train.py

from transformers import Trainer, TrainingArguments
from datasets import load_dataset
from transformers import ViTForImageClassification, ViTFeatureExtractor

# Carregar o dataset "beans"
dataset = load_dataset("beans")

# Carregar o modelo pré-treinado e definir o número de classes corretamente (3 classes para Beans)
model = ViTForImageClassification.from_pretrained(
    "google/vit-base-patch16-224-in21k",
    num_labels=3  # Beans tem 3 classes
)
feature_extractor = ViTFeatureExtractor.from_pretrained("google/vit-base-patch16-224-in21k")

# Preprocessamento
def preprocess_function(examples):
    inputs = feature_extractor(examples["image"], return_tensors="pt")  # A chave correta no Beans é "image"
    inputs["labels"] = examples["labels"]  # Certifique-se de que o rótulo está correto
    return inputs

# Aplicando o preprocessamento ao dataset
dataset = dataset.map(preprocess_function, batched=True)

# Definir os parâmetros de treinamento
training_args = TrainingArguments(
    output_dir="./results",
    evaluation_strategy="epoch",
    learning_rate=2e-5,
    per_device_train_batch_size=16,
    per_device_eval_batch_size=64,
    num_train_epochs=3,
    weight_decay=0.01,
)

trainer = Trainer(
    model=model,
    args=training_args,
    train_dataset=dataset["train"],
    eval_dataset=dataset["validation"],  # No Beans, o conjunto de teste é chamado de "validation"
)

# Treinar o modelo
trainer.train()

# Salvar o modelo e o feature extractor treinados
model.save_pretrained("./computer-vision-beans")
feature_extractor.save_pretrained("./computer-vision-beans")