| 摘要 |
PURPOSE:To improve picture quality and to unnecessitate transfer or management for data in a quantizing table by calculating a quantizing coefficient from a frequency component data orthogonally transforming image data. CONSTITUTION:This device is composed of an orthogonal transforming means 10, quantizing means 12 and quantizing coefficient generating means 14a. Namely, encoded data Yn are generated by inputting image data Xn. In this case, a quantizing coefficient Qn used for the quantizing means 12 affects the picture quality after quantization, and it is preferable to match the quantizing coefficient to the characteristic of the image data Xn as the quantized system. Then, the quantizing coefficient generating means 14a generates the quantizing coefficient Qn by using frequency component data Fn orthogonally transforming the image data Xn. Therefore, a quantizing characteristic matched by the characteristic of the image data Xn is realized and further, transfer or management is unnecessitated for data in the quantizing table. |
