| 摘要 |
<p>PURPOSE:To reduce the amount of code generation by inserting zeros in the places where a certain amount of zero coefficients continuously appear in the quantized coefficients and the coefficients which come after these coefficients are assumed to have no effect. CONSTITUTION:The picture data compression device is provided with a block conversion means 102 dividing picture signal into two dimensional blocks of NXN (N is an integer) picture elements, a difference means 103 taking a difference between the block signal and the picture signal which is one frame prior one, an orthogonal transformation means 105 orthogonally transforming the difference block signals and outputting the transformation coefficients, a quantization means 106 quantizing the transformation coefficients and outputting the quantized coefficients and a variable length coding means 108 making the quantized coefficients into variable length coding. And zero coefficient discrimination means 107 checks the values of the coefficients for zero or non-zero in the direction from the lower frequency components to the higher frequency components for all NXN coefficients which are the outputs of the quantization means 106, makes all zero coefficients, if zero coefficients continuously appear for n numbers and outputs them. Thus, the degradation of picture quality is prevented and a reduction of the amount of code generation is realized.</p> |
