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dan
1st December 2002, 09:41
Hello all....

Is the following because of my methodology or the DVD standard?

In Scenarist, I've set up and imported a sequence of bitmaps with a script with the plan of using them as buttons. The areas of the bitmaps that is to be used for the buttons doesn't change location on the screen, but changes with each frame. [The *planned* end result is that the animated subpictures sit over the full color video, and are a close-to-sepia tone version of each frame, so that when the user moves the cursor over the video, the reduced color version of the frame [the subpicture] changes from 100% to 0% opacity. It's gimmicky, but, in my opinion, it looks pretty cool. To get it to work, I adjusted highlight colors and button areas, and it previews just fine. To take care of the transparency of each frame of the subpicture, I changed the duration of the highlight layer to match that of the subpicture [and also of the background video file].

Though it simulates just fine, when I try to add it to a title in the Scenario Editor, I get:
"Error - No valid Sub-Picture exists for highlight 01:00:00:00 in Track(scene1-t) Sub-Picture stream 1." I tried adjusting the highlight length down at various intervals until it was 2 frames long, but I still got the same error. I'm using 4:3 panscan menus, and I have both the wide and panscan subpictures in place, so it's not, as far as I know, something "simple".

I was messing around, trying to get it to work, and came across the fact that if the duration of one instance of the highlight layer matches the duration of one instance of the subpicture [in my case, 1 frame], it imports just fine. Now, I don't want to have to define a highlight layer [6 buttons] for each frame of 18 seconds of video [18s * 30frames/s * 2 [button areas for [I]both panscan and wide]= no fun], but I figured I could sacrifice an afternoon pursuing this to make it work. But, luckily, I did some more testing before sitting down to do all the button defining. When I had the highlight layer respectively defined for two consecutive frames, I imported the track into the Scenario Editor with no problems, and I wanted to preview my hard work [all two frames' worth] in a regular video player program, so I went to make a disc image, but no...Scenarist wasn't having any of that. I got an error telling me that there wasn't enough time between when one highlight ends and the next begins. I adjusted to see where the limit was, and I got to about 7 or 8 and decided I had better things to do with my time [granted, I ended up wasting the time I saved, but that's beside the point]. I'd assume that the the minimum is probably 10 [it's a nice number] or 15 [half of 30fps], but if that's so, the effect looks more like bad authoring than, dare-I-say, innovative [personally, I've never seen this particular trick for chapter selection done before...as animated subpictures are rare in and of themselves...but, of course, there may be a reason that I've never seen it before (i.e. the technical restrictions of the standard)].

Regardless, any help would be appreciated.
[for what it's worth, there are alternate [read: easier] ways to get this effect, but, out of principle, I'd rather not setup a series of menus that use auto-action buttons to "secretly" move to another menu video that looks the same except for one area...[again, in my opinion] waiting for the set-top to reseat the laser whenever the cursor is moved is no fun to sit through...]

Boiled down:
Does trying to set the length of the highlight layer to last the entire range of subpicture frames go against Scenarist and the DVD standard? Having the highlight layer redefined every frame definitely seems "against the rules".


Thanks in advance...
Dan

jk2
1st December 2002, 17:42
I have managed to make some animated buttons.

The buttons are static in postition, but pulsate (in size) - giving the effect of being "alive". - Similar to a beating heart as it contracts and expands.

If the buttons don't actually move around the frame, its easy to solve the "No valid subpicture exists for this highlight" problem. Just copy the 1st highlight and paste it all along the track until you have enough :) (provided the subpics are continuous)

The real problem is that Highlights cannot exist for a small duration ie: 1 frame only - hence does not support all desired animation frame rates and each time a highlight is pasted , the button command is not pasted with it. So you would have to connect them all manually.

A work around for this, is to export a scenarist script (.scp) file, locate the region that corresponds to the buttons/commands and do a mulitple replacement in a good text editor.

What is really needed is a program to parse the .scp file, and let you copy a button command from the 1st hightlight/subpic across all the subpicture stops.

www.mindtrap.co.uk

dan
1st December 2002, 19:36
Thanks for the response...

Dragging the highlight layer for the desired duration was something I tried, and it didn't work.

This how I have it set-up...
[I adjusted the final length to be so short to make things simpler...]

8 continuous frames of background video starting at 01:00:00:00
8 sequential frames of subpicture starting at 01:00:00:00
One highlight layer starting at 01:00:00:00 with a duration of 8 frames.
[Simply, they all start and end at the same time.]

I still got the same error [No valid Sub-Picture exists for highlight 01:00:00:00 in Track(scene1-t) Sub-Picture stream X.] when I tried to import the track into the Scenario editor; is there something you're doing differently than I?

For what it's worth, I'm not sure if editing an .scp file would enable the highlight layer to move along with the subpictures...though the correct buttons could be defined for each frame and it would preview just fine in Simulation mode, you'll probably get the error that basically says that there isn't enough time between when one highlight ends and the next begins. [provided you're trying to define the highlight at every subpicture frame]. Of course, I may be wrong, so I'm willing to eat my words, but I only said the above because, in my experience, Scenarist won't let highlights start so near to one another.

Thanks,
Dan

jerzy
13th December 2002, 00:52
I had the some problem.
It seems to me there is a bug in Scenarist v2.
It doesnt collect right information for preview (only for subpicture).
Try to create dvd.
There is no more error mesage and dvd plays fine, exactly as you wanted.

dan
13th December 2002, 10:55
Thanks for the response, and I mean no offense, but I'm not sure what you mean.

I tinkered within Scenarist some more, and managed to make it work in as desired in the preview window by simply setting the initial [at time=0] one frame long highlight. Scenarist previewed it just fine, and I had high hopes, and made a disc image, but both PowerDVD and WinDVD only displayed the highlight for that first frame, so I think that it previewed just fine might be a bug in Scenarist.

If I try to create a disc image with the highlight layer defined for each frame of subpicture [29.97frames/sec], I get an error about the time between highlight layers being too short when I go to make the disc image. The error message stops the process entirely.

I think the problem with setting the duration of the highlight to last throughout the aniamted subpictures' complete duration violates the DVD standard. I think that if a highlight layer is present, it needs to be defined individually for each subpicture. This method [of having many short subpictures and one long highlight stream] definitely would violate that rule. [If I'm wrong about that part of the standard, don't hesitate to tell me, anyone. I won't be offended or anything; it's just my (sort of) educated guess.]

So, jerzy, if you could, please explain more thoroughly.

Thanks a lot,
Dan

jerzy
16th December 2002, 02:05
I'm sorry i wasnt clear.
My replay refered to message:"Error - No valid Sub-Picture exists for highlight 01:00:00:00 in Track(scene1-t) Sub-Picture stream 1."
This is definitely bug in Scenarist.
I hope thats help you.