Computationally fast wavelet-based video coding scheme
Ayan Sengupta, Michael L. Hilton, Bjorn D. Jawerth · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1994
We present a new technique for rapidly evaluating the inverse wavelet transform in video compression applications. The wavelet transform decomposes each pixel in an image into a linear combination of basis functions. Typically, very few pixels in a video sequence change from one image to the next; therefore, very few of the coefficients in the transformed video sequence change from one image to the next. We capitalize on this fact, and speed up the reconstruction of transformed image sequences by computing the inverse transform for only those coefficients that have changed since the previous image. Our prototype software-only video decompressor based on this idea is capable of reconstructing 256 by 256, 8-bits per pixel, greyscale images at a rate of 18 frames per second at a compression ratio of about 22:1.