High-accuracy machine learning–based colorimetric pH quantification using a custom-built portable strip-imaging device and smartphone application
摘要
Traditional colorimetric pH strips rely on subjective visual interpretation, while camera specifications and lighting variability often influence smartphone-based systems. We developed a compact, machine learning (ML)-enhanced pH sensing platform combining a custom ESP32-S3 device with controlled LED illumination and a mobile application. The system utilizes a 787-sample dataset spanning pH 0-14, extracting 45 statistical features from the red-green-blue (RGB) channels, hue-saturation-value (HSV) channels, and CIELAB color spaces. An AutoML pipeline was used to select an ExtraTreesRegressor model, achieving an