Messages

61

General / Re: Workflow for Sketchfab Export? SSL Error on Direct Upload?

« on: February 01, 2018, 01:53:20 AM »

I'm running Windows Server 2016.  I installed OpenSSL-Light.  Still get the error.  Strangely the instructions you provided a link to say:

6) Double-clicked the EXE file: Win32OpenSSL_Light-1_0_2L
7) With SEARCH I confirmed that the two dlls were installed. On my system, these files were placed in /Windows/sysWOW64 folder. I did not have to move these files to a different location.
In browser opened my account at Sketchfab.com
9) Clicked the UPLOAD button, upper left corner of window.
10) Navigated to the folder MODEL, double-clicked "model"
11) Photoscan recognizes the presence of the doc.XML, mesh.PLY, and texture.PNG files, and
12 UPLOAD proceeds without error.

#8 and #11 don't make sense as one says "in browser" and the steps after that appear to be using upload function on sketchfab website and #11 says "Photoscan recognizes"  I think they mean Sketchfab recognizes as the function in Photo scan is File > Upload > Sketchfab > Specify info including API key -- there's no browser involved!

I still get the SSL error.  Do I need to restart Photoscan or the server?

62

General / Workflow for Sketchfab Export? SSL Error on Direct Upload?

« on: February 01, 2018, 01:19:09 AM »

But when I tried to use the Upload to Sketchfab option with API key, it failed immediately saying SSL connection unavailable or something like that.

Not sure what's going on.

63

General / Sketchfab - General Settings Guidelines?

« on: January 31, 2018, 08:14:30 PM »

I realize some setting will be dependent on the size of the model, but are there any general guidelines for Potoscan settings so that I don't produce a model that is overkill for Sketchfab but is close to the best output I can get in Sketchfab using a Sketchfab Pro Account?  I guess the main constraint is my upload can't be over 200MB unless I upgrade to get 500MB  But I'm also wondering would uploading a model with nearly 500MB in size bog down when viewing on an average consumer PC anyway, or is 500MB still pretty low and a browser with WebGL on most average computer will handle it well.

Do I just need to play around with the settings and try to get a file set close to 200MB total?  And then after some time you get a feel for what settings will get you the best quality without going over 200MB.  Although I upload as a ZIP so the fileset can actually be larger than 200MB before zip.  Ugh.. seems pretty tricky to get the optimal output.

Sorry, I guess the second part of my question is more of a Sketchfab question but just throwing it out there.

64

General / How to "Vertically Smooth" Export For Contour Map from Photoscan > QGIS?

« on: January 30, 2018, 05:11:56 AM »

We did a project of a field where they've already dug the rows so every 5 feet or so there's a 2-foot high by 3-foot wide row of dirt.  When I bring the DEM into QGIS and generate the Contour lines they are of course looking like the needle on an earthquake scale drew them as they go up and down for each row of dirt.  I want to smooth it out but wondering if that's really possible because if I reduced the resolution on the DEM so to speak, one point might be in the trough of the row and the other might be on top of the mound of the row so wouldn't the contour line be potentially 2 feet off?  Essential for each line I want the line to go through the middle halfway between the peak and the trough. 

65

General / Re: Contour Lines in DXF

« on: January 30, 2018, 02:26:12 AM »

What is the process for doing a countour map (eventually exported as DXF) if I don't want the lines spaced a fixed distance apart but I just want the lines to show elevations at ever 1 foot of elevation?

66

General / Point Cloud Density & Mesh Face Count Setting for Large Land Areas?

« on: January 27, 2018, 11:38:15 PM »

I did a 150 acre aerial survey and when I generated the point cloud I selected the Medium setting.  The survey was of a farm where they have row mounds in preparation of planting.  (Rows were about 6 feet apart) and they have little piles of dirt  on top of the mounds every 2-3 feet to hold down the tarp so there's a gazillion of these mounds.  The application is I need to generate a CAD file (DXF) for the people designing the sprinkler system so they can place the pipes and determine any significant slopes to calculate necessary water pressure.

The point cloud file was a 14GB file (I forget how many points, but there were obviously a gazillion)  This is the first type of application like this I used Photoscan for.  My gut is telling me for this type of application maybe the "Lowest" point cloud density is the best setting instead of Medium.  I think there's another similar setting when generating the Mesh. 

Now if I were making a 3D of a large sculpture, then I would guess that is where the higher number of points is desired.  Wondering if anyone out there that has used Photoscan for a similar application can recommend settings for various points of the workflow to create the most usable exports.

Thanks

67

General / Produce an Orthomosaic X feet above ground level? How Two?

« on: January 26, 2018, 12:59:12 AM »

Subject line may not be the best description of what I'm trying to do.

Basically I want to take a 3D model of a group of buildings and either remove all points above a certain elevation, or preferably take a 'slice' buy eliminating all points above and below a certain min and max elevation.  I know I would be left with no images of the tops of the buildings.  Essentially what is going on is many buildings have large roof overhangs or ground features (doorsteps, etc).  I want to estimate the dimensions of the buildings taken like 5 feet off the ground to effectively disregard the roof overhangs and the protruding features from the ground up to 5 feet.

Is this something I can do in Photoscan, or do I essentially need to bring the entire point cloud into a CAD system and perform the "slicing" there?

68

General / Re: Altitude used in Processing UAV (DJI Phantom 4 Pro)

« on: January 25, 2018, 09:31:45 AM »

Hi jazzyj,

The altitude EXIF issue of DJI UAV imagery is quite annoying.

Try one of these three 'workarounds' outlined in one of my previous posts:
http://www.agisoft.com/forum/index.php?topic=4986.msg38769#msg38769

It may be annoying but I've yet to see someone explain why it might be significantly detrimental to the accuracy of the Photoscan output.

It is widely known the barometric altitude drifts up to 3 meters over the course of the flight as the drone heats up while flying.  So towards the end of the flight the drone might think it's at 200 feet but it's actually at 190 feet.  If Photoscan used the barometric altitude, then it would negatively effect the accuracy.

I take a photo before take off and after landing.  I confirmed that even after warming the drone up the altitude drift is 1.2m based on the GPS reading.  The GPS altitude is quite accurate for measuring change in the drone's altitude.  I had a mission at 250 feet and the different in the GPS altitude before take off and immediately after reaching flight altitude was 76 meters or 249.3 feet.  The .7 foot error is probably well within the margin of error of the barometric altimeter.  But the GPS altitude won't drift like the barometric so it's actually great that Photoscan uses the GPS altitude instead of the barometric altitude (assuming I'm not overlooking some significant drawback.) 

69

General / Re: How To Dummy Down Exports? Reduce Points

« on: January 25, 2018, 07:05:00 AM »

So from my understanding the only way to reduce the points is to reprocess the dense point cloud with a different setting.  I used Medium.  This is for 4,000 photos shot at about 1inch/pixel GSD over a 250-acre area that is pretty flat (farm plot with maybe 25 feet max elevation change from lowest to highest point). 

I used that GSD because I didn't have ground control points and wanted to get the best X/Y measurement accuracy.  Now I'm just learning but it seems to me in a case where you have a very good GSD over a very large area that is fairly flat, you really shouldn't need a very dense point cloud.  The application for this project is to bring the data into a CAD system to aid in designing a sprinkler system for the land.

Am I wrong that Low would be a more appropriate setting than Medium for this type of job?

70

General / Re: Altitude used in Processing UAV (DJI Phantom 4 Pro)

« on: January 24, 2018, 10:47:26 PM »

But as far as the accuracy of the Photoscan output, does it matter that Photoscan is using Above Sea Level (ASL) instead of Above Ground Level (AGL) data as far as determining relative elevation changes in the terrain?  That's relative elevation between points in the property, not absolute elevation ASL measurements of the terrain.

71

General / How To Dummy Down Exports? Reduce Points

« on: January 24, 2018, 10:43:27 PM »

I'm testing Photoscan with a project that is 1,600 photos (about 125 acre area) and I'm needing to export for someone to use the output in CAD software (DXF).  I recently installed QGis to see how the files come in.  The 3D Model export is 500MB file size and when QGis renders it, it's of course a gazillion points.  What if I don't need that level of detail in my exports, what is the settings I need to play with to reduce the number of points in the export.  Is it the Precision setting in the export?

The point cloud export is 11GB in size!  It was processed at the Medium setting.  So do I have to go back and reprocess as a lower setting or can it be reduced in export?

To be honest, I have no idea if an 11GB point cloud file (DXF) is going to make most CAD stations choke or is that not that big?

72

General / Orthomosaic versus Orthphoto

« on: January 24, 2018, 10:33:32 PM »

I see an export option for Orthomosaic and one for Orthophoto.  What's the difference?

73

General / Altitude used in Processing UAV (DJI Phantom 4 Pro)

« on: January 24, 2018, 08:07:08 PM »

Couple basic questions.  The Beginner Workflow published for DEM / Orthophoto generation lists a step to press the button to import camera positions from EXIF data.  However when I add my photos and go to the reference pane, it already shows the GPS coordinates from the EXIF data.  So is this step not necessary then because it's doing this automatically?

I've seen various posts that the barometric altimeter on the DJI Phantom 4 drifts as the drone warms up during flight.  However the reference pane is showing altitude based on GPS measurement which is good because it doesn't have the drift.  So does Photoscan thereby not use the Above Ground Level data and therefore the drift issue is mitigated since it's using GPS elevation?

74

General / How to crop and/or display property lines?

« on: January 24, 2018, 07:58:44 PM »

I have generated a project for DEM and Orthophoto export of a field.  I didn't set any boundaries in processing so the output includes area outside the property boundary however there are features in the photo (roads, fences) I can see to easily identify the property boundary.  I'm guessing that if I wanted to add approximate property lines that would be done in the GIS or CAD software and isn't done in Photoscan?  What if I want to "crop" the output to the property boundary?  Can I still do that after processing.  It appears you can only specify a rectangular boundary and the property isn't rectangular.  So I'm guessing again it would be something you'd do in the GIS/CAD software you pull the DEM and Orthomosaic photo into?

75

General / How To Adjust Scale Using Markers?

« on: January 24, 2018, 07:29:03 PM »

I have a project with photos taken using a UAC (DJI Phantom 4 Pro) and I put control points down that I just know the relative distances between them not absolute GPS coordinates.  The published workflow for Orthomosaics and DEM doesn't cover adjusting the scale based on identifying the marker distances.  I did identify two points and create a scale but I can't seem to check the box next to the scale (or the markers) and do anything with them. Trying to figure out what steps I'm missing?