2 Implements “Seamless Branching”
DVD-Video Specification’s “Holy Grail” feature, is now
available for all DVD authoring systems
Branching", or "Seamless multi-story"; is one of the most
advanced capabilities of the DVD format. It is used to create "Director's
Cuts" of movies, for example, without having to include the same material
twice; and alternative versions with extra "buttons on video" like
the White Rabbit feature in the Matrix. And the best news is that once all
the asset preparation is done, it takes only a few minutes to perform in TFDVDEdit
The technique of seamless branching uses a special type of interleaving, somewhat
akin to multi-angle video, where multiple versions of the video are woven together
into "angle blocks", and then the bits which "aren't playing" are
skipped over during decoding/playback. However it can do far more than that.
Unlike Angle Blocks,
Interleaved Blocks used in seamless branching, with multiple
video streams interwoven, do not require the separate clips:
- Be of the same duration
- Be encoded to Mpeg 2 with Closed
GOPs and have the same GOP structure
With Interleaved Blocks:
- Video, audio, sub pictures, and
buttons on video can be completely separate and different from the other streams
that make up the same Interleaved Block, unlike with Multi-Angle.
- Each Video stream in the Interleaved
Block, can have the full compliment of up to 9 video angles*, 8 audio streams,
32 subtitle streams, separate chapters and even buttons on video; again each
different, or not even present in the other streams
in the block.
- The remote control angle, subtitle,
and audio stream change keys work only within the current assigned playing
stream in the block. The remote cannot jump to another segment/clip in
the Interleaved Block; except by navigation command (buttons on video).
This feature is available
on only the most expensive proprietary DVD authoring systems, until now.
What you can
do with this new capability
It's now possible to:
- Offer multiple seamless versions
of your show, without doubling, tripling, or even quadrupling the size of
your project. The possibilities are endless of what these multiple version
- Create seamless, 24 bit, true
"white rabbit" types of button on video appearances, with branching
off points (the jump to new content supporting the show would not be seamless)
to hidden content, that show up only if the viewer selects the feature.
- Shorter versions of the show,
i.e. highlight reels, can now be made seamless, saving precious disc space.
- Create multiple seamless versions
of menu buttons "compositing" into a stream, complete with different
transition sound tracks: menu buttons transition into the Track from scene
selection menu button activations; but are not seen when the Track plays through.
- Explore the world of Interleaved
Blocks for seamless multiple versions of the DVD's motion menus.
- Defeat DVD player out of spec
behavior that jumps Stories (left as they are normally) with the remote next
key, royally messing with Abstraction layer authoring systems programming.
- Plus many more
artistic and practical uses yet to be discovered and applied; as this
is the first time the feature is available for most creative authors and producers
since the DVD format began.
2 implements the Seamless Multi-Story Feature behind the scenes, there's NO
programming or other user intervention; it's automatic!
TFDVDEdit 2 allows this
capability with a to-be-patented method of re interleaving the VOB "after
the fact", based on “Stories” the author sets up in the Story
supporting authoring system (which makes it nice, as the various versions of
the show can be simulated non seamlessly, in advance), or the stories can be
created in TFDVDEdit 2, if the authoring system used doesn’t support the
Then, with the click
of a mouse in TFDVDEdit 2, after selecting the PGCs (stories) to be affected;
the VOB is re interleaved to make the stories seamless. This operation does
not effect DVD Studio Pro® or any other authoring systems Abstraction Layer
programming for the project in any way; everything is now made seamless, as
it should be, with the flick of a switch. Navigation, as authored, stands; just
the VOB is rearranged, you might say :-)
How it works, using
the above project schematic as an example project.
of example Project
This DVD (please see
above illustration) has a short logo intro clip that runs into two different
duration versions of the opening credits (the first Interleaved Block), then
will play into the movie.
After the movie plays
along, a single video stream with two audio and two subtitle tracks, will run
into a predetermined point which we've planned for a match frame edit of video
and audio, to "branch" into three different versions of the movie,
each of different duration. This makes up the second Interleaved Block.
All three versions have
also been edited (before encoding to Mpeg 2) to match frame the video and audio
back into the movie at the point where their duration comes to an end (in the
the "Last Part" marker).
The movie plays along
till it hits two different versions of our end credits, which make up the third
Interleaved Block of the show. The viewer has been given three menu buttons
(color coded for the example), which will take them on a soon-to-be seamless,
predetermined path through the Interleaved Blocks in the VOB.
DVD Studio Pro
DVD Studio Pro 2 is
the easiest authoring system made to create Stories in an Mpeg 2 stream; so
we'll use it in this example. Basically, the show and all it's scenes will be
lined up, end on end, on the NLE timeline and then encoded to Mpeg 2, or, Mpeg
2 sections we've pre edited and encoded (lot's of match frame editing for different
joining goes on with this feature, let me tell you!) are arranged right in DVD
Studio Pro 2 in the Track.
The show, as I've got
it lined up above, has the sections laid out in the Track, back to back, in
this order: Show Start/1st Opening credit Version/2nd Opening Credits Version/Movie
Start/Alternate Scene 1/Alternate Scene 2/Alternate Scene 3/Last Part of the
Movie/1st Ending/2nd Ending and then finally, the Movies End. As it sits, simulating
the timeline from beginning to end wouldn't make much sense, but that's all
right, at this point.
We'll make 3 Stories
to play back the three different versions of the show, so we'll need markers
placed, as shown above, to perfectly divide up the various segments.
"red Story" is shown above. This is the path that this version of
the show will take when the "red" menu button is activated.
Story" pathway through the show.
Story" pathway through the show (remember, this project example is based
on the very first illustration at the top of the page).
Once all the authoring
is done (not shown are extra markers, which you can place in the segments to
be targets of scene menu buttons, if you'd like), and the stories have been
previewed with the simulator, or in the Apple DVD Player (non seamlessly) to
make sure that's the playback behavior you want for the 3 different versions.
Stories on the disc that skip over segments of the VOB, especially on less reflective
DVD-Recordables, can take as long as a couple or so seconds to make the jump
to the next marker. Don't worry, that's about to be history.
Once you build the project
to hard drive, DVD Studio Pro® will create a VOB for this particular Track,
with the segments still end to end. Now it's time to open the VIDEO_TS folder
in TFDVDEdit 2.
The VOB is
broken up into "billions of bits" :-) and rearranged according to
DVD Spec, for players to play it back seamlessly. If a DVD player supports playing
back multiple video angles (and they all do), then it will play back the Interleaved
Block, no problem. Shown above is how the VOB is repacketized.
A feature implemented
Once in TFDVDEdit 2,
shift-select the three PGCs in the Left Pane that are the Stories, and then
right click on one of them and simply choose "Interleave". Done.
Specification routines will check the entire VOB, and make sure the bit
rate is below 7 or 8 mbps (depending on the number of streams in the particular
Interleaved Block), and a whole host of verification routines are run. The
VOB will then be repacketized; the "joins" will be re multiplexed
to add DVD Spec compliant padding of the video/audio at the
joins (about a second), and generally a flurry of activity will be going
on; as you continue to work on your project with the hundreds of other things
you can do with TFDVDEdit 2. The process runs totally
in the background, and is protected while you work on your project!
You can even import other Menu VOB's and VTS's, etc., while the process is
going on (please be sure to download TFDVDEdit
2's Program Overview to get a glimpse of what we've got here).
support site will have more information, and of course be the hot bed for
exploring this capability. Beta testing with this new feature is available
now for interested program license holders.
If you have
questions, please don't hesitate to ask them in the TFDVDEdit
Pre-Sales Support Forum.
More info on TFDVDEdit 2's capabilities found on the TFDVDEdit
2 support site
created by Trai Forrester, Larry Applegate, John Brisbin, Ernie
Brock and Robin Henson.