1. An apparatus comprising: an interface configured to obtain a first digital image and a second digital image; a motion definition unit configured to define a global motion vector between the first digital image and the second digital image; and a mosaic construction unit configured to combine a mosaic image from the first digital image and the second digital image utilizing the relative locations of the first and second digital images with each other as expressed by the global motion vector, wherein the motion definition unit is configured to define at least one block in the first digital image, to define for each block a search area in the second digital image, the search area being larger than the block, to map the block and its search area to an equal size, to calculate pixelwise errors between each block and its search area that are mapped to an equal size, to collect the errors into a motion register, and to define a motion between the first digital image and the second digital image by utilizing the motion register.