Method and device for processing an image signal of an image sensor for a vehicle

A method for processing an image signal 129 of an image sensor for a vehicle. The method comprises a step of reading the image signal from the image sensor. The image signal represents a colour measurement vector having a plurality of input measurements. The method also comprises defining weighting values ({α}) depending on the input measurements using a definition rule and a step of locating model matrices ({M}) from a plurality of stored model matrices depending on the weighting values ({α}); each of the model matrices ({M}) is generated for possible input measurements using a training rule. In addition, the method comprises creating a colour reconstruction matrix (M) using the located model matrices ({M}) and the defined weighting values ({α}) in accordance with a creation rule. And finally, a step of applying the created colour reconstruction matrix (M) to the colour measurement vector in order to generate an output colour vector representing a processed image signal 139. In the applying step, an output colour vector relating to a second colour space different to the first colour space may be generated. In the defining step, weighting values representing a non-linear division of the first colour space may be defined.