Abstract

Random access to arbitrary images, whether frames or fields, of a video segment compressed using both interframe and intraframe techniques may be enhanced by including state information, for decoding and display, at appropriate points in the compressed bitstream to enable random access to each intraframe compressed image. The state information may be inserted during compression or by processing the bitstream of compressed data. An image index also may be generated that maps each temporal image in a decompressed output image sequence to an offset in the compressed bitstream of the data used to decode the image. The index may be created during compression or by processing the bitstream of compressed data. To access one or more samples starting with a specified point in time in a decompressed output image sequence, the index is accessed using the specified point in time to identify another sample in the decompressed output image sequence for which data is used to produce the specified sample. The identity of the other sample is used to access the index to identify a location in the compressed data for the data used to produce the specified sample.