Agricultural harvesting machine, in particular combine harvester, with a cutting mechanism designed as a harvesting attachment for cutting and picking up crop material, at least comprising - a cutting table which is assigned to the cutting mechanism and can be adjusted in its cutting table length, - a reel which is assigned to the cutting mechanism and can be adjusted in a reel vertical position and reel longitudinal position, - an inclined conveyor which is arranged downstream of the cutting mechanism and upstream of a threshing mechanism of the harvesting machine, - a driver assistance system for controlling the cutting mechanism, the driver assistance system comprising a memory for storing data and a computing device for processing the data stored in the memory, the computing device being set up to autonomously determine at least one machine parameter by means of at least one input variable and to preset it for the cutting mechanism, it being possible for the machine parameters to comprise the cutting table length and/or the reel vertical position and/or the reel longitudinal position, characterised in that means are provided which determine a crop throughput and a coefficient of vibration describing the fluctuation of the crop throughput in a region lying in front of the threshing unit, and in that the driver assistance system is set up to adapt the cutting table length from the determined vibration coefficient, the frequency components being separated by means of the computing device into a steady share and a vibration share, the coefficient of vibration being determined by means of the vibration share, and the crop throughput being determined by means of the steady share. - a cutting table which is assigned to the cutting mechanism and can be adjusted in its cutting table length, - a reel which is assigned to the cutting mechanism and can be adjusted in a reel vertical position and reel longitudinal position, - an inclined conveyor which is arranged downstream of the cutting mechanism and upstream of a threshing mechanism of the harvesting machine, - a driver assistance system for controlling the cutting mechanism, the driver assistance system comprising a memory for storing data and a computing device for processing the data stored in the memory, the computing device being set up to autonomously determine at least one machine parameter by means of at least one input variable and to preset it for the cutting mechanism, it being possible for the machine parameters to comprise the cutting table length and/or the reel vertical position and/or the reel longitudinal position, characterised in that means are provided which determine a crop throughput and a coefficient of vibration describing the fluctuation of the crop throughput in a region lying in front of the threshing unit, and in that the driver assistance system is set up to adapt the cutting table length from the determined vibration coefficient, the frequency components being separated by means of the computing device into a steady share and a vibration share, the coefficient of vibration being determined by means of the vibration share, and the crop throughput being determined by means of the steady share.