1. A stereo camera device comprising: a plurality of picture image taking sections; and at least one processor comprising: a processing area setting up section which sets up a plurality of image areas to be processed and a reduction ratio of an image based on a driving environment of a vehicle on which the stereo camera device is mounted; an image correction section which makes a correction of picture images taken; a parallax calculating section which calculates parallax, an amount of dislocation between a left image and a right image, based on the corrected picture images; and an image recognition section which carries out image recognition processing for each image area in order to recognize objects; wherein: when the plurality of image areas are set up, the image recognition section is adapted to perform the image recognition processing according to a first mode for at least one of the image areas and a second mode for the remaining image areas; in the first mode, the image recognition processing is based on left and right images of the corrected picture images and the calculated parallax in order to recognize objects and to calculate a three-dimensional position of the recognized objects; and in the second mode, the image recognition processing is based on the left and the right images of the corrected picture images in order to only recognize objects.