Patent ID: 8824816

Claim:
A method for estimating a bit rate and a distortion of at least one image compressed using at least one wavelet transform operation delivering at least one sub-band b containing coefficients, said sub-band b being subdivided into at least one packet of coefficients associated with a compression quality layer, said packet also including a packet header and being transmitted through a propagation channel, said method comprising: estimating a distortion D b c caused by a compression of the coefficients of said packet; estimating a compression bit rate L b of said sub-band b; estimating a distortion D′ b c caused by corruption or loss of said packet during transmission of said packet by: equaling, if the corrupted or lost packet belongs to an enhancement quality layer, the distortion D′ b c to a distortion D b c i-1 caused by compression of a lower quality layer that is correctly transmitted, or equaling, if the corrupted or lost packet belongs to a base quality layer, the distortion D′ b c to D b ′c = D b ′ T b ⁢ T b c , where D′ b is a distortion caused by the corruption of the sub-band b, T b is a number of coefficients in the sub-band b, and T b c is a number of coefficients in block-code c of the sub-band b; estimating a sensitivity {tilde over (D)} b c of said packet according to the distortions D b c and D′ b c ; and estimating a distortion of said image caused by decompression of said packet based on the sensitivity {tilde over (D)} b c of said packet.