Camera Tracker Solve Failed: Not Enough Tracks – How to Fix

I’m working in Fusion and trying to use the Camera Tracker node to track a video clip, but I keep getting the following error:

Solve failed: not enough tracks Mathematically, there must be at least 8 tracks in common between consecutive frames to reconstruct the camera motion. In practice, you want a lot more than 8 (typically 150-ish) for a robust and accurate solution. You requested to solve the range [7.0, 1000.0] and there were only 2 tracks in common between frames 7.0 and 8.0.

How to Fix This?
Project file: https://drive.google.com/file/d/1POmNLC ... sp=sharing

Usually you'll have too few trackers to Solve if you increase the track filtering to a point where too many trackers are removed / ignored by the solve.
3D Camera Tracking is a process of fine tuning everything from the tracking parameters, the camera focal length (if known), and solve filtering.
It's really important to try and remove areas from the track where the movement is non-camera, and in this case you should mask out any moving traffic and people walking along the street.
If the CameraTracker locks onto those, then your solve will never be any good.
To create occlusion masks for the CameraTracker, draw and animate a polygon over the area you want to ignore and INVERT it before piping in to the Track.Mask input.
If you connect more than one polygon to mask out unwanted objects, the top poly must be set to Invert, then any others following must have their paint mode set to subtract.

I found and downloaded the footage you used from YouTube, and have solved a track for you, using the frame range in your comp. Solve result is 0.36 which is pretty good.

You can download the setup here;
https://drive.google.com/file/d/1IubHBt ... sp=sharing

From the look of it you have more than enough tracks, but if you read the message carefully it says you're trying to solve for a timerange where there are not enough tracks.
It looks like your actual shot runs from frames 133 to 241 but the camera tracker wants to solve at frame 7-8 - so something is not quite right in that sense. I don't know how that could happen in a regular workflow, but this might be part of your issue.

Video: https://drive.google.com/file/d/1fTjZ-u ... sp=sharing

It's a nice video, but what are you trying to say with this post?

How can I fix the problem and adjust which part of the video should be tracked

Then we need a little more information about your setup. I've not encountered this issue myself, so I don't know how this happened for you. Can you show some more screenshots of the various tabs in the camera tracker to help us find out what happened?