Abstract: A system and method for rapid selection and viewing of video programs in digital video broadcasting are disclosed. In one example of the invention, a parser sorts the data stream from different video programs and the sorted data are then stored in a fast cache memory. There are at least two intra-coded frames per video program available for decoding in the cache memory, constituting at least one group of pictures. Upon selecting a video program, a decoder decodes data starting from the oldest intra-coded frame in the cache memory. Full motion video and accompanying audio of the new video program are therefore available immediately resulting in a seamless and aesthetically pleasing transition between video programs. Multiple decoders are used in other aspects of the invention to provide thumbnail videos of a group of video programs for visual program selection.

Abstract: An apparatus and method for image data compression performs a modified zero-tree coding on a range of image bit plane values from the largest to a defined smaller value, and a vector quantizer codes the remaining values and lossless coding is performed on the results of the two coding steps. The defined smaller value can be adjusted iteratively to meet a preselected compressed image size criterion or to meet a predefined level of image quality, as determined by any suitable metric. If the image to be compressed is in RGB color space, the apparatus converts the RGB image to a less redundant color space before commencing further processing.

Abstract: A wavelet pyramid-based still-image and video compression apparatus uses line-vectors, context-dependent quantization thresholds, hierarchical tree-structured displacement coding, synchronous prediction, and conditional zerotree branch updates to improve intra- and inter-frame coding speed and efficiency, and to improve video stream noise resilience. The disclosed intra-frame coding methods can be used to improve the coding efficiency of wavelet-based still-image compression algorithms.

Abstract: An apparatus and method for image data compression performs a modified zero-tree coding on a range of absolute image values from the largest to a determined smaller absolute value, based upon file size or quality. If it is desired to maintain more detail in the image, then a vector quantizer codes the remaining values below this determined smaller value to zero, and lossless entropy coding is performed on the results of the two coding steps. The determined smaller value can be adjusted by examination of the histogram of the tree, or iteratively to meet a preselected compressed image size criterion or to meet a predefined level of image quality, as determined by any suitable metric. If the image to be compressed is in RGB color space, the apparatus converts the RGB image to a less redundant color space before commencing further processing.