Hi all,
I’m an experienced user in Blender and have been trying to figure out an issue I’m having with Icarus (and Voodoo) for that matter.
I’m using
Blender 2.42 and Icarus 2.09.
The problem I’m having is after doing all of the necessary steps the tracking data in Icarus is great, I choose a origin point for my object, adjust ground plane etc. I put a primitive in at that point to test the data. matches perfectly.
Now I import the data into Blender and sequence up the scene. I render and the object is floating and sliding all over the place.
Using Voodoo I get the same good tracking results, add in a primitive still looks good until I get it into Blender and then the same thing happens.
I also get the same results whether it’s Freemove or Tripod.
I’m totally out of possible solutions, at least in my mind.
All of my video footage is 720 x 480, 29.97fps and DV NTSC D1 0.9 pixel. And is maintained through the entire process. Pretty standard I’m guessing.
Any input will be greatly appreciated
3Deviant,
I know that this is not much help me saying this, but Icarus import works fine for me! :eyebrowlift2:
As far as my workflow goes, I…
check that the camera settings match my camera
choose ‘tilt, pan and turn’ (or whatever it is) if it’s on a tripod
make a matte around any objects that fill a large proportion of the screen
make some user features on very obvious distinctive features
make the axes at at least two frames
add an origin point
hit track + calibrate
maybe bundle adjust if the skew etc are a bit wobbly
export into human readable format
import into Blender using the script from here (create curves)
I don’t bother with adding a primitive or anything, I just stay in calibration mode. You should be able to see from calibration mode, after calibrating, that the features stick very well to the background and the plane moves realistically.
I usually manage to get the camera axes the wrong way round, so I move the IPO curves from Icarus to dRotX, dRotY, dRotZ and add an offset in RotX, RotY and RotZ.
And it all works fine - this was with something green-screened, so there were very few features on the background to work on, and it did it fine!
Anyway, I know there’s no real guidance in this post, but me writing my workflow may help you see a step you’ve missed or something. 
I found this interesting, and I’m curious because on some failures it’s as if the object moves before the background does and sometimes the object moves in the same direction of the camera slightly but scaled, which to me would be an axis or two inverted???
Could you explain this more, it’s worh it for me to look into it.
Well basically I found, especially as the videos I was using had no real sense of axes that you could tell, that my x/y/z didn’t really point in the right direction. Of course, I could have moved everything else but that gets complicated if they’re animated - instead it’s easier to move the camer by some offset.
As far as I can tell, RotX and dRotX are basically additive, but you can only I->Set Frame for RotX. So I moved the camera’s RotX, RotY and RotZ IPO curves that had been imported from Icarus to dRotX, dRotY, dRotZ, and deleted the originals. After that, I set my video as the background picture (videos as backgrounds in 2.43, yay!), and by rotating and moving the camera, could get it to a point where the two lined up. Make sure to get the perspective right.
As far as that, there’s not much I can think of. Understand that my camera movements were always correct relative to the camera - just pointing in the wrong direction.
Hope that helps. :evilgrin:
One thing that I’ve come across in the past is that if you’re only tracking within a certain starting frame other than 1 (e.g. frames 134-157), then when you import back into blender, the actuall proper tracked stuff will only start when you move to frame 134 or something.
I don’t think this sounds like the problem you’re having, but it could be!
Well my camera is pointed in the right direction all the time, and everything is starting on the right frame together. Is the camera lens data extremely critical (1/4", 1/3" ccd etc.?) I’ve tried different ones and they aren’t really that different, the same bad result is similar. I shoot my video with a Canon ZR400. Maybe it has a horrible lens distortion that I have to correct? I might try and roll the ground plane 180 degrees on different axis to see if it’s exporting the data for one axis backwards (not because it’s wrong, but because it’s only doing what I tell it too)
If I can’t get it too work, could I send a short clip to one of you and have you run it through it’s paces? Just to compare methods and results. I’m about ready to give up. I’ve got a few 5-10 minute movies completely created and rendered in Blender but I can’t get 5 seconds of video to track correctly;-( go figure:eek:
Sure, give it a go! Upload it to savefile or something like that if it’s huge, but I have an enormously fast connection so don’t worry about it at my end.
I’ll try and toss it up here tomorrow if I can’t beat it into submission tonight!
Now I’m really puzzled. After experimenting last night I found that converting everything to 720 x 576 PAL 25 fps pixel 1.067 footage works really really good. The video looks a little squished but the tracking is flawless. I’d like to try my standard NTSC DV1 footage (720x480 29.97 .9 pixel) but just change to 25 fps and see if that is a factor.
Peculiar. Though it would of course be better to keep it in NTSC format for quality’s sake.
Sudden thought - have you made sure you’ve changed the frame rate to 30 (nearest to NTSC you can get) in BOTH Blender and Icarus? I imagine that Icarus stores data per frame, so if the frame timings don’t match up, once you’ve imported it the camera data will be aligned with the wrong time. Perhaps… :eyebrowlift2:
I actually key in 29.97 on the third tab of the camera parameters, although it still says 30 fps on the main preview window. The raw footage is captured at 29.97 and exported at that. And rendering out of Blender in Quicktime format .mov I select the 29.97 from the codec settings. Is it possible that it is really doing 30fps from Icarus instead of 29.97? Would it make that big of a difference? Well in a 200 frame segment it would be off by 6 frames in the end?
Yes, unfortunately Blender only works in integer frames/s. However, if you have both Icarus and Blender set to 30, it shouldn’t make a difference. Yes, it will be out by a few frames towards the end compared to what it would be, and this may be a problem if you are syncing sound to your video, but it should not have any effect on the tracking.
I’ll PM’d you my email address if you want to send the stuff you have at the mo, and I’ll see if I can see anything obvious!
Haven’t heard back in awhile? I think I did find the problem as you stated, Blender doesn’t support 29.97 fps. I guess I didn’t know that. When I pull down the codec for avi’s and movs it has a choice for 29.97, but maybe it’s a bug. I converted everything to 30 fps and it works great!
Yeah, sorry, 3Deviant, I’ve been somewhat busy and when I do get a chance to work on it Icarus crashes… maybe sometime soon I may be able to get it to work!