Forum

Author Topic: Aling photos: SEQUENTIAL instead ESTIMATED  (Read 7895 times)

mauovernet

  • Newbie
  • *
  • Posts: 26
    • View Profile
Aling photos: SEQUENTIAL instead ESTIMATED
« on: December 23, 2023, 01:19:27 AM »
Hello:
If I am importing a video of an object, to get the photos from there.
My question is:
When aligning the photos,
is it better to select SEQUENTIAL instead of ESTIMATED?

for a better result?
thanks

tazzo

  • Full Member
  • ***
  • Posts: 162
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #1 on: December 24, 2023, 02:04:45 AM »
Depends the way you moved the camera around the object

jkova96

  • Full Member
  • ***
  • Posts: 181
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #2 on: December 24, 2023, 10:11:11 AM »
Hi mauovernet,

I definitely agree with tazzo - it depents how you move camera around object. If you move camera around object, like 360° - but around object, where your last picture approx. meet your first one, then you can choose SEQUENTIAL preselection. Also, don't know if you do (or don't) know - but you should, for SEQUENTIAL preselection, make sure that each image have different name based on image sequence...as example (img_001, img_002,...,img_nnn) or name related to date and time of capture (20231224_080800.jpg, 20231224_080900.jpg...) I think that's necessary in order to SEQUENTIAL preselection work well.

In my opinion ESTIMATED preselection works best for me.

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 15282
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #3 on: December 25, 2023, 02:41:41 PM »
Hello mauovernet,

Estimated preselection option is only possible when there is already some existing alignment (for example, obtained using Sequential preselection). So usually it may work in two steps: pre-alignment using Sequential preselection and then running alignment (with Reset Current Alignment option enabled) using Estimated preselection option. It is reasonable, if you have several overlapping lines of frames that cannot be matched with each other by Sequential preselection.
Best regards,
Alexey Pasumansky,
Agisoft LLC

jkova96

  • Full Member
  • ***
  • Posts: 181
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #4 on: December 25, 2023, 06:45:01 PM »
Hi Alexey,
Sorry for my late answer to your reply.
Yeah, but explain me this...for my graduate work - I have so much problems - missaligned images, or not ALL ALIGNED images also...
And all that when I was using SOURCE PRESELECTION, which I thought that might work as well.
To be honest with you, for mine project - preselection which I used drasticly corelates with the result I've got.
Maybe you think now...what I'm talking about, but believe me there was time when I was hopeless cause I knew that I've done good image acquisition (regarding to image quality and overlap) but software did not closed all photo sequence.
And...I was play around with these settings...so you maybe have lucky that I did not bother you with my questions much earlier.
Maybe the thing is that my object capture was church, which was so-so simmetrical.
Second thing, I thought that "SEQUENTIAL PRESELECTION" works when each picture compares to previous one if there exist overlap between them. But actually I can share one project, I hope that I have pictures for that project - I have object which is symmetrical, but I thought that around him is not so symetrical...and It did not worked with "SOURCE"...even with "SEQUENTIAL" it did not worked well. I did also apply masks, same results...unfortunatelly I don't have target object, so I cannot re-take images anymore.
If you're willing to do research, I'll try to provide data for you from these particular projects.

mauovernet

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #5 on: December 26, 2023, 12:27:38 AM »
thansk
all of you
i have ALWAYS a video ......
imported.... so
in conclusion ithink SECUENTIAL isthe best
for your answers
thanks a lot.

jkova96

  • Full Member
  • ***
  • Posts: 181
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #6 on: December 27, 2023, 11:33:53 AM »
Hi Alexey,

I know that maybe @mauovernet find solution for his task,
But I've tried to provide you data for my examples:

1.st one - when ESTIMATED preselection worked may better than SEQUENTIAL, or SOURCE as example. I don't have "problematic" images - only Agisoft Cloud link (for viewing project): https://cloud.agisoft.com/shared/projects/ef3b037d-65a9-48f3-bb49-b4c627bfaf16 From the link you can compare ESTIMATED VS SOURCE PRESELECTION, but only if you interested into it - cause I need to give you invitation link via email.

I will try to upload really "problematic" pictures later, within one week or so - If I had lucky. I mean "problematic" when talking about differences between SEQUENTUAL VS SOURCE preselection.


2.nd project - in which I thought that maybe SEQUENTIAL will work BEST but nothing...either SOURCE, ESTIMATED or SEQUENTIAL did NOT CLOSE created image loop. For this example, I have photos used in project available via this link - https://mega.nz/folder/Z0RhhSAS#dBg40DUJQImhqKn6i84X9Q

So, my task for you - at least for 2.nd one will be: Try to get 36 aligned out of 36 images used for capturing object. Images are not huge, maybe 12 MP for each one.

Best regards! :)

J.K.

tazzo

  • Full Member
  • ***
  • Posts: 162
    • View Profile
Re: Aling photos: SEQUENTIAL instead ESTIMATED
« Reply #7 on: December 27, 2023, 03:06:27 PM »
In the 2nd project you have floor reflections and people walking and moving.. at some point somebody is touching the lego thing  ;D

You have to manually mask all images if you want to use them. Many point of view are missing.. you won't get anything good with that dataset.

Quick suggestion to randomly scan objects: try to move closer, if the whole object is not captured at once doesn't matter, better to have more photo with an higher fill-rate. If the fill-rate is low and environment is changing, you have a problem.
« Last Edit: December 27, 2023, 04:17:57 PM by tazzo »