| 摘要 |
<p>PURPOSE:To attain efficient compression even to a video signal arranged in non-matrix picture elements by combining an output of a code length assignment circuit and an output of a nonlinear quantization coding circuit and outputting the result to an output terminal. CONSTITUTION:A code length estimate circuit 7 calculates a code length of a differential video image Z subject to nonlinear quantization. Since the code length is sufficiently short, a code length assignment circuit 8 allocates sufficiently much data quantity to a code word resulting from a partial video image X subject to orthogonal conversion coding. Moreover, the data quantity is allocated adaptively to the partial video image X by the code length of the differential video image Z in this constitution. Since the partial video image X inputted to an orthogonal conversion coding circuit 5 and the differential video image Z have a same number of picture elements as those of an original video signal, the compression is implemented without increasing object picture element number.</p> |
