#Video-post
11 messages in this thread
I'm sure that this will result in an embarrasing pointer to the relevant
place in the manual. But I'm stuck and have to ask…..
I am using video post to combine two sets of .tga files (24bit)
The animations are identical apart from 1 object which changes.
I have frames 0-125 from the first set (0-200) in the first VP slot
I have 125-160 from the first set fading out in the second slot
I have 125-160 from the second set fading in, in the third slot
and finally 160-200 from the second set at the bottom.
The two sets sync OK.
My problem is that this does not give a crossfade, wether I go to .tgas or
to a flic the brightness ducks out drastically in the middle of what I
think should be a crossfade !
Thanks in anticipation
Grahame
oops, forgot to mention, it is all at field-rate. I do not think(?) that
is particularly relevant but maybe you know different?
Grahame
Grahame,
There doesn't seem to be much wrong with what you've done. I do
have a couple of suggestions, though:
1) Don't overlap the frames – use 0-125 then 126-159 then 160-200 and
change the .ifl list accordingly.
2) Are you using .ifl file lists? If not, you probably should and then you
can edit them with a text editor (dos5's is fine) and put the appropriate
files in that .ifl e.g.:
fila000.tga to fila125.tga in A.ifl – vp red bar 0-125
fila126.tga to fila159.tga in b.ifl – vp red bar 126-159 FadeO
filb126.tga to filb159.tga in c.ifl – vp red bar 126-159 FadeI
filb160.tga to filb200.tga in d.ifl – vp red bar 160-200
A quick way of making an .ifl file is the dos5 command:
dir fila*.tga /on /b /a-d >a.ifl
Then edit the list to add/remove entries.
This is an example that worked for me. Let me know if it works, although I
still don't see what you are doing wrong by your description.
BTW, are you doing architectural images/animations? If so, I might need
some tricks-of-the-trade info from you.
Martin
Martin
Thanks for the suggestions I will read them more carefully in the morning
and then try them out.
Almost all my work is architectural so ask away. But we will have to
whisper, don't want the competition hearing the hard bought secrets.
Grahame.
Try Martin's suggestion regarding breaking up the sequence using ifl files
into its component parts. We do this cross-fade trick between two
animations all the time and don't have any problem with it, so I'm a little
unsure of what to tell you without seeing some of your data. After trying
Martin's technique, please get back to me and let me know if you need some
more help with this.
– G
Gary will do, see reply to Martin
Mark thanks, ditto
Grahame.
Grahame-
I'm glad someone else is having the same problem. I was afraid it was my
video deck or something. I'll be very interested to see what the solution
is. I have the same problem just crossfading between 2 images. For
example, I wanted to fade between image one (A logo on a background) to
image 2 (Same logo and background with a phone # added). The effect I was
looking for was to simply have the phone # fade up. The fade was 30
frames. I tried every combination I could think of (Fading #1 out, Fading
#2 in, Fading #1 out & #2 in simultaneously), but I still got a darkening
in the middle of the fade, roughly frame 10-20. I ended up creating the
phone number against black and using alpha to fade and composite over the
same background. That seemed to work for that instance, but that doesn't
cure the problem for full screen fades. One other problem I've had is a 15
frame fade to black. It seems to be pretty choppy (the fade has noticable
steps). Have you had this happen? Like I said, I'm looking forward to the
solution on this one.
-Mark
Mark, two things:
1) Please put the image files and .prj file (including the video post
sequence) that you had trouble with together and send it to me at: Yost
Group, 3739 Balboa St. #230, SF CA 94121. I would much appreciate it.
2) Regarding your 15-frame fade to black… Remember that these are
digital (not analog) fades. When you do a digital fade, each frame is "x"
percentage of an RGB difference from the last frame. When your granularity
(# of frames) is very coarse, the percentage will be large, and thus
noticable. A 15-frame fade is about 7% difference per frame… which will
be noticable. If you want very quick fades, you're going to have to do
them with an analog video switcher in the traditional manner.
Thanks,
– G
Gary- Thanks for the info on the fade to black. That makes sense now
that I think about it. In regards to the darkening cross-fade, I think
I've found the problem. I haven't looked at it in several weeks, but it
appears that I was using Psuedo Alpha for my second image in the fade.
I've rerendered it with Queue Alpha and everything seems to be OK.
Grahamme, if your listening, make sure the two images that your fading
between are 32 bit and use the Queue Alpha in VP. Any other settings I try
(Psuedo, RGB0,0,0, or None) result in a darkening in the middle of the
fade, at least they do for me. Anyways, Gary, once again I squawked about
something that is really not a problem at all. (I've got to quit doing
this stuff at 4:00 AM.) Thanks again for the info on the fade to black.
BTW, did I miss your post on the meeting at SigGraph. I saw something
about you posting Monday A.M. but I didn't see the message.
Thanks again,
-Mark
Hey, this stuff is FAR from intuitive. The more work I do with my own
software, the more I realize how much of a mutant you've got to be to get
decent results from this stuff. But then again, if anyone could do it,
there'd be no real benefit to being a mutant. (which, fortunately for
me/us, at this point in time, there is…) Wait till you see our new
Siggraph tape. I guarantee that just the TITLES will blow you away. We've
pulled out all the stops, but it's taking a lot of work.
I'm glad you figured out that the cross-fade problem you were having is
related to using Pseudo Alpha with Queue Alpha… yup, that could
definitely do it.
And re Siggraph… there's a note I left Tuesday morning about it… but
the synopsis is that the 3DS party (note, this is not a formal gathering,
but more of a pizza and booze blow-out) is going to be from 7-9pm at the
Forum hotel, Monday night 7/27. I certainly hope to see you there, Mark!
– G
Gary- Thanks for the info on the Sigraph meeting. We rescheduled our
flights to come in on Mon. so we can attend. It will be nice just to talk
with everyone that is here on the forum, and put faces with names. We're
looking forward to seeing you again. BTW, will there be a deck for people
to play some of their stuff on at the meeting?
-Mark