发明名称 |
Two-dimensional IDCT circuit with input adder out output shifter for reducing addition operations during rounding-up |
摘要 |
The invention provides a high speed two-dimensional discrete cosine transform circuit which can reduce the number of addition operations for rounding to one time. The two-dimensional IDCT circuit calculates MxN-point two-dimensional inverse discrete cosine transforms wherein MxN is equal to 22n, and includes an MxN two-dimensional IDCT operator for calculating two-dimensional inverse discrete cosine transforms as matrix vector products of a transform matrix of MN rows and MN columns and MNth-order input vectors, a shift operator for shifting results of the calculation of the MxN two-dimensional IDCT operator rightwardly, and an adder for adding 2n-2 to a discrete cosine coefficient from among discrete cosine transform coefficients to be inputted to the MxN two-dimensional IDCT operator. An output signal of the shift operator is outputted as a circuit output signal of the two-dimensional IDCT circuit.
|
申请公布号 |
US5964824(A) |
申请公布日期 |
1999.10.12 |
申请号 |
US19970791984 |
申请日期 |
1997.01.31 |
申请人 |
NEC COPORATION |
发明人 |
MURATA, ERI;KURODA, ICHIRO |
分类号 |
H04N7/30;G06F17/14;H04N1/41;(IPC1-7):G06F17/14 |
主分类号 |
H04N7/30 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|