Hi! could this be possible??:
I have a video showing an object that moves and I have in the engine an object that is similar to the object I’ve got in the video. Suppose that the object in the video is moving and what I want to do is to reproduce in the engine the same movements that the object does in the video. could this be possible? where could I find information about this?
Thanks and excuse my english
errrr… you want to “extract” the motion of an object seen in the video and reproduce it in the game engine?.. can you make an example of possible usage? given that, i can think better 
the only thing that comes close to what you want is matching the camera position by tracking “feature points” in the video footage (using 3rd party software). but reproducing motion of arbitrary objects sounds like heavy sophisiticated AI image processing… which isn’t integrated in blender yet
sorry if i got you wrong
marin
Yes, as if i had sensors in the object that capture its position and then map these positions in the engine.
For example I have a ball moving in a room, i video tape the ball in the room and then I model the same room and ball in the engine and want to reproduce as accurate as possible the movements of the ball.
Is there a way to “capture” from the video the position of the ball and then reproduce it in the engine?
yes, this is called motion capturing and usually used for character animation. here the movement of a real actor is mapped to a CG puppet.
motion capturing involves the use of some hardware, like 10-20 cameras (correct me if i’m wrong please) , special reflective markers placed at the actors limbs and body, and a special software that reconstructs the original motion from the pictures taken by the cameras. this is done in real-time.
i suggest you google to find out more about motion capturing methods.
I don’t need to go that far…
Just capture some positions of an object… 
Can a video be played in the game engine? can’t find about this… if i could play the video that would be a start…
there used to be a script for showing video in the GE. however even tracking the position of an object isn’t easy in general, and not possible in the game engine. it would involve feature tracking, as used by camera tracking software, which is slow and has some heavy overdeose maths.
maybe someone else knows which script enabled video playback? or just use the search button on top
Can something like this be done?:
from the video generate an animation an play the animation with some IPO actuator in the engine
You can play a video as the background image while modeling and it will change frames as you change frames in blender. I plan on using this for that same function. Using a front view and side view and using seperate videos in these views from 2 DV cameras you should be able to do some motion capture.
I planned on creating a program that tracked points frame by frame and then saved as a text file that python could import and create an IPO curve. I never completed it since I discovered you could play video in the background while modelling. Now I just track my armatures directly to the video. I believe there is a free program like this somewhere already.
thanks!!! i’ll try and i’ll tell you
excuse me this might be a silly question but how do you play a video as a background image??
That is a good question!
This past week I did the exact opposite of what aleplgr is looking for.
I made a game engine scene to get a realist tragectory and bounce of a ball. I screen capurted 70ish frames of game play and then manually mapped the frames 1 at a time to a plane which I used as a backdrop to copy the position of the ball each frame.
If anyone can post how to play a video as a background image, this process can be made much simpler in the future, thanks.
since I discovered you could play video in the background while modelling.
but how can this be done??? 
[/quote]