Files
ASLTranslator/training.py

313 lines
7.5 KiB
Python

# ===============================
# IMPORTS
# ===============================
import os
import json
import math
import time
import pickle
import numpy as np
import pandas as pd
import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
from sklearn.model_selection import train_test_split
from sklearn.preprocessing import LabelEncoder
from multiprocessing import Pool, cpu_count
from functools import partial
# ===============================
# GPU SETUP
# ===============================
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
print(f"Using device: {device}")
if device.type == "cuda":
print("GPU:", torch.cuda.get_device_name(0))
torch.backends.cudnn.benchmark = True
# ===============================
# DATA LOADING
# ===============================
def load_kaggle_asl_data(base_path):
train_df = pd.read_csv(os.path.join(base_path, "train.csv"))
with open(os.path.join(base_path, "sign_to_prediction_index_map.json")) as f:
sign_to_idx = json.load(f)
return train_df, sign_to_idx
def extract_hand_landmarks_from_parquet(path):
df = pd.read_parquet(path)
left = df[df["type"] == "left_hand"]
right = df[df["type"] == "right_hand"]
if len(left) > 0:
hand = left
elif len(right) > 0:
hand = right
else:
return None
landmarks = []
for i in range(21):
lm = hand[hand["landmark_index"] == i]
if len(lm) == 0:
landmarks.append([0.0, 0.0, 0.0])
else:
landmarks.append([
lm["x"].mean(),
lm["y"].mean(),
lm["z"].mean()
])
return np.array(landmarks, dtype=np.float32)
def get_features(landmarks):
if landmarks is None:
return None
wrist = landmarks[0]
points = landmarks - wrist
scale = np.linalg.norm(points[9])
if scale < 1e-6:
scale = 1.0
points /= scale
mean = points.mean(axis=0)
std = points.std(axis=0) + 1e-6
points = (points - mean) / std
features = points.flatten()
tips = [4, 8, 12, 16, 20]
bases = [1, 5, 9, 13, 17]
tip_dist = []
curl = []
for b, t in zip(bases, tips):
curl.append(np.linalg.norm(points[t] - points[b]))
for i in range(len(tips) - 1):
tip_dist.append(np.linalg.norm(points[tips[i]] - points[tips[i+1]]))
return np.concatenate([features, tip_dist, curl]).astype(np.float32)
def process_row(row, base_path):
path = os.path.join(base_path, row["path"])
if not os.path.exists(path):
return None, None
try:
lm = extract_hand_landmarks_from_parquet(path)
feat = get_features(lm)
return feat, row["sign"]
except:
return None, None
# ===============================
# LOAD + PROCESS DATA
# ===============================
base_path = "asl_kaggle"
train_df, sign_to_idx = load_kaggle_asl_data(base_path)
rows = [row for _, row in train_df.iterrows()]
X, y = [], []
with Pool(cpu_count()) as pool:
func = partial(process_row, base_path=base_path)
for feat, sign in pool.map(func, rows):
if feat is not None:
X.append(feat)
y.append(sign)
X = np.array(X, dtype=np.float32)
y = np.array(y)
print("Samples:", len(X))
print("Feature dim:", X.shape[1])
# ===============================
# LABEL ENCODING
# ===============================
le = LabelEncoder()
y = le.fit_transform(y)
num_classes = len(le.classes_)
# ===============================
# SPLIT
# ===============================
X_train, X_test, y_train, y_test = train_test_split(
X, y, test_size=0.2, stratify=y, random_state=42
)
# ===============================
# DATASET
# ===============================
class ASLDataset(Dataset):
def __init__(self, X, y):
self.X = torch.tensor(X, dtype=torch.float32)
self.y = torch.tensor(y, dtype=torch.long)
def __len__(self):
return len(self.X)
def __getitem__(self, idx):
return self.X[idx], self.y[idx]
train_loader = DataLoader(
ASLDataset(X_train, y_train),
batch_size=256,
shuffle=True,
pin_memory=True
)
test_loader = DataLoader(
ASLDataset(X_test, y_test),
batch_size=256,
shuffle=False,
pin_memory=True
)
# ===============================
# MODEL (FIXED)
# ===============================
class TransformerASL(nn.Module):
def __init__(self, input_dim, num_classes):
super().__init__()
self.proj = nn.Linear(input_dim, 256)
self.norm = nn.LayerNorm(256)
encoder_layer = nn.TransformerEncoderLayer(
d_model=256,
nhead=8,
dim_feedforward=1024,
dropout=0.1,
activation="gelu",
batch_first=True,
norm_first=True
)
self.encoder = nn.TransformerEncoder(encoder_layer, num_layers=4)
self.fc1 = nn.Linear(256, 512)
self.bn1 = nn.BatchNorm1d(512)
self.drop1 = nn.Dropout(0.4)
self.fc2 = nn.Linear(512, 256)
self.bn2 = nn.BatchNorm1d(256)
self.drop2 = nn.Dropout(0.3)
self.out = nn.Linear(256, num_classes)
def forward(self, x):
x = self.proj(x)
x = self.norm(x)
x = x.unsqueeze(1) # (B, 1, 256)
x = self.encoder(x)
x = x.squeeze(1)
x = F.gelu(self.bn1(self.fc1(x)))
x = self.drop1(x)
x = F.gelu(self.bn2(self.fc2(x)))
x = self.drop2(x)
return self.out(x)
model = TransformerASL(X.shape[1], num_classes).to(device)
print("Parameters:", sum(p.numel() for p in model.parameters()))
# ===============================
# TRAINING SETUP
# ===============================
criterion = nn.CrossEntropyLoss(label_smoothing=0.1)
optimizer = optim.AdamW(model.parameters(), lr=3e-4, weight_decay=1e-4)
scheduler = optim.lr_scheduler.CosineAnnealingWarmRestarts(optimizer, 10)
# ===============================
# TRAIN / EVAL
# ===============================
def train_epoch():
model.train()
total, correct, loss_sum = 0, 0, 0
for x, y in train_loader:
x, y = x.to(device), y.to(device)
optimizer.zero_grad(set_to_none=True)
logits = model(x)
loss = criterion(logits, y)
loss.backward()
torch.nn.utils.clip_grad_norm_(model.parameters(), 1.0)
optimizer.step()
loss_sum += loss.item()
correct += (logits.argmax(1) == y).sum().item()
total += y.size(0)
return loss_sum / len(train_loader), 100 * correct / total
@torch.no_grad()
def evaluate():
model.eval()
total, correct = 0, 0
for x, y in test_loader:
x, y = x.to(device), y.to(device)
logits = model(x)
correct += (logits.argmax(1) == y).sum().item()
total += y.size(0)
return 100 * correct / total
# ===============================
# TRAIN LOOP
# ===============================
best_acc = 0
patience = 15
wait = 0
epochs = 50
for epoch in range(epochs):
loss, train_acc = train_epoch()
test_acc = evaluate()
scheduler.step()
print(f"Epoch {epoch+1}/{epochs} | "
f"Loss {loss:.4f} | "
f"Train {train_acc:.2f}% | "
f"Test {test_acc:.2f}%")
if test_acc > best_acc:
best_acc = test_acc
wait = 0
torch.save({
"model": model.state_dict(),
"label_encoder": le
}, "asl_transformer_fixed.pth")
else:
wait += 1
if wait >= patience:
print("Early stopping")
break
print("Best accuracy:", best_acc)