摘要 |
A system and method for compression of video data uses digital processors to transform the data to a more compressed format. After preprocessing, a KL (Karhunan-Loève) transform is used to treat an array of pixels as a series of vectors transformed to a new set of basis vectors selected so that the data vectors (now represented by coordinates with respect to the transformed axes) lie closest to the transformed axes. A number of the axes lying closest to the data is selected, and the vectors are projected onto the subspace spanned by those axes. Those components extending into the orthogonal subspace are retained as a separate (second) data set, and a second GS ("Gram-Schmidt) compression is applied to those components. By suppressing portions of the data generated in the GS transformation, lossy transformations are efficiently accomplished. The data may also be preprocessed and where different parameter values may be selected for the pre-processing, the system may be tried for different parameter values and the result with the lowest entropy selected.
|