A method for adjusting image data defining an image, the method comprising: decoding the image data; (i) generating a saliency map once for a scene of the decoded image data, the scene comprising a plurality of frames of the decoded image data; wherein generating the saliency map comprises obtaining metadata specifying one or more special areas within the image and setting the special areas to have increased saliency in the saliency map; (ii) establishing a global transformation based on the scene of the decoded image data wherein establishing the global transformation comprises ignoring parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency or weighing parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency less heavily than other parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having higher saliency; and (iii) applying the global transformation to the scene of the decoded image data, wherein steps (i), (ii) and (iii) are repeated once for another scene of the decoded image data, the another scene comprising a plurality of frames of the decoded image data. decoding the image data; (i) generating a saliency map once for a scene of the decoded image data, the scene comprising a plurality of frames of the decoded image data; wherein generating the saliency map comprises obtaining metadata specifying one or more special areas within the image and setting the special areas to have increased saliency in the saliency map; (ii) establishing a global transformation based on the scene of the decoded image data wherein establishing the global transformation comprises ignoring parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency or weighing parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency less heavily than other parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having higher saliency; and (iii) applying the global transformation to the scene of the decoded image data, (i) generating a saliency map once for a scene of the decoded image data, the scene comprising a plurality of frames of the decoded image data; wherein generating the saliency map comprises obtaining metadata specifying one or more special areas within the image and setting the special areas to have increased saliency in the saliency map; (ii) establishing a global transformation based on the scene of the decoded image data wherein establishing the global transformation comprises ignoring parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency or weighing parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having low saliency less heavily than other parts of the scene of the decoded image data corresponding to image areas indicated by the saliency map as having higher saliency; and (iii) applying the global transformation to the scene of the decoded image data, wherein steps (i), (ii) and (iii) are repeated once for another scene of the decoded image data, the another scene comprising a plurality of frames of the decoded image data.