Patent ID: 8879627

Claim:
A moving picture encoding apparatus comprising: an input unit configured to receive a picture to be encoded whose pixels have a first bit length; an extension conversion unit configured to convert the picture to be encoded into an extended picture whose pixels have a second bit length which is longer than the first bit length; a reduction conversion unit configured to convert a restored extended picture having the second bit length, which is generated by adding a residual signal and an extended prediction signal, into a reduced extended picture having a third bit length which is shorter than the second bit length; a storage unit that stores the reduced extended picture having the third bit length; a prediction signal generating unit configured to perform two alternative prediction modes to (i) generate the prediction signal having the second bit length and (ii) generate the prediction signal having a fourth bit length which is different from either the second or third bit length, using, as a reference picture, the reduced extended picture stored in the storage unit, and, if the generated prediction signal has the fourth bit length, convert the generated prediction signal having the fourth bit length into the extended prediction signal having the second bit length, which is subtracted from the extended picture to generate the residual signal.