Encoding video images using foreground/background segmentation

摘要

Blocks of video images are characterized as being part of either scene foreground or background for encoding. The foreground/background segmentation analysis involves a pixel level and a block level. During the pixel level, interframe differences corresponding to each original image are thresholded to generate an initial pixel-level mask. A first morphological filter is applied to the initial pixel-level mask to generate a filtered pixel-level mask. During the block level, the filtered pixel-level mask is thresholded to generate an initial block-level mask. A second morphological filter is preferably applied to the initial block-level mask to generate a filtered block-level mask. Each element of the filtered block-level mask indicates whether the corresponding block of the original image is part of the foreground or background. In a preferred embodiment, both morphological filters filter out isolated mask elements.