Agisoft Metashape

Agisoft Metashape => General => Topic started by: clardic on April 12, 2014, 07:36:59 PM

Title: Big Holes after align pictures
Post by: clardic on April 12, 2014, 07:36:59 PM

Hello
I want to make an orthophoto
All pictures are on the land of cherries. The flowers of the cherries is white.
After align photo (no problems, the pictures are aligned), but i have big holes instead my whites flowers.
How avoid the holes ?
THanks for your help

Title: Re: Big Holes after align pictures
Post by: stihl on April 12, 2014, 07:50:07 PM

What parameters did you use for alignment? Like quality and matched points limit.

Title: Re: Big Holes after align pictures
Post by: clardic on April 12, 2014, 07:59:54 PM

hi Stihl !
Precision : high
Pair selection : desactivated
Points limit : 40000 - (test with 400000 same results)

Title: Re: Big Holes after align pictures
Post by: stihl on April 12, 2014, 08:10:45 PM

Can you tell me the effective overlap in the photos by right clicking on the chunk in the workspace tab and clicking on 'show info'.

Do the holes get filled up if you enable interpolation for your mesh?

Title: Re: Big Holes after align pictures
Post by: clardic on April 12, 2014, 08:13:53 PM

the effective overlap is 2.44335

Title: Re: Big Holes after align pictures
Post by: David Cockey on April 13, 2014, 12:11:35 AM

What resolution are your original photos?

Have you tried aligning at medium rather than high setting? If so how do the results compare?

Are the images you posted of the sparse point cloud after Align, the dense point cloud after Build Dense Cloud, or the mesh? If they are of the sparse point cloud Build Dense Cloud. Build Dense Cloud will frequently fill in areas where Align does not find many points.

Title: Re: Big Holes after align pictures
Post by: clardic on April 13, 2014, 11:17:51 AM

The resolution is 24 Millions of pixels.
Yes medium has been used, no amelioration.
The image posted is a dense cloud, more than 5 millions of points.

Title: Re: Big Holes after align pictures
Post by: Bruno Andrieu on April 13, 2014, 01:20:17 PM

Hi

From my experience with plants, wind is a serious issue.
You could get missing parts for branches moving with wind;


Also, when building the mesh, try the "mild filtering" .


Bruno

Title: Re: Big Holes after align pictures
Post by: clardic on April 13, 2014, 01:44:10 PM

In this case we diden't have wind.
And  the pictures were taken at the 1/500e.
I think also that i diden't have taken enough pictures

Title: Re: Big Holes after align pictures
Post by: stihl on April 13, 2014, 07:31:16 PM

In my experience, Photoscan doens't leave any holes if you enable interpolation for your mesh generation from the dense cloud. Even though the dense cloud shows holes, if the mesh is interpolated it fills those areas up with pieces from the original imported photo's.

Title: Re: Big Holes after align pictures
Post by: clardic on April 13, 2014, 08:03:42 PM

I added 40 pictures (85 to 125).
Pictures added were with angle about 20° to the land.
The 85 are with an angle of 90° to the land.

It seems that is needed to have angle and not only pictures parallel to the land.
I have now a generation without hole. I believed to have only parallel worked.
Thanks to all