Table 2 Dataset details before and after data pre-processing.

From: Advancing skin cancer diagnosis with deep learning and attention mechanisms

Class

Original image count

Augmented image count

Total image count

Class imbalance

Handling imbalance & overfitting

Actinic Keratosis

327

654

981

Low (underrepresented)

Augmented via flipping and rotation to balance the class

Basal Cell Carcinoma

514

1028

1542

Moderate

Augmentation and model regularization are applied to prevent overfitting

Dermatofibroma

115

230

345

Very Low

Increased augmentation and balanced sampling during training

Melanoma

1113

2226

3339

Moderate (overrepresented)

An augmented, weighted loss function is used to prevent overfitting

Nevus

1707

3414

5121

High (overrepresented)

Controlled sampling in mini-batches and augmentation techniques

Pigmented Benign Keratosis

1615

3230

4845

High (overrepresented)

Data augmentation and regularization are applied to reduce the overfitting risk.

Seborrheic Keratosis

1232

2464

3696

Moderate

Augmentation and class balancing strategies during model training

Squamous Cell Carcinoma

327

654

981

Low (underrepresented)

Balanced via augmentation and targeted sampling

Vascular Lesion

142

284

426

Very Low

Significant augmentation to balance class distribution

Total

8640

17,280

25,920

-

Balancing strategies used for both underrepresented and overrepresented classes