Messages

1

General / Indoor 3D Model Generation

« on: April 11, 2017, 03:26:08 PM »

I was testing 3D model generation with Agisoft following tutorials here - http://www.agisoft.com/index.php?id=32 and http://www.agisoft.com/index.php?id=33

I tried with close range photos of various objects and 360 degree views of buildings and the output is quite good. However, I want to now test with pictures taken in an indoor setting. We're using a robot to navigate an intricate house and we'd like to use the pictures it takes to generate a 3D model of the indoors using the photo data.

How well might this be supported by Agisoft?

2

Python and Java API / Re: Adding Ground Control Points through Python API

« on: March 30, 2017, 01:34:43 PM »

Yes, we will map the pixel location of the marker to the corresponding LLA coordinates in every picture that it is visible.

How will I need to provide this information for Agisoft to process it correctly?

3

Python and Java API / Re: Adding Ground Control Points through Python API

« on: March 30, 2017, 01:23:19 PM »

Hi Alexey. Any updates on this?

4

Python and Java API / Re: Adding Ground Control Points through Python API

« on: March 29, 2017, 11:30:26 AM »

Sorry, I should have been more clear. We can preprocess the images and identify the markers ourselves. So, I can pinpoint that some pixel location (X, Y) in image Z has geographical coordinates (Lat, Long, Alt). Having stored this information in a CSV file, does the API support importing this information and using it in processing?

5

Python and Java API / Re: Adding Ground Control Points through Python API

« on: March 29, 2017, 09:44:14 AM »

Hi Alexey. We have ~5-8 LED markers in our survey area which we can identify easily in the images. For each of these, we have  global coordinates (latitude, longitude, altitude ASL).

6

Python and Java API / Adding Ground Control Points through Python API

« on: March 27, 2017, 09:53:21 AM »

Is it possible to add Ground Control Points through the Python API? I have tried doing the same through the GUI, but cannot figure out how to do the same through the API. Is there any documentation for the same?

7

Python and Java API / Re: Focal Length Calculation

« on: March 27, 2017, 09:45:38 AM »

Hey Alexey. I just noticed something weird. I embedded the focal length information as EXIF tags (FocalLengthIn35mm) in the images in my project. I noticed that the processing time goes down noticeably. To be clear, I did not load calibration parameters as discussed here previously, just added focal length information to the EXIF. I tested this multiple times - the results are not as good as loading all calibration parameters, but the processing time is always lower.

Can you explain as to why this might be happening? Why does simply adding focal length information offer such an increase in performance?

8

Python and Java API / Re: Focal Length Calculation

« on: March 22, 2017, 01:55:57 PM »

Thanks a lot. I will try to embed the lat/long/alt information in the EXIF data and do a test run with the augmented dataset.

9

Python and Java API / Re: Focal Length Calculation

« on: March 22, 2017, 01:33:39 PM »

Hey Alexey. Can you give your opinion on the above question? What metadata will actually help in boosting performance noticeably?

10

Python and Java API / Re: Focal Length Calculation

« on: March 21, 2017, 06:16:17 PM »

Hi Alexey. You were right in mentioning that providing these parameters before hand would hardly provide any speedup. I tried it through the GUI and both took approximately the same amount of time. So, I guess there is no point pursuing this further with respect to gains in performance.

So, what extra information / metadata will actually help performance? Will adding geotags in the metadata help speed up the alignment process and, hence, improve the performance of the pipeline?

11

Python and Java API / Re: Focal Length Calculation

« on: March 21, 2017, 04:43:54 PM »

No, I haven't. Since my use case is geared towards the API usage. Why will that make a difference though?

12

Python and Java API / Re: Focal Length Calculation

« on: March 21, 2017, 04:38:32 PM »

Hi Alexey. I tried to do this comparison and followed the procedure described by you. However, when I load the saved calibration in the 2nd run, the matchPhotos / alignCameras process outputs 0 matches in tie points and consequently the process errors out. Any idea what I may be doing wrong or how to fix this?

Here is the relevant snippet of code -

Code: [Select]

doc = PhotoScan.app.document

chunk = doc.addChunk()
chunk.addPhotos(images)

...

calib = PhotoScan.Calibration()
calib.load(path_to_calibration.xml)

sensor = doc.chunk.sensors[0]
sensor.user_calib = calib
sensor.fixed = True

chunk.matchPhotos(accuracy=PhotoScan.HighestAccuracy, preselection=PhotoScan.GenericPreselection, keypoint_limit=40000, tiepoint_limit=4000)

chunk.alignCameras(adaptive_fitting=False)
...


13

Python and Java API / Re: Focal Length Calculation

« on: March 21, 2017, 11:45:57 AM »

Thanks for the guidance Alexey. But why do you think this will not provide speedup? I thought that calculating focal length and calibration parameters were an important and time-consuming step in the orthophoto generation process. I thought given this information beforehand would save considerable effort of the software. Is my understanding incorrect?

14

Python and Java API / Re: Focal Length Calculation

« on: March 21, 2017, 11:01:09 AM »

Thanks for the reply Alexey. Very helpful.

Related to this, I wanted to ask another question : In my processing, I am using the same camera over multiple projects - and the calibration parameters of the same are NOT embedded in the EXIF data of the images. I was thinking that I would let Agisoft process the first project as is and generating estimates for the calibration parameters. Then, I could embed this data into the EXIF of images used in the other projects and can potentially improve the speed of processing.

Is this a valid approach? If yes, which EXIF information should I focus on embedding within the images?

15

Python and Java API / Focal Length Calculation

« on: March 17, 2017, 12:26:30 PM »

While doing the image alignment process for generating orthophotos, I assume that Agisoft calculates the focal length internally (if it is not available in the EXIF data). Is there any way to access this calculated value of the focal length through the software API?