Long Distance Small Motion Sequence

[weizhe...@gmail.com]

Hi,

I try to use COLMAP to get the depth map of image sequence (video frames) taken by UAV camera, while no intrinsic parameters are known. The scene is crowded people near some buildings and it is generally far away from the camera. 

I first try automatic reconstruction with command like:

/src/exe/automatic_reconstructor \
    --workspace_path $PROJECT_PATH \ 

    --image_path $PROJECT_PATH/images \

    -- single_camera 1

but the performance is bad, so I try to put more control and do it step by step like use sequential_matcher rather than exhaustive_matcher since the sequence is from continuous frames in a video. But the performance is also not good. 

Therefore, I want to know is there any thing I should do in order to get good performance with such long distance, small motion , continuous video sequence?

Here is the sequence: https://www.dropbox.com/sh/3ii3tqb18dgdtd6/AAAK0PAwWuj-Ts3_R70wrWhca?dl=0

Thank you for your help!

  

[weizhe...@gmail.com]

The link should be : https://www.dropbox.com/s/s3ulmavicy3g03r/seq1.zip?dl=0

  

[Johannes Schönberger]

Can you try the option `--data_type=video`?

[weizhe...@gmail.com]

Thank you for your quick response!

I tried, but no much difference. What I did is put all the image frames in a folder using the frame order, then use the option  --data_type=video with the auto_recontruction command , but no much difference....

[Johannes Schönberger]

Did you try to downsample the video? Often a too high frame rate can make the results worse with the default parameters.

> --
> You received this message because you are subscribed to the Google Groups "COLMAP" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to colmap+un...@googlegroups.com.
> To post to this group, send email to col...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/colmap/e20d7ca3-ce95-47a7-8275-f51b2a95fe28%40googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.

[weizhe...@gmail.com]

Thank you for your suggestion. I tried down sample the frame rate , however, it doesn't help. One interesting thing is that the depth seems to be reversed(down sample or not), the close one is bigger than the remote object. 

It works fine with COLMAP example images , for me. the problem is really strange...

Thanks :)