The invention relates to an endoscopic image processing system, which includes an optical digital camera, in particular having great depth of field, and means which, in the detection range of the optical digital camera, generate distance information which is processed together with the image information and is then detected and used in order to generate additional geometric data relating to the image content. The measurement information is obtained from an image of an auxiliary instrument which may be designed as a normal surgical instrument, wherein the image of a section of the auxiliary instrument is extracted from the camera image and serves as a reference parameter for the image scale. On this basis a piece of geometric information is then inserted, true to scale and in fixed relation to the auxiliary instrument, into the current camera image as a virtual measuring or display element. Said element can be an image scale, for example, which appears suspended on the auxiliary instrument in the image and can be “operated” therewith.