Abstract: A method for preparing content for watermarking is disclosed. The content is available in different versions on a server for at least a client and the different versions of the content are subdivided into temporally aligned chunks. For each version of the content, candidate locations for watermarking are obtained. A watermark payload bit insertion rate is determined according to a minimum path. Watermark embedding metadata is generated for each version of the content such that the watermark payload bit insertion rate is the same. A device for implementing the method and a non-transitory program storage device are also disclosed.

Abstract: A method for determining a set of modifiable elements in a group of pictures of a coded bit-stream representative of an audio video content is disclosed. The method comprises determining a set of a candidate modifiable elements wherein a candidate modifiable element comprises a modified value of the coded bit-stream and a spatial propagation map associated with the modified value, a spatial propagation map comprising pixels whose decoding is impacted when the modified value is placed in the coded bit stream; determining a heat map for each reference frame, the heat map comprising, for each pixel of the reference frame, an information representative of the usage of said pixel for temporal prediction during the decoding of said part of the coded bit-stream coding a group of pictures; obtaining a set of modifiable elements among candidate modifiable elements, a modifiable element having a spatial propagation map that does not overlap with corresponding heat map.