Fast scheme for downsampling and upsampling in the DCT domain

Rakesh Dugad, Narendra Ahuja

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Given a video frame or image in terms of its 8×8 block-DCT coefficients we wish to obtain a downsized or upsized (by factor of two) version of this frame also in terms of 8×8 block-DCT coefficients. We propose an algorithm for achieving this directly in the DCT domain which is computationally much faster, produces visually sharper images and gives significant improvements in PSNR (typically 4 dB better) compared to other compressed domain methods based on bilinear interpolation. The downsampling and upsampling schemes combined together preserve all the low-frequency DCT coefficients of the original image. This implies tremendous savings for coding the difference between the original (unsampled image) and its prediction (the upsampled image). This is desirable for many applications based on scalable encoding of video.

Original languageEnglish (US)
Title of host publicationIEEE International Conference on Image Processing
Number of pages5
StatePublished - 1999
EventInternational Conference on Image Processing (ICIP'99) - Kobe, Jpn
Duration: Oct 24 1999Oct 28 1999


OtherInternational Conference on Image Processing (ICIP'99)
CityKobe, Jpn

ASJC Scopus subject areas

  • Computer Vision and Pattern Recognition
  • Hardware and Architecture
  • Electrical and Electronic Engineering


Dive into the research topics of 'Fast scheme for downsampling and upsampling in the DCT domain'. Together they form a unique fingerprint.

Cite this