A number of different subroutines or algorithms are provided for locating
lost video data, reconstructing navigation data, and creating new
navigation files or the like so that the DVD may be made readable by an
ordinary DVD player. The present invention provides algorithms to recover
video data for each of a number of different DVD formats, so that video
data may be recovered regardless of which format DVD was being used at
the time (e.g., DVD+RW, DVD+R, DVD-RW, DVD-R, or the like). In addition,
the present invention provides a number of other algorithms that be used
by one or more of the different recovery algorithms, to recover various
aspects of data from a disc. The combination of these algorithms provides
a complete package of data recovery techniques that allows for video data
to be recovered in the event of a power loss or other interruption, and
in most instances, creates recordable DVD which may be subsequently read
by other DVD players and the like.