Title :
Direct N-point DCT computation from three adjacent N/3-point DCT coefficients
Author :
Soo-Chang Pei ; Meng-Ping Kao
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan
Abstract :
An efficient method for computing a length-N Discrete Cosine Transform (DCT) from three consecutive length-N/3 DCTs is proposed. This method differs from previous ones in that it reduces considerable 31-38% arithmetic operations and uses only length-N/3 DCTs instead of length-N DCTs. We also find its great applications in fractional scaling of a block DCT-based image by the factor of 1/2/sup /spl alpha//3/sup /spl beta//. This would be very useful in high-definition television (HDTV) standard, whose display size is usually 16:9. The comparison with conventional methods is provided.
Keywords :
discrete cosine transforms; high definition television; image processing; DSP; HDTV; block DCT-based image; direct N-point DCT computation; fractional scaling; high-definition television standard; Arithmetic; Digital signal processing; Discrete cosine transforms; Displays; HDTV; Interpolation; Signal processing algorithms; TV; Transform coding; Video compression; Direct DCT domain computation; fast DCT; radix-3 DCT;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2004.840868
