Hi

Anyone here have experience with Pix4D app for the DJI Phantom or have beta tested for the Inspire?

How well did the autonomous mapping work?

How well did the camera work when used with a photogrammetry software like Agisoft Photo Scan or Pix4D Pro Mapper?

Unfortunately the Pix4d Capture App doesn't work with the Inspire 1 (it communicates via WiFi, which the Inspire doesn't use).  I will be doing test this week to see how the Inspire 1 images work with Pix4D Pro Mapper. For  now it looks like the images will need to be captured "manually" until Waypoints are available for the Inspire 1.  In theory, it should work as long as the images have sufficient overlap for the software to determine Tie point from.  I hope to capture the Harbor Master office at the Haleiwa HI boat harbor tonight and will report back.

Did a test last night, captured ~90 photos around the harbor master building at the Haleiwa Small Boat Harbor.  The images were taken directly off the card and loaded into Pix4d (Discovery Mapper).  The image geotags weren't as good/accurate as I had hoped (it appeared that all 90 some images were only associated to only 6 different locations), but there was sufficient info in the exif header for the software to use them.  The Discovery Mapper version of the software has very limited output, but did generate a very nice looking densified point cloud (just couldn't save it as a .LAS file....).  I also own a Sensefly eBee Fixedwing UAV that came with "Postflight Terra 3D eBee software that is "powered" by Pix4D, but has a very limited list of camera models.  I had hoped I could generate a project in the Discovery Mapper software, then further process it with the Postflight software, but it wouldn't allow me to....  
So in summary, Images from the DJI Inspire 1 seem to work with Pix4D, however there is not yet an App to automate the image collection.  You need to be sure to capture plenty of images with sufficient overlap though.
Aaron.

pinpointmapping Posted at 2015-1-29 01:02
Did a test last night, captured ~90 photos around the harbor master building at the Haleiwa Small Bo ...

Thanks Aaron, much appreciated! Did all the pictures you took manually align up before rendering the point cloud? The company will according to themselves release an Inspire version soon, I hope this to be true. IHave you tried rendering your images with Agisoft Photosvan?

I have tried with Agisoft Photoscan Pro and for some reason I'm getting much distortion in the output image, I'm getting errors in depth and distorted buildings and detail. I tried at various altitudes and can't get it to work correctly yet. I have used Agisoft PS Pro with my S900/GH4 and got great results even though I had unreliable GPS geotags (tracker was not capturing points as fast as I need it to be)... I'm no expert with Photoscan, but I was able to get good results with the GH4 imagery, but nothing yet with Inspire 1...

We all are waiting and hoping
In the meantime we've be working on technique with our machine ,so far only ok results.
Pix4d folks are wait too for DJI SDK release.
Hopefully sooner than later we will get the software functionality we need to produce the deliverables we know the machine is capable of with pix4d.

hvilorio Posted at 2015-1-30 12:47
I have tried with Agisoft Photoscan Pro and for some reason I'm getting much distortion in the outpu ...

Can i ask how you got the geotag info on your GH4? The only way i've seen possible is by connecting it to your phone app and using the gps info from there which for obvious reasons won't work on a S900 due to the wifi.

We are getting excellent result using the Inspire 1 for data capture and Agisoft Photoscan for photogrammetry processing. In this photogrammetry we use the Inspire 1 to generate a 3D model of the general area and then combine it with chunks captured of details with a Nikon D810. Aligns effordlessly and the details are outstanding!

Zoomed view

neil.skypower Posted at 2015-3-7 01:03
Can i ask how you got the geotag info on your GH4? The only way i've seen possible is by connectin ...

I used a Holux RCV-3000 Wireless GPS Logger attached to my S900, and used software to add the geotag to the photos. My problem was that I didn't set the interval of the logger to match the camera, so the logger was saving GPS coordinates at a slower rate than the camera was capturing images... so I had a mismatch.

richard@oceandi Posted at 2015-3-9 02:52
We are getting excellent result using the Inspire 1 for data capture and Agisoft Photoscan for photo ...

Can you explain how you match the Inspire 1 and Nikon images? I would like to understand this better. Thanks!

Pix4D point clouds are great for our landscape and engineering departments - full capability with ortho will be even better. Autonomous flight is essential for this to ensure overlap and geotags are recorded.

Hey guys - these are some real interesting images you've posted.  I'm trying to figure out how to apply these images to work (civil engineering) and how we can help our clients but i'm struggling with how these are better than Google Earth?  If we need accurate topo information (cm accuracy) for design purposes,  then our client will either pay us to do a topo survey or they'll have lidar flown.   Other than being more recent than google, what's the other advantages or uses?

Thanks!  

djaunay Posted at 2015-3-17 09:27
Pix4D point clouds are great for our landscape and engineering departments - full capability with or ...

Was this done with the inspire?

Has anyone looked at the Maps Made Easy flight planner tool? https://www.mapsmadeeasy.com/flight_planner.
It creates a .avm mission control file which I assume can be loaded onto the Inspire 1 to do a controlled overlap flight.  I'm new to the Inspire (still in the box waiting for the weather in Eastern Canada to improve) so I'm not sure how you would load this control file so if anyone is using this tool I would love to hear the details on how the files are transferred and how well it works.

Larry

ahkim Posted at 2015-3-30 11:38
Hey guys - these are some real interesting images you've posted.  I'm trying to figure out how to ap ...

Much better/higher resolution is possible (Google Earth is only 6 inch Pixel sizes, and Pix4D has produced a pixel size of 1/2 inch.  The images can also be much more recent, and used to document change over time, with Google, you're stuck with whatever date that had it last captured.  The Images from a UAV also are captured below cloud level while Google is from a Satellite and shows clouds.  There are really a huge advantage to using your own UAV imagery, especially licensing/copyright.  Google doesn't like you to use their imagery for commercial purposes without paying, while you hold the copyright to images you capture via UAV.

pinpointmapping Posted at 2015-3-31 07:50
Much better/higher resolution is possible (Google Earth is only 6 inch Pixel sizes, and Pix4D has  ...

Great points.  Thanks for sharing.  

wlnolan: The .AWM file created by the Maps Made Easy flight planning tool is for use with the DJI 2.4 GHz Datalink and Ground Station software.  Currently, the Inspire doesn't have any ground station abilities (route planning, photogrammetry) in the app.  I would imagine it won't be long until they add it though.

We have had a lot of people free-fly with the Inspire and it has turned out great.  The Inspire camera is much better for mapping than the Vision+.  

Here is an example of the outputs you can get with an Inspire:
Inspire 1 Maps Made Easy Example

MapsMadeEasy Posted at 2015-3-31 23:52
wlnolan: The .AWM file created by the Maps Made Easy flight planning tool is for use with the DJI 2. ...

After checking the forums I suspected the Inspire lacked the ground station support but was hoping someone had a work around. The image you posted looks great, nice to see the inspire can do what I want. Do you know the altitude of the flight and the number of photos created? Curious to how many points it took to process. The image georeferencing looks quite good, was this from the geotags or were ground control points used.

Larry

Aloha Larry & others.  I found a great Excel file on Pix4D website that will help you determine the correct altitude for the desired ground sampling distance (GSD).  You can find it here....
https://support.pix4d.com/hc/en- ... GSD_Calculator.xlsx
The current geotage placed in the Inspire 1 image exif file is somewhat lacking.  It seems to round the #s a bit and produces clumps of images.  However Pix4d does a great job of making the data work and will also work with just visual content and no geotags.

I tried to work with PIX4D - I did take photos of my house, 800 photos 30 m altitude, and PIX4d gave me a pretty nice orthomosaic map and DSM. Then I did a test, where I used a lot less pictures - 120pics also 30m altitude, and pix4d generated nearly the same map.

What I want to do now is to take around 100 shots at 25, 35 and 50 meters, and in different times of the day, so all the parts of my house is well seen and there are no shadows on the generated picture.

However, I did add GCP points - 6 of them - 2cm accuracy and it produced the same results - no improvements. When I check Cameras - the point way below surface.. So I have a question for you - How do you add GCPs - I have the GCPS in degrees, but I think the height is calculated badly - I used WGS84 reference ellipsoid, maybe I need to convert it to something different - If you could help me, I would really appreciate it.

Sky

In my experience, pix4d works best when images have ~75 percent overlap (front & side, but if dealing with very complex shapes perhaps even 85%).  Adding "extra" images doesn't really "improve" the outputs as they don't add any new data, just more of the same.  The Nadir images (taken with camera pointed straight down) are used for creating the orthomosaics and you can also add oblique images  that will improve the point cloud generation/output, if you want the best output, do the alternate processing first to generate the pointcloud.  Adding GCP will only really improve the final projection/geo location of the mosaic, but doesn't realy affect the visual quality (just helps to line it up with other geospatial data).  You will improve the final output by defining surfaces like roofs or driveways etc within the Ray cloud and getting as clean of digital surface model as possible.  The DSM is used in the creation of the final orthomosaics, so by cleaning up roof and building edges etc, the final mosaic will have sharper edges as well.  Once you are happy with the resulting DSM you can load it along with just the oblique images for generating the final image and kml's etc
I recently did a project for a 50 acre farm with my inspire at roughly 30 Meters and captured ~500 images and was able to generate a final GSD of .61 inches....so capturing 800 images of just a house is a bit overkill.  While Pix4d can work with images taken at different heights, I recall a note/disclaimer that the difference in altitude should not be so much as to double the GSD.  So flying at 25 or 30 meters is ok, but the extra pass @50 meters won't be of benefit.  Aim for keeping a consistent altitude above the target/scene.  i.e.  When capturing roof, fly 25-30 meters above the roof line,but only 25-30 meters above the ground for surrounding lands.  when capturing the walls (in oblique) keep 25-30 meters away from the walls, but altitude doesn't matter much as your not capturing the ground vertical walls.  You can also improve the final output through the mosaic editor.  I've been playing with the software for about 20 months and am amazed by the outputs and possibilities.  Take some time and review the support files/documents on the pix4d website, they contain a wealth of info and are very useful.

Here we s a link to a great site that explains how the earths surface is referenced and differences between Mean sea level and elipsoidal (GPS) heights.
http://kartoweb.itc.nl/geometrics/Reference%20surfaces/body.htm

wlnolan Posted at 2015-4-1 20:22
After checking the forums I suspected the Inspire lacked the ground station support but was hoping ...

The images for that live web map were taken from about 220 ft.  That map is actually what we refer to as a Location Map which allows you to overlap multiple visits to the same location.  To get the precision needed to have the data line up nicely, we manually georeferenced each layer with a basemap and 7 control points.

If you want to the comparison between the manually aligned data and the data that was automatically aligned using the EXIF geotags, you check that out here:
Inspire 1 Manual vs Geotag georeferencing

MapsMadeEasy Posted at 2015-4-2 06:15
The images for that live web map were taken from about 220 ft.  That map is actually what we refer ...

The tractor trailer in the center of the image is about 60 feet long so that is a substantial offset with the exif camera data used for the georeferencing. I must say I expected better gps accuracy from the inspire then 60 ft or ~20 meters.

Thanks for posting the comparison.

Larry

markaguille Posted at 2015-3-30 16:51
Was this done with the inspire?

Yes Inspire1

Would a Flytrex equipped I1 help?  Is recording GPS locations twice per second.

Would a Flytrex equipped I1 help?  

offtosleep@gmai Posted at 2015-6-11 11:35
Would a Flytrex equipped I1 help?

While I don't have a flytrex, I don't think it will improving mapping results with an Inspire 1.  The phantom 2 needs the data logging because the Gopro camera isn't wired into fight controller, and is therefore not getting in GPS data for geotagging.  On the inspire, the camera is hardwire into the UAV and is geotagging the images as they are taken.  

markaguille Posted at 2015-3-30 16:51
Was this done with the inspire?

YES Inspire1 Platform

Hey guys,

If you are still waiting for Pix4D capture for Inspire we urge you to check out DroneDeploy's support for Inspire and Phantom 3.

https://blog.dronedeploy.com/dro ... a-test-a498cabb0bcb

jono@dronedeplo Posted at 2015-6-24 05:26
Hey guys,

If you are still waiting for Pix4D capture for Inspire we urge you to check out DroneDepl ...

Am I right in thinking you are the guys (Third Party) developing the Ground Station  and automated flights for and on behalf of DJI for the Inspire platform ?

Once you have completed the software, will it facilitate capturing of still images at 3 second intervals etc. or is your software to be driven by the 4K video capture?

I'm not sure which third party developer you are referring to. We are working with DJI but we are not developing any specific ground station software. DroneDeploy is separate software that helps to fly many different types of drones, including DJI, and automates the stitching of the imagery into maps/3D models.

Our software captures still images at a set rate, and 1 per 3 seconds is possible. In our software you only choose what you want to map and fly.

jono@dronedeplo Posted at 2015-6-24 08:45
I'm not sure which third party developer you are referring to. We are working with DJI but we are no ...

Jono,
Any ideas on how much the finished product will be ?  Will it accept 4K video as well as still images?

Our stitching backend currently only works with still images. What use did you have in mind for the 4K video?

Anybody have any experience using the Inspire for areas >100 acres.  I currently have 700 acres I need mapped. What's my best option?

Thanks in advance for any guidance!

daniel@gnecco.c Posted at 2015-6-26 00:38
Anybody have any experience using the Inspire for areas >100 acres.  I currently have 700 acres I ne ...

Aloha Daniel,
You need to consider/decide what Ground Sample Distance a.k.a. "Pixel size or resolution" your project requires.  Getting 1/2 Inch resolution is a lot more work than 6 inch pixel sizes.  Capturing 700 acres is really more of a job for a fixed wing platform like the 3DR Aero-M or Sensfly eBee more so than a multirotor, but it could be done with sufficient batteries & time.  Is the Area of Interest (AOI) a standard square/rectangle, or a more complex/odd shape, also what type of topography are you covering?  When capturing the images, you'll need to acquire data for areas around the perimeter of the AOI that will provide 70/80% image overlap for the full area you need captured.  Flat land is easier to capture than lands with large topographic changes.  Land Cover type also plays a roll.  Capturing areas with Forest/trees typically requires imagery with more overlap than more simple landcover types like Ag Fields or pastures.  
Good Luck,
Aaron
pinpointmapping@gmail.com

What size and type of  Ground Control Points are you guys using.  Are these always set up with a traditional theodolite to get exact GPS location or is there something else on the market to record the GPS location of temporary Ground Control Points.

GB44 Posted at 2015-8-11 06:59
What size and type of  Ground Control Points are you guys using.  Are these always set up with a tra ...

I use a Trimble handheld GNSS to get the GCP's to within about 2 cm accuracy.  Seems to work great and I just made some targets out of plywood that are about 1 square foot.

Has anyone tried the new software available on the DJI website?  I would love to try it but need to have a couple projects lined up to spend $500 on it?