Abstract: Method for detecting an undesired object or flaw in relation to a background, wherein radiation with a first characteristic is cast by a first radiation source onto and close to the background and the location where the undesired object or flaw is to be expected, wherein radiation generated by the radiation source and reflected, dispersed, diffracted or transmitted by the undesired object is sensed by one or more radiation sensors, and wherein radiation is cast onto the location by a second radiation source with a second characteristic, which is disposed and/or has a second radiation characteristic such that apparent flaws can be removed relatively easily from the image signal sensed by the sensors.

Abstract: The present invention relates to a method for inspecting packagings for a liquid product, such as drinks, including: setting a packaging into rotation, irradiating the packaging during the rotation with a radiation of a predetermined wavelength, making at least one series of at least two recordings of at least a part of the content of the packaging during the rotation, with an image recording device suitable for making recordings at the predetermined wavelength.

Abstract: The present invention provides a method for composing a robust reference image or reference image with permissible deviation values of the exterior of a series of practically identical containers, such as bottles, crates and the like, comprising steps for: a) making an image recording of a part of the exterior of a plurality of containers from the series; b) processing the recorded image in order to obtain a first representation; c) composing a complete peripheral view of the exterior of the container on the basis of the first representations; d) determining, on the basis of all recorded images and parameters to be preset, the robust reference image of the container on the basis of which acceptable differences can be taken into account during selection of containers.