| 摘要 |
<p>PURPOSE:To efficiently perform coding without omitting high frequency components and unnecessarily degradating quantization characteristic at the time of quantization. CONSTITUTION:A quantization DCT coefficient including the DC component from a direct current component to a high frequency component is inputted to a zero detecting part 301 and a counter 303, and a quantization threshold is incremented by a quantization threshold updating part 302 when coefficient '0' is detected by a zero detecting part 301, the quantization threshold is initialized when the coefficient other than '0' is detected. Meanwhile, the counter 303 counts the quantization coefficient including coefficient '0', and in a threshold upper limit setting part 304 the upper limit of the threshold is updated in the quantization threshold update part 302 in accordance with the threshold upper limit control signal from a picture coding control part 214 and the output of the counter 303.</p> |
