Table 2 Architecture of the proposed CNN model.

From: Smartphone-integrated portable microfluidic platform for liver biomarker quantification using deep learning

Layer type

Configuration

Function

Input

128 × 128 × 3 (RGB image)

Encoded sample image captured from the flow cell

Conv2D

32 filters, 3 × 3 kernel, ReLU activation

Detects initial color features linked to reagent-sample interactions

MaxPooling2D

2 × 2

Reduces dimensionality, retains dominant features

Conv2D

64 filters, 3 × 3 kernel, ReLU activation

Captures intermediate patterns in color variations

MaxPooling2D

2 × 2

Prevents overfitting, compresses information

Conv2D

128 filters, 3 × 3 kernel, ReLU activation

Learns high-level biomarker-specific features

MaxPooling2D

2 × 2

Further reduces noise and improves generalization

Conv2D

128 filters, 3 × 3 kernel, ReLU activation

Reinforces key differentiators for regression

MaxPooling2D

2 × 2

Balances feature complexity and efficiency

Flatten

Converts 2D feature maps into 1D input for dense layer

Dense

512 units, ReLU activation

Learns nonlinear relations between features and concentration levels

Output (Dense)

1 unit, Linear activation (regression output)

Predicts biomarker concentration from image data