Patent ID: 8780975

Claim:
A method for adapting the throughput of a video stream comprising a plurality N of compressed images Ic n with a plurality of spatial resolutions and/or a plurality of quality layers, said images being compressed separately from one another, said method comprising at least the following steps: defining at least one key image I 0 from among the said images that the stream comprises, for each current compressed image Ic n and for each truncation point k corresponding to a spatial resolution and/or a quality layer available for this image, executing the following steps: truncating the said current compressed image Ic n at the said truncation point k so as to produce a compressed and truncated image Ic k n consuming a throughput D k n , decompressing the compressed key image Ic 0 , the current compressed image Ic n and the compressed and truncated image Ic k n , determining at least one information item regarding compensation of motion between the truncated key image I k 0 and the truncated current image I k n , applying the said motion compensation information item or items to the key image I 0 so as to obtain a reconstructed image IR n with the spatial resolution and/or quality layer of the key image I 0 , and determining an estimate of the distortion Δ k n between the reconstructed image IR n and the decompressed current image I n , determining for all the images I n of the said video stream, except for the key image or images I 0 , the optimum truncation points k n opt which minimize the sum of the distortions ∑ n = 1 N ⁢ Δ n k opt n and which comply with the following inequality ∑ n = 1 N ⁢ D n k opt n < D target - D I 0 with D target the maximum throughput that can be consumed by the video stream and D I0 , the throughput consumed by the key image or images Ic 0 , and producing a throughput-adapted compressed video stream, composed of the key image or images Ic 0 and of the compressed images truncated Ic k n at the said optimum truncation points k n opt .