[Oberon] backwards playing video with WMPlayer, MPEG, DivX ?

Thomas Frey thomas.frey at alumni.ethz.ch
Sat Feb 10 03:02:04 MET 2007

The decoding of DivX and mpeg depends on previous frames. Once in a
while there is a so-called key-frame in the video stream that does not
depend on other frames. To play a movie backwards, the images between
two key-frames need to be stored and displayed in reverse order. This
is very memory intensive. Alternatively only a fixed number of frames
can be stored, but then more than one frame per frame needs to be
decoded because decoding always has to start at a key frame and all
frames from there the the desired frame need to be decoded, otherwise
among others the motion compensation fails.(the color space
transformation can be left out to save some time) .

To your previous question: There is no VOB demultiplexer for
bluebottle. It should not be too complicated, but nobody has done it.
(Even if there was a demultiplexer, only Code-Free DVDs could be
played unless somebody implements the DeCSS hack to break the
country-code nuisance)


On 2/10/07, Patrick.Hunziker at unibas.ch <Patrick.Hunziker at unibas.ch> wrote:
> Is there a simple way to play parts of a mpeg and divx video in bluebottle
> backwards ?
> Thanks
> Patrick
> ----------------------------------------------------------------
> This message was sent using IMP, the Internet Messaging Program.
> --
> Oberon at lists.inf.ethz.ch mailing list for ETH Oberon and related systems
> https://lists.inf.ethz.ch/mailman/listinfo/oberon

More information about the Oberon mailing list