A method comprises receiving original encoded video stream as one input, accessing encoded data divided into slices which are further divided into blocks, receiving the list of possible changes or watermarks as another input, accessing at least one block, decoding each slice, setting down each slice, extracting from the list those changes that apply to the at least one block, and constructing propagation maps from inter-prediction or intra-prediction using changes for the at least one block. The method can further comprise decoding luminance data using the propagation maps, comparing the luminance data to a fidelity threshold, and applying possible changes or watermarks to those not exceeding the fidelity threshold.