| 摘要 |
PURPOSE:To effectively perform mode adaptive encoding by executing a series signal processing in the case of Intra Mode, and executing a primary cosine discrete conversion only in the horizontal direction in the case of Inter Mode for which a predictive error signal is used. CONSTITUTION:As for an input signal, a difference to a predictive signal is calculated by a difference device 1, and in the input signal and a predictive error signal, a certain switching decision is executed by a switching deciding device 2 at every small block, and a signal after scanning 7 and 8 is switched by a switch 9. Subsequently, one of outputs is selected and encoded by a code allocator 10. In these signals, in the case of Intra Mode for which the input signal is used as it is, it is subjected to secondary cosine discrete conversion DCT processing by a 2d-DCT 3, and thereafter, quantized in a quantizer Q5 and subjected to variable length encoding by the code allocator 10. On the other hand, in the case of Inter Mode for which a predictive difference signal is used, the signal is subjected to primary cosine discrete conversion only in the horizontal direction by a 1d-DCT 4. A conversion coefficient comes up in a frequency order and time series order horizontally and vertically, respectively and is scanned vertically. |
