4 Point Bilinear Track - Reset graphic with offsets

Hi Everyone,

I have a 4 point track. I have to use a very small part of the image for the track. The graphic on the bilinear is now small. How do I set the offsets so the graphic is the original proportional size?

I remember a technique for this, (I can’t remember exactly how to do it) that involved doing the 4 point track, only saving one frame of keyframes, changing a setting to edit offsets, reloading that saved single frame track, and then reloading the entire track again in the track mode.

Does this sound familiar? I don’t see an edit offsets pulldown in the Vertices tracker.

Maybe there is an easier way to do this now?

Thanks in advance,

Andrew

Look up bilinear UV and vertices.

Youre searching for the correspondences between a vertex and its uv coordinate

thank you for the direction. I did the 4 point track in the vertices tab. saved that. also deleted all but the last frame of key frames. saved that as setup_lastframe. reloaded the original track with all the keyframes in the vertices tab. went into the uv points tab and loaded the setup_lastframe track. exited that and the graphic is back to it’s normal size and position. great to have this documented. thanks again!

There are also “To UV” and “To Vertices” buttons that will speed that up for you!

If you hit F8 with your surface selected, you’ll get the UV view (purple mesh). Adjust that by scaling the UV verts down to scale the graphic back up.

I knew it, of course there are. Thanks, I’m looking into this now.

It also kinda sounds like you want the perspective to be correct which you can do by using ‘perspective’ instead of ‘bilinear’ in the Surface Type option.

Yep

Similar rules apply

Subtly different outcomes

Subtly different capabilities

Personally I’m a big fan of 3d track, object track and planar track

But with a different toolset form borisfx (Syntheyes)

Which is irrelevant since the initial ask was about bilinears in action

Since the introduction of the perspective surface type I have not touched bilinear since most of what we do requires to be perspectively correct.

Basically the only thing I use a bilinear for is when I need to mirror out an edge for a few pixels using the crop.

dont forget this tool too. Quite useful.