Enlargement and reduction of image/video via discrete cosine transform pair, part 1: novel three-dimensional discrete cosine transform and enlargement

bstract. We propose novel matrix-form representations of the onventional forward three-dimensional (3-D) discrete cosine transorm (DCT) and the inverse 3-D DCT. The pair of the computationlly efficient 3-D DCTs causes the formulation to be more concise ith a systematic structure, which has a high potential for the develpment of other applications via the 3-D DCT pair. Applications for nlargement of image/video implemented by the DCT pair are also resented. These new algorithms effectively eliminate ripple and locky effects and maintain the original characteristic. Moreover, ue to the essentially even-function property of the DCT, the proosed enlargement of an image demonstrates the desired symmetic property. As a result, they can also find numerous applications in mage processing and video coding. Simulation results show that roposed mechanisms enable good performance for scaling algoithms of sequences, images, and videos, as expected. © 2007 SPIE nd IS&T. DOI: 10.1117/1.2804710