytest>=7.3.0",
     "ruff>=0.0.270",
     "mypy>=1.3.0",
-    "tqdm>=4.65.0",
 ]
 
 [tool.ruff]
diff --git a/src/data/dataset.py b/src/data/dataset.py
index e4a12c4..04fdb67 100644
--- a/src/data/dataset.py
+++ b/src/data/dataset.py
@@ -1,69 +1,52 @@
-import torch
-from torch.utils.data import Dataset
-import torchvision.transforms.v2 as T
-import numpy as np
-from typing import Tuple, Optional
+import json
+import os
 import random
+from typing import Optional
+
+import cv2
+import torch
+import torchvision.transforms.v2 as T
+from torch.utils.data import Dataset
+
+from src.data.renderer import generate_high_fidelity_spinda
+from src.utils.resolver import SpindaResolver
 
-from src.data.high_fidelity_generator import generate_high_fidelity_spinda
 
 class SpindaDataset(Dataset):
     """PyTorch Dataset for generating synthetic Spinda samples with augmentations."""
-    
+
     def __init__(self, size: int = 10000, transform: Optional[T.Transform] = None):
-        """
-        Args:
-            size: Virtual size of the dataset (since it's synthetic).
-            transform: Optional torchvision transforms to apply.
-        """
         self.size = size
         self.transform = transform
 
     def __len__(self) -> int:
         return self.size
 
-    def __getitem__(self, idx: int) -> Tuple[torch.Tensor, torch.Tensor]:
-        # Generate a random 32-bit PID
+    def __getitem__(self, idx: int) -> tuple[torch.Tensor, torch.Tensor]:
         pid = random.getrandbits(32)
         pid_hex = f"{pid:08x}"
-        
-        # 1. Generate High-Fidelity Image on a random background colour
+
         r = random.randint(0, 255)
         g = random.randint(0, 255)
         b = random.randint(0, 255)
         img_bgr = generate_high_fidelity_spinda(pid, bg_color=(r, g, b))
-        
-        # Convert BGR to RGB for PyTorch/Torchvision
         img_rgb = img_bgr[:, :, ::-1].copy()
-        
-        # 2. Get Ground Truth Coordinates (Target)
-        # Raw nibble values (0-15) for each spot, in TL/TR/BL/BR order.
-        raw_coords = []
-        # TL (Spot 1): Nibble 0, 1 (PID[-1], PID[-2])
-        raw_coords.extend([int(pid_hex[-1], 16), int(pid_hex[-2], 16)])
-        # TR (Spot 2): Nibble 2, 3 (PID[-3], PID[-4])
-        raw_coords.extend([int(pid_hex[-3], 16), int(pid_hex[-4], 16)])
-        # BL (Spot 3): Nibble 4, 5 (PID[3], PID[2])
-        raw_coords.extend([int(pid_hex[3], 16), int(pid_hex[2], 16)])
-        # BR (Spot 4): Nibble 6, 7 (PID[1], PID[0])
-        raw_coords.extend([int(pid_hex[1], 16), int(pid_hex[0], 16)])
-        
-        # Integer labels in [0, 15] — used with CrossEntropyLoss.
-        target_tensor = torch.tensor(raw_coords, dtype=torch.long)
-        
-        # 3. Apply Transforms
+
+        target_tensor = torch.tensor(SpindaResolver.pid_to_coords(pid_hex), dtype=torch.long)
+
         if self.transform:
-            # Convert to PIL or Tensor first if needed by transform
-            img_tensor = torch.from_numpy(img_rgb).permute(2, 0, 1) # C, H, W
+            img_tensor = torch.from_numpy(img_rgb).permute(2, 0, 1)
             img_tensor = self.transform(img_tensor)
         else:
             img_tensor = torch.from_numpy(img_rgb).permute(2, 0, 1).float() / 255.0
-            
+
         return img_tensor, target_tensor
 
+
 def add_gaussian_noise(x: torch.Tensor) -> torch.Tensor:
     return (x + torch.randn_like(x) * 0.05).clamp(0, 1)
 
+
 def add_scan_lines(x: torch.Tensor) -> torch.Tensor:
     """Simulate LCD scan lines seen in handheld-camera photos of 3DS screens."""
     if torch.rand(1).item() < 0.5:
@@ -72,26 +55,52 @@ def add_scan_lines(x: torch.Tensor) -> torch.Tensor:
         x[:, ::2, :] *= (1.0 - strength)
     return x.clamp(0, 1)
 
+
 def get_default_augmentations() -> T.Compose:
     """Domain randomisation pipeline calibrated for real handheld-photo conditions."""
     return T.Compose([
         T.ToDtype(torch.float32, scale=True),
-        # Spatial — wider range to cover camera angle and zoom variation
         T.RandomAffine(degrees=25, translate=(0.05, 0.05), shear=8),
         T.RandomResizedCrop(size=(128, 128), scale=(0.75, 1.0), ratio=(0.85, 1.15), antialias=True),
-        # Colour / sensor — stronger to cover screen glare and ambient lighting
         T.ColorJitter(brightness=0.4, contrast=0.4, saturation=0.3, hue=0.05),
         T.GaussianBlur(kernel_size=(3, 3), sigma=(0.1, 2.0)),
-        # Sensor noise and LCD scan lines
         T.Lambda(add_gaussian_noise),
         T.Lambda(add_scan_lines),
         T.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
     ])
 
+
+class SpindaEvalDataset(Dataset):
+    """Loads a fixed evaluation set (clean val or augmented test).
+
+    Images are stored post-augmentation, pre-normalisation; this class
+    applies only the normalisation step so the on-disk images are stable.
+    """
+
+    def __init__(self, data_dir: str):
+        with open(os.path.join(data_dir, "metadata.json")) as f:
+            self.metadata = json.load(f)
+        self.transform = T.Compose([
+            T.ToDtype(torch.float32, scale=True),
+            T.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
+        ])
+
+    def __len__(self) -> int:
+        return len(self.metadata)
+
+    def __getitem__(self, idx: int) -> tuple[torch.Tensor, torch.Tensor]:
+        item = self.metadata[idx]
+        img_bgr = cv2.imread(item["img_path"])
+        if img_bgr is None:
+            raise FileNotFoundError(f"Image not found: {item['img_path']}")
+        img_rgb = img_bgr[:, :, ::-1].copy()
+        img_tensor = self.transform(torch.from_numpy(img_rgb).permute(2, 0, 1))
+        target = torch.tensor(item["target"], dtype=torch.long)
+        return img_tensor, target
+
+
 if __name__ == "__main__":
-    # Test the dataset
     ds = SpindaDataset(size=5, transform=get_default_augmentations())
     img, target = ds[0]
     print(f"Image shape: {img.shape}")
-    print(f"Target (normalized 0-1): {target}")
-    print(f"Target (grid units): {target * 15.0}")
+    print(f"Target: {target.tolist()}")
diff --git a/src/data/generate_aug_test_set.py b/src/data/generate_aug_test_set.py
index 17dcbb6..db9a546 100644
--- a/src/data/generate_aug_test_set.py
+++ b/src/data/generate_aug_test_set.py
@@ -15,7 +15,8 @@ import torchvision.transforms.v2 as T
 from tqdm import tqdm
 
 from src.data.dataset import add_gaussian_noise, add_scan_lines
-from src.data.high_fidelity_generator import generate_high_fidelity_spinda
+from src.data.renderer import generate_high_fidelity_spinda
+from src.utils.resolver import SpindaResolver
 
 
 # Augmentation without the final Normalize step — we bake everything else in.
@@ -53,13 +54,11 @@ def generate_aug_test_set(size: int = 500, output_dir: str = "data/aug_test") ->
         img_path = os.path.join(output_dir, f"sample_{i:04d}.png")
         cv2.imwrite(img_path, aug_bgr)
 
-        raw_coords = [
-            int(pid_hex[-1], 16), int(pid_hex[-2], 16),
-            int(pid_hex[-3], 16), int(pid_hex[-4], 16),
-            int(pid_hex[3],  16), int(pid_hex[2],  16),
-            int(pid_hex[1],  16), int(pid_hex[0],  16),
-        ]
-        metadata.append({"img_path": img_path, "pid_hex": pid_hex, "target": raw_coords})
+        metadata.append({
+            "img_path": img_path,
+            "pid_hex": pid_hex,
+            "target": SpindaResolver.pid_to_coords(pid_hex),
+        })
 
     with open(os.path.join(output_dir, "metadata.json"), "w") as f:
         json.dump(metadata, f, indent=4)
diff --git a/src/data/generate_val_set.py b/src/data/generate_val_set.py
index bce0c82..5ae78dd 100644
--- a/src/data/generate_val_set.py
+++ b/src/data/generate_val_set.py
@@ -1,47 +1,40 @@
-import os
-import torch
 import json
+import os
 import random
-from tqdm import tqdm
-from src.data.high_fidelity_generator import generate_high_fidelity_spinda
-import cv2
 
-def generate_fixed_val_set(size: int = 1000, output_dir: str = "data/val"):
+import cv2
+from tqdm import tqdm
+
+from src.data.renderer import generate_high_fidelity_spinda
+from src.utils.resolver import SpindaResolver
+
+
+def generate_fixed_val_set(size: int = 1000, output_dir: str = "data/val") -> None:
     """Generates a fixed set of Spinda images and their targets for validation."""
     os.makedirs(output_dir, exist_ok=True)
-    
     metadata = []
-    
+
     print(f"Generating {size} validation samples...")
     for i in tqdm(range(size)):
         pid = random.getrandbits(32)
         pid_hex = f"{pid:08x}"
-        
-        # Generate image
+
         img_bgr = generate_high_fidelity_spinda(pid)
         img_path = os.path.join(output_dir, f"sample_{i:04d}.png")
         cv2.imwrite(img_path, img_bgr)
-        
-        # Extract raw coordinates (0-15)
-        raw_coords = [
-            int(pid_hex[-1], 16), int(pid_hex[-2], 16),
-            int(pid_hex[-3], 16), int(pid_hex[-4], 16),
-            int(pid_hex[3], 16), int(pid_hex[2], 16),
-            int(pid_hex[1], 16), int(pid_hex[0], 16)
-        ]
-        
+
         metadata.append({
             "img_path": img_path,
             "pid_hex": pid_hex,
-            "target": raw_coords
+            "target": SpindaResolver.pid_to_coords(pid_hex),
         })
-        
+
     with open(os.path.join(output_dir, "metadata.json"), "w") as f:
         json.dump(metadata, f, indent=4)
-        
+
     print(f"Validation set generated in {output_dir}")
 
+
 if __name__ == "__main__":
-    # Seed for reproducibility of the validation set itself
     random.seed(42)
     generate_fixed_val_set()
diff --git a/src/data/generator.py b/src/data/generator.py
deleted file mode 100644
index 10b4b7d..0000000
--- a/src/data/generator.py
+++ /dev/null
@@ -1,81 +0,0 @@
-import numpy as np
-import cv2
-from typing import Tuple, List
-
-# Image and Grid constants
-IMG_SIZE = 128
-GRID_SIZE = 16
-SPOT_RADIUS = 6  # Approximate radius in pixels
-
-# Colors (BGR)
-FACE_COLOR = (180, 220, 240)  # Pale cream/tan
-SPOT_COLOR = (50, 50, 200)    # Reddish-orange
-EYE_COLOR = (0, 0, 0)
-
-def extract_coords(pid: int, mode: str = "standard") -> List[Tuple[int, int]]:
-    """Extracts four (x, y) coordinates from a 32-bit PID/EC.
-    
-    Standard (Little-Endian): Byte 0 (LL), 1 (LR), 2 (UL), 3 (UR)
-    BDSP (Big-Endian): Byte 3 (LL), 2 (LR), 1 (UL), 0 (UR)
-    """
-    bytes_list = [
-        (pid >> 0) & 0xFF,   # Byte 0
-        (pid >> 8) & 0xFF,   # Byte 1
-        (pid >> 16) & 0xFF,  # Byte 2
-        (pid >> 24) & 0xFF,  # Byte 3
-    ]
-    
-    if mode == "bdsp":
-        # BDSP reads the bytes in reverse order
-        ordered_bytes = [bytes_list[3], bytes_list[2], bytes_list[1], bytes_list[0]]
-    else:
-        ordered_bytes = bytes_list
-
-    coords = []
-    for byte in ordered_bytes:
-        x = byte & 0x0F
-        y = (byte >> 4) & 0x0F
-        coords.append((x, y))
-    return coords
-
-def generate_spinda_face(pid: int, mode: str = "standard") -> np.ndarray:
-    """Generates a procedural Spinda face with spots based on the PID."""
-    # Create blank canvas (white)
-    img = np.ones((IMG_SIZE, IMG_SIZE, 3), dtype=np.uint8) * 255
-    
-    # Draw Ears
-    cv2.circle(img, (IMG_SIZE // 2 - 40, IMG_SIZE // 2 - 50), 20, FACE_COLOR, -1)
-    cv2.circle(img, (IMG_SIZE // 2 - 40, IMG_SIZE // 2 - 50), 20, (0, 0, 0), 2)
-    cv2.circle(img, (IMG_SIZE // 2 + 40, IMG_SIZE // 2 - 50), 20, FACE_COLOR, -1)
-    cv2.circle(img, (IMG_SIZE // 2 + 40, IMG_SIZE // 2 - 50), 20, (0, 0, 0), 2)
-
-    # Draw main face (oval)
-    center = (IMG_SIZE // 2, IMG_SIZE // 2)
-    axes = (50, 60)
-    cv2.ellipse(img, center, axes, 0, 0, 360, FACE_COLOR, -1)
-    cv2.ellipse(img, center, axes, 0, 0, 360, (0, 0, 0), 2)  # Outline
-    
-    # Fixed Eyes
-    cv2.circle(img, (center[0] - 15, center[1] - 10), 4, EYE_COLOR, -1)
-    cv2.circle(img, (center[0] + 15, center[1] - 10), 4, EYE_COLOR, -1)
-    
-    # Define Spot Zones (Relative to the 16x16 grid)
-    # Heuristic mapping for a more "Pokemon-like" layout
-    # Spot 1 (LL), Spot 2 (LR), Spot 3 (UL), Spot 4 (UR)
-    # These offsets are designed to place spots in their respective quadrants
-    quadrant_offsets = [
-        (center[0] - 45, center[1] + 5),  # LL (Face)
-        (center[0] + 5, center[1] + 5),   # LR (Face)
-        (center[0] - 45, center[1] - 55), # UL (Ear/Upper Face)
-        (center[0] + 5, center[1] - 55),  # UR (Ear/Upper Face)
-    ]
-    
-    coords = extract_coords(pid, mode=mode)
-    for i, (x, y) in enumerate(coords):
-        offset_x, offset_y = quadrant_offsets[i]
-        px = int(offset_x + x * 2.5) # Scale grid to quadrant
-        py = int(offset_y + y * 2.5)
-        
-        cv2.circle(img, (px, py), SPOT_RADIUS, SPOT_COLOR, -1)
-        
-    return img
diff --git a/src/data/high_fidelity_generator.py b/src/data/renderer.py
similarity index 53%
rename from src/data/high_fidelity_generator.py
rename to src/data/renderer.py
index 93546e2..84abdc5 100644
--- a/src/data/high_fidelity_generator.py
+++ b/src/data/renderer.py
@@ -1,15 +1,14 @@
-import numpy as np
-import cv2
-from PIL import Image
 import os
-from typing import List, Tuple
+
+import cv2
+import numpy as np
+from PIL import Image
 
 # Constants
 IMG_SIZE = 128
-BASE_PATH = "assets"
+BASE_PATH = os.path.normpath(os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "..", "assets"))
 
 # Offsets from ProfessorRex's Spinda_generator.py (Observer Perspective)
-# This matches the script's PID_to_Coordinates logic:
 # TL (Spot 1): Nibble 0, 1 (PID[-1], PID[-2])
 # TR (Spot 2): Nibble 2, 3 (PID[-3], PID[-4]) + (24, 1)
 # BL (Spot 3): Nibble 4, 5 (PID[3], PID[2]) + (6, 18)
@@ -21,10 +20,9 @@ SPOT_BASE_OFFSETS = [
     (18, 19),  # Spot 4 (BR)
 ]
 
-def extract_coords_rex(pid_hex: str) -> List[Tuple[int, int]]:
-    """Extracts coordinates following ProfessorRex's PID_to_Coordinates logic.
-    PID is expected to be an 8-char hex string.
-    """
+
+def extract_coords_rex(pid_hex: str) -> list[tuple[int, int]]:
+    """Extracts coordinates following ProfessorRex's PID_to_Coordinates logic."""
     pid = pid_hex.lower().zfill(8)
     TL = (int(pid[-1], 16), int(pid[-2], 16))
     TR = (int(pid[-3], 16) + 24, int(pid[-4], 16) + 1)
@@ -32,64 +30,52 @@ def extract_coords_rex(pid_hex: str) -> List[Tuple[int, int]]:
     BR = (int(pid[1], 16) + 18, int(pid[0], 16) + 19)
     return [TL, TR, BL, BR]
 
+
 def generate_high_fidelity_spinda(
     pid: int,
     bg_color: tuple[int, int, int] = (255, 255, 255),
 ) -> np.ndarray:
     """Generates a high-fidelity Spinda face using correctly sized assets."""
     pid_hex = f"{pid:08x}"
-    
+
     # 1. Load Assets
     base_img = Image.open(os.path.join(BASE_PATH, "Spinda_Base_Top.png")).convert("RGBA")
     head_img = Image.open(os.path.join(BASE_PATH, "Spinda_Head.png")).convert("RGBA")
     head_data = np.array(head_img)
-    
-    spot_names = ["Spot_TL.png", "Spot_TR.png", "Spot_BL.png", "Spot_BR.png"]
-    spots = [Image.open(os.path.join(BASE_PATH, name)).convert("RGBA") for name in spot_names]
-    
-    # 2. Create Pattern Layer (Integer grid like in Rex's script)
-    W, H = base_img.size
-    pattern_grid = np.zeros((H, W), dtype=np.uint8)
-    
-    coords = extract_coords_rex(pid_hex)
-    
-    for i, (px_start, py_start) in enumerate(coords):
-        spot_arr = np.array(spots[i])
-        sh, sw = spot_arr.shape[:2]
-        
-        for sy in range(sh):
-            for sx in range(sw):
-                # If spot pixel is white (active) in the mask
-                # Check for white pixels (R,G,B > 200)
-                if spot_arr[sy, sx, 0] > 200:
-                    tx, ty = px_start + sx, py_start + sy
-                    if 0 <= tx < W and 0 <= ty < H:
-                        # Mark as active
-                        pattern_grid[ty, tx] = 1
 
-    # 3. Colourize
-    # Create an empty RGBA layer for the spots
+    spot_names = ["Spot_TL.png", "Spot_TR.png", "Spot_BL.png", "Spot_BR.png"]
+    spots = [np.array(Image.open(os.path.join(BASE_PATH, name)).convert("RGBA")) for name in spot_names]
+
+    # 2. Build pattern grid — mark pixels covered by any spot
+    W, H = base_img.size
+    pattern_grid = np.zeros((H, W), dtype=bool)
+
+    for spot_arr, (px_start, py_start) in zip(spots, extract_coords_rex(pid_hex)):
+        sh, sw = spot_arr.shape[:2]
+        active = spot_arr[:, :, 0] > 200          # white pixels in the spot mask
+        ys, xs = np.where(active)
+        tx = px_start + xs
+        ty = py_start + ys
+        valid = (tx >= 0) & (tx < W) & (ty >= 0) & (ty < H)
+        pattern_grid[ty[valid], tx[valid]] = True
+
+    # 3. Colourize — copy head colours onto active spot pixels
     spot_layer = np.zeros((H, W, 4), dtype=np.uint8)
-    for y in range(H):
-        for x in range(W):
-            if pattern_grid[y, x] > 0:
-                # Take color from Spinda_Head.png
-                spot_layer[y, x] = head_data[y, x]
+    spot_layer[pattern_grid] = head_data[pattern_grid]
 
     # 4. Composite
-    spot_layer_img = Image.fromarray(spot_layer, "RGBA")
-    combined = Image.alpha_composite(base_img, spot_layer_img)
-    
-    # 5. Final Canvas (128x128)
+    combined = Image.alpha_composite(base_img, Image.fromarray(spot_layer, "RGBA"))
+
+    # 5. Final Canvas (128×128)
     final_img = Image.new("RGBA", (IMG_SIZE, IMG_SIZE), (*bg_color, 255))
     offset = ((IMG_SIZE - W) // 2, (IMG_SIZE - H) // 2)
     final_img.paste(combined, offset, combined)
-    
+
     return cv2.cvtColor(np.array(final_img), cv2.COLOR_RGBA2BGR)
 
+
 if __name__ == "__main__":
-    # Test with 0x12345678
     test_pid = 0x12345678
     img = generate_high_fidelity_spinda(test_pid)
-    cv2.imwrite("sample_high_fidelity_v3.png", img)
-    print(f"Corrected High-fidelity sample saved to sample_high_fidelity_v3.png for PID: {hex(test_pid)}")
+    cv2.imwrite("sample_spinda.png", img)
+    print(f"Sample saved to sample_spinda.png for PID: {hex(test_pid)}")
diff --git a/src/data/visualize_sample.py b/src/data/visualize_sample.py
deleted file mode 100644
index b8170fc..0000000
--- a/src/data/visualize_sample.py
+++ /dev/null
@@ -1,21 +0,0 @@
-import cv2
-from src.data.generator import generate_spinda_face
-
-def save_sample_image():
-    # Example PID (from documentation/common examples if possible)
-    # Let's use a PID that should have distinct spots
-    # 0x12345678 -> 
-    # Byte 0: 0x78 (X=8, Y=7)
-    # Byte 1: 0x56 (X=6, Y=5)
-    # Byte 2: 0x34 (X=4, Y=3)
-    # Byte 3: 0x12 (X=2, Y=1)
-    test_pid = 0x12345678
-    
-    img = generate_spinda_face(test_pid)
-    
-    # Save the image
-    cv2.imwrite("sample_spinda.png", img)
-    print(f"Sample Spinda image saved to sample_spinda.png for PID: {hex(test_pid)}")
-
-if __name__ == "__main__":
-    save_sample_image()
diff --git a/src/models/evaluate.py b/src/models/evaluate.py
index 073f430..a120672 100644
--- a/src/models/evaluate.py
+++ b/src/models/evaluate.py
@@ -5,7 +5,7 @@ import torch
 from torch.utils.data import DataLoader
 
 from src.models.regression_model import SpindaRegressionModel
-from src.models.train import SpindaEvalDataset
+from src.data.dataset import SpindaEvalDataset
 
 
 def evaluate(model: torch.nn.Module, device: torch.device, name: str, ds: SpindaEvalDataset) -> None:
@@ -29,8 +29,8 @@ def evaluate(model: torch.nn.Module, device: torch.device, name: str, ds: Spinda
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser()
-    parser.add_argument("--model_path", type=str, default="models/best_spinda_model.pth")
-    parser.add_argument("--backbone",   type=str, default="resnet18", choices=["resnet18", "resnet34", "convnext_tiny"])
+    parser.add_argument("--model_path", type=str, default="models/best_resnet34_model.pth")
+    parser.add_argument("--backbone",   type=str, default="resnet34", choices=["resnet18", "resnet34", "convnext_tiny"])
     args = parser.parse_args()
 
     if not os.path.exists(args.model_path):
diff --git a/src/models/inference.py b/src/models/inference.py
index b808109..23a68fc 100644
--- a/src/models/inference.py
+++ b/src/models/inference.py
@@ -2,8 +2,7 @@ import cv2
 import numpy as np
 import torch
 import torchvision.transforms.v2 as T
-from PIL import Image
-from typing import List, Tuple
+from typing import List, Tuple, Union
 
 from src.models.regression_model import SpindaRegressionModel
 
@@ -13,8 +12,8 @@ class SpindaInference:
 
     def __init__(
         self,
-        model_path: str = "models/best_spinda_model.pth",
-        backbone: str = "resnet18",
+        model_path: str = "models/best_resnet34_model.pth",
+        backbone: str = "resnet34",
     ):
         self.device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
         self.model = SpindaRegressionModel(pretrained=False, backbone=backbone)
@@ -29,15 +28,23 @@ class SpindaInference:
             T.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
         ])
 
-    def predict(self, image_path: str) -> Tuple[List[int], str]:
+    def predict(self, image: Union[str, np.ndarray]) -> Tuple[List[int], str]:
         """Predict the 8 grid coordinates and return them with a fingerprint string.
 
+        Args:
+            image: file path (str) or a BGR numpy array (e.g. from the detector).
         Returns:
             grid_coords: list of 8 integers in [0, 15]
             fingerprint: "X1-Y1-X2-Y2-X3-Y3-X4-Y4"
         """
-        img_bgr = cv2.imread(image_path)
-        img_rgb = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)
+        if isinstance(image, str):
+            img_bgr = cv2.imread(image)
+            if img_bgr is None:
+                raise FileNotFoundError(f"Image not found: {image}")
+            img_rgb = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)
+        else:
+            img_rgb = image[:, :, ::-1].copy()
+
         img_tensor = torch.from_numpy(np.array(img_rgb)).permute(2, 0, 1)
         img_tensor = self.transform(img_tensor).unsqueeze(0).to(self.device)
 
diff --git a/src/models/regression_model.py b/src/models/regression_model.py
index 473959f..17130d2 100644
--- a/src/models/regression_model.py
+++ b/src/models/regression_model.py
@@ -23,7 +23,7 @@ class SpindaRegressionModel(nn.Module):
     Prediction:   output.argmax(dim=2)  →  (B, 8) integer coordinates.
     """
 
-    def __init__(self, pretrained: bool = True, backbone: str = "resnet18"):
+    def __init__(self, pretrained: bool = True, backbone: str = "resnet34"):
         super().__init__()
         if backbone not in _BACKBONES:
             raise ValueError(f"backbone must be one of {list(_BACKBONES)}; got {backbone!r}")
diff --git a/src/models/train.py b/src/models/train.py
index 0049a59..43aa06d 100644
--- a/src/models/train.py
+++ b/src/models/train.py
@@ -1,49 +1,17 @@
 import os
-import json
 import random
 
-import cv2
 import numpy as np
 import torch
-import torch.nn as nn
 import torch.nn.functional as F
 import torch.optim as optim
-import torchvision.transforms.v2 as T
-from torch.utils.data import DataLoader, Dataset
+from torch.utils.data import DataLoader
 from tqdm import tqdm
 
-from src.data.dataset import SpindaDataset, get_default_augmentations
+from src.data.dataset import SpindaDataset, SpindaEvalDataset, get_default_augmentations
 from src.models.regression_model import SpindaRegressionModel
 
 
-class SpindaEvalDataset(Dataset):
-    """Loads a fixed evaluation set (clean val or augmented test).
-
-    Images are stored post-augmentation, pre-normalisation; this class
-    applies only the normalisation step so the on-disk images are stable.
-    """
-
-    def __init__(self, data_dir: str):
-        with open(os.path.join(data_dir, "metadata.json")) as f:
-            self.metadata = json.load(f)
-        self.transform = T.Compose([
-            T.ToDtype(torch.float32, scale=True),
-            T.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
-        ])
-
-    def __len__(self) -> int:
-        return len(self.metadata)
-
-    def __getitem__(self, idx: int) -> tuple[torch.Tensor, torch.Tensor]:
-        item = self.metadata[idx]
-        img_bgr = cv2.imread(item["img_path"])
-        img_rgb = img_bgr[:, :, ::-1].copy()
-        img_tensor = torch.from_numpy(img_rgb).permute(2, 0, 1)
-        img_tensor = self.transform(img_tensor)
-        target = torch.tensor(item["target"], dtype=torch.long)
-        return img_tensor, target
-
-
 # BL_x (index 4) and BL_y (index 5) are the weakest coordinates; upweight them
 # so the optimiser focuses more of its gradient on the hardest spot.
 _COORD_WEIGHTS = torch.tensor([1.0, 1.0, 1.0, 1.0, 1.5, 2.5, 1.0, 1.0])
@@ -73,7 +41,7 @@ def train_model(
     model_path: str = "models/best_spinda_model.pth",
     num_workers: int = 4,
     epoch_size: int = 200000,
-    backbone: str = "resnet18",
+    backbone: str = "resnet34",
     save_path: str = "",
 ) -> None:
     device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
@@ -176,8 +144,7 @@ def train_model(
         if exact_rate > best_exact_rate:
             best_exact_rate = exact_rate
             epochs_without_improvement = 0
-            os.makedirs("models", exist_ok=True)
-            os.makedirs(os.path.dirname(checkpoint_path), exist_ok=True)
+            os.makedirs(os.path.dirname(checkpoint_path) or ".", exist_ok=True)
             torch.save(model.state_dict(), checkpoint_path)
             print(f"  → Saved best model to {checkpoint_path} (clean val exact match: {best_exact_rate:.2%})")
         else:
@@ -198,7 +165,7 @@ if __name__ == "__main__":
     parser.add_argument("--model_path",  type=str,   default="models/best_spinda_model.pth")
     parser.add_argument("--num_workers", type=int,   default=4,      help="DataLoader worker count (0 = main process only)")
     parser.add_argument("--epoch_size",  type=int,   default=200000, help="Virtual dataset size per epoch")
-    parser.add_argument("--backbone",    type=str,   default="resnet18", choices=["resnet18", "resnet34", "convnext_tiny"])
+    parser.add_argument("--backbone",    type=str,   default="resnet34", choices=["resnet18", "resnet34", "convnext_tiny"])
     parser.add_argument("--save_path",   type=str,   default="",     help="Override checkpoint save path")
     args = parser.parse_args()
 
diff --git a/src/registry/database.py b/src/registry/database.py
index c6e6ede..ac72415 100644
--- a/src/registry/database.py
+++ b/src/registry/database.py
@@ -1,21 +1,18 @@
-import sqlite3
 import os
-from typing import List, Optional, Tuple
+import sqlite3
+
 
 class SpindaRegistry:
     """Handles the storage and lookup of Spinda PIDs based on their visual fingerprints."""
-    
+
     def __init__(self, db_path: str = "data/spinda_registry.db"):
         self.db_path = db_path
-        os.makedirs(os.path.dirname(self.db_path), exist_ok=True)
+        os.makedirs(os.path.dirname(db_path) or ".", exist_ok=True)
         self._init_db()
 
-    def _init_db(self):
-        """Initializes the database with a core table for PIDs and Fingerprints."""
+    def _init_db(self) -> None:
         with sqlite3.connect(self.db_path) as conn:
             cursor = conn.cursor()
-            # Primary table: Mapping the 8-integer fingerprint to PIDs
-            # Fingerprint format: "X1-Y1-X2-Y2-X3-Y3-X4-Y4"
             cursor.execute('''
                 CREATE TABLE IF NOT EXISTS registry (
                     id INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -24,38 +21,34 @@ class SpindaRegistry:
                     UNIQUE(fingerprint, pid_hex)
                 )
             ''')
-            # Index for fast O(1)-style lookups by fingerprint
             cursor.execute('CREATE INDEX IF NOT EXISTS idx_fingerprint ON registry(fingerprint)')
             conn.commit()
 
-    def add_entry(self, fingerprint: str, pid_hex: str):
-        """Adds a new Spinda entry to the registry."""
+    def add_entry(self, fingerprint: str, pid_hex: str) -> None:
+        """Adds a new Spinda entry to the registry (idempotent)."""
         try:
             with sqlite3.connect(self.db_path) as conn:
-                cursor = conn.cursor()
-                cursor.execute(
+                conn.execute(
                     "INSERT INTO registry (fingerprint, pid_hex) VALUES (?, ?)",
-                    (fingerprint, pid_hex)
+                    (fingerprint, pid_hex),
                 )
                 conn.commit()
         except sqlite3.IntegrityError:
-            # Entry already exists
             pass
 
-    def lookup_by_fingerprint(self, fingerprint: str) -> List[str]:
+    def lookup_by_fingerprint(self, fingerprint: str) -> list[str]:
         """Returns all PIDs associated with a specific visual fingerprint."""
         with sqlite3.connect(self.db_path) as conn:
-            cursor = conn.cursor()
-            cursor.execute("SELECT pid_hex FROM registry WHERE fingerprint = ?", (fingerprint,))
-            results = cursor.fetchall()
-            return [row[0] for row in results]
+            cursor = conn.execute(
+                "SELECT pid_hex FROM registry WHERE fingerprint = ?", (fingerprint,)
+            )
+            return [row[0] for row in cursor.fetchall()]
+
 
 if __name__ == "__main__":
-    # Quick test
     reg = SpindaRegistry("data/test_registry.db")
     test_fp = "00-01-02-03-04-05-06-07"
     test_pid = "ABCDE123"
-    
     reg.add_entry(test_fp, test_pid)
     matches = reg.lookup_by_fingerprint(test_fp)
     print(f"Looked up {test_fp}, found PIDs: {matches}")
diff --git a/src/utils/resolver.py b/src/utils/resolver.py
index c250cae..9a21ac6 100644
--- a/src/utils/resolver.py
+++ b/src/utils/resolver.py
@@ -1,55 +1,66 @@
-from typing import List, Tuple
+from typing import Literal
+
 
 class SpindaResolver:
     """Mathematically resolves a visual fingerprint back to its possible PIDs."""
 
     @staticmethod
-    def coordinates_to_pid(coords: List[int], mode: str = "standard") -> str:
+    def pid_to_coords(pid_hex: str) -> list[int]:
+        """Converts an 8-char hex PID string to the 8 nibble target coordinates."""
+        p = pid_hex.lower().zfill(8)
+        return [
+            int(p[-1], 16), int(p[-2], 16),
+            int(p[-3], 16), int(p[-4], 16),
+            int(p[3],  16), int(p[2],  16),
+            int(p[1],  16), int(p[0],  16),
+        ]
+
+    @staticmethod
+    def coordinates_to_pid(coords: list[int], mode: Literal["standard", "bdsp"] = "standard") -> str:
         """
         Converts 8 grid coordinates (0-15) back to a 32-bit hex PID.
-        
+
         Standard Mapping (Rex/Little-Endian):
         Byte 0 (TL): x=coords[0], y=coords[1]
         Byte 1 (TR): x=coords[2], y=coords[3]
         Byte 2 (BL): x=coords[4], y=coords[5]
         Byte 3 (BR): x=coords[6], y=coords[7]
         """
+        if mode not in ("standard", "bdsp"):
+            raise ValueError(f"mode must be 'standard' or 'bdsp'; got {mode!r}")
+
         # Each byte = (Y << 4) | X
         bytes_list = []
         for i in range(0, 8, 2):
             x = coords[i]
-            y = coords[i+1]
-            byte = (y << 4) | x
-            bytes_list.append(byte)
+            y = coords[i + 1]
+            bytes_list.append((y << 4) | x)
 
         if mode == "bdsp":
-            # BDSP reads the bytes in reverse order (Big-Endian style)
-            # So we reverse them back
             bytes_list = bytes_list[::-1]
 
-        # Combine bytes into 32-bit integer
         pid = 0
         for i, byte in enumerate(bytes_list):
             pid |= (byte << (i * 8))
-            
+
         return f"{pid:08x}"
 
     @staticmethod
-    def resolve_fingerprint(fingerprint: str) -> dict:
+    def resolve_fingerprint(fingerprint: str) -> dict[str, str]:
         """
         Takes a fingerprint string "X1-Y1-X2-Y2-X3-Y3-X4-Y4"
         and returns both possible PIDs (Standard and BDSP).
         """
         coords = [int(c) for c in fingerprint.split("-")]
-        
         return {
             "standard": SpindaResolver.coordinates_to_pid(coords, mode="standard"),
-            "bdsp": SpindaResolver.coordinates_to_pid(coords, mode="bdsp")
+            "bdsp":     SpindaResolver.coordinates_to_pid(coords, mode="bdsp"),
         }
 
+
 if __name__ == "__main__":
     # Test with a known fingerprint
-    # PID 0x12345678 -> 
+    # PID 0x12345678 ->
     # Byte 0: 0x78 (X=8, Y=7)
     # Byte 1: 0x56 (X=6, Y=5)
     # Byte 2: 0x34 (X=4, Y=3)