Comparative assessment of different image processing methods to determine the gas–liquid interfacial area in froth regimes of sandwich packings from ultrafast X-ray tomography image data

•Ultrafast X-ray tomography is used to visualize froth-like flow in parts of sandwich packings.•Gas–liquid interfaces in dynamic froth flow can be extracted by a modified level set method.•Interfacial area density decreases with increasing liquid load but is independent from gas load.