1. A method for generating content data for a video file, the video file comprising a video sequence and the content data for characterizing the video sequence, wherein the method comprises the steps: determining at least one face containing image by scanning at least a part of the video sequence for face containing images, each face containing image containing at least one representation of a face; generating at least one picture containing the face based on the determined at least one face containing image; cropping the at least one picture by removing an area of the picture which does not contain the representation of the face; and assigning the at least one picture to the content data of the video file, wherein the step of generating at least one picture comprises: determining for each face containing image a percentage area covered by the representation of the face, the percentage area indicating a relative amount of area of the image covered by the representation of the face as compared to an entire area of the image; and generating the at least one picture based on the determined at least one face containing image and on the corresponding percentage area.