HP Labs Technical Reports

A Fast Algorithm for DCT Domain Filtering

Merhav, Neri; Bhaskaran, Vasudev

HPL-95-56

Keyword(s): : DCT-domain filtering; data compression

Abstract: A method is developed and proposed to efficiently implement spatial domain filtering directly on compressed digital video and images in the discrete cosine transform (DCT) domain. It is demonstrated that the computational complexity of this method is significantly smaller than that of the straightforward approach, of converting back to the uncompressed domain, convolving in the spatial domain, and retransforming to the DCT domain. It is assumed that the impulse response of the two dimensional filter is symmetric and separable. The method is applicable to any DCT-based data compression standard, such as JPEG, MPEG, and H.261.

Back to Index