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Messages - WSurvey

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General / nm
« on: May 23, 2020, 07:40:08 AM »

General / Yaw, Pitch & Roll values for horizontal photos
« on: May 18, 2020, 12:03:32 PM »

I have pictures taken from an imaging total station. I am importing reference values for these photos including camera coordinates and orientations. To my mind Yaw = azimuth/bearing, Pitch = (180°-zenith angle) and Roll = o°. This makes sense to me, but Metashape disagrees. When I align photos with these initial values and a known marker in the scene, Metashape tells me that my Yaw, Pitch and Roll values are in error. the Yaw and Roll values are supposedly in error by almost 180°, suggesting I'm facing the wrong way, but the calculated coordinates of any marker I place in the scene are correct.

Any ideas?


General / Re: How to force image alignment?
« on: May 16, 2020, 05:41:25 PM »
Hello WSurvey,

Import Cameras option is designed to import precisely known exterior and interior information data.

To load the data that you have mentioned, you should use Import CSV button on the Reference pane toolbar.

Thanks Alexey,

In my estimation of angular values, would I be right in using bearing/azimuth as yaw, pitch as angle upwards from straight down, and roll as 0 in my case as the total station camera is always level?

General / How to force image alignment?
« on: May 16, 2020, 10:40:13 AM »

I have some images taken from an imaging total station. The exif data contains no position information, but I know the camera coordinates and image angles perfectly. Can I enforce these values on Metashape and make the project proceed as if the images are aligned using the values I give it? I tried importing the image reference data from CSV but Metashape doesn't want any of it, and displays no coordinates for my cameras.

In short I need to impose my own 'align camera' result on Metashape in order to proceed any further.

I know each image's: roll, pitch, yaw, projection centre XYZ. When I try 'Import Cameras' function it doesn't look like I have a simple option to import X Y Z R P Y for each camera in a CSV format. It's just manufacturer specific file types. I'd like to use s simple CSV if I could.


General / Re: Exporting Orthomosiac
« on: December 01, 2019, 01:39:54 PM »
Thank you mate.

All of the above seems ok, I think maybe it has to do with the CAD package reading the TIF but not reading the associated TFW file?

I can input the TFW corrections in manually when I import them into CAD, though I'm not sure what all the parameters for each field are.

The easting and northing are obvious, though the others I don't know.

? = 0.0276442
? = 0
? = 0
? = -0.0276442
Easting = 659419.784772277
Northing = 7712026.76188448

Would you be able to help me out with what the first 4 parameters in the TFW file stand for SAV?

Thanks again for any help you can provide.


TFW parameters:

Pixel width component in E direction
Pixel width component in N direction
Pixel height component in E direction
Pixel height component in N direction
E coordinate of centre of top left pixel
N coordinate of centre of top left pixel

General / Re: Workflow to process the Photography of "PHANTOM 4 RTK"
« on: September 08, 2019, 09:12:23 AM »
Hello xabierr,

For general cases we do not suggest to optimize (and actually use) p3 and p4 coefficients. THis recommendation is based on our experience with various project types and user's feedback.

My experience now with a few Phantom 4 Pro/Adv cameras is that they have some quickly changing radial lens distortions that need P3 and P4 solved for in order to best model them. Also the alignment process seems more accurate when tested against PPK if the corners of the photos are masked out from keypoint detection. It is my opinion that nothing good comes from these corners of P4P JPGs.


Has anyone seen this behavior with this particular lens or have an explanation as to what is happening?


How many radial distortion parameters are you using? if you are only solving for a couple of parameters then this might just be the best fit. What does your residual plot look like?

General / Re: Is External GPU an good way to increase performance?
« on: June 28, 2019, 03:03:19 PM »

Hi Alexey,

If Metashape is performing a GPU accelerated operation, am I right in thinking that as long as the CPU is able to feed the GPU fast enough to keep it at 100% utilization, then a CPU beyond that speed will make little difference to the time taken in that step?

General / Re: Is External GPU an good way to increase performance?
« on: June 25, 2019, 11:44:46 AM »
Hello WSurvey,

For image matching and depth maps calculation higher number of CUDA cores and higher frequency means better performance. For build mesh from depth maps (although some sub-steps are still CPU only) and refine mesh operations amount of VRAM is also important and would have effect on the performance.

Alexey, another question. If Metashape is performing a GPU accelerated operation, am I right in thinking that as long as the CPU is able to feed the GPU fast enough to keep it at 100% utilization, then a CPU beyond that speed will make little difference to the time taken in that step?

Hello WSurvey,

In Metashape you can solve this task by importing point shapes to a separate shape layer, then in the Ortho view mode select all shapes of the imported layer, use Update Altitudes option for the selection and then export the shapes.

Update altitude would write Z value of the DEM under XY coordinates for every shape vertex.

Thank you Alexey.

Thank you Alex. Failing an Agisoft solution I will use the QGIS plugin you mention.

General / How do I extract DEM elevations at specific coordinates?
« on: June 18, 2019, 01:35:24 PM »

Given a text  file of E,N or X,Y or Lat,Long horizontal coordinates, is there any way to automatically extract the DEM elevations at these locations? Perhaps a way to import points and set them on the DEM and export again?


General / Re: Is External GPU an good way to increase performance?
« on: May 29, 2019, 04:04:33 PM »
Hello ChrisC,

I think it mostly depends on the GPU performance (number of CUDA cores / shader processor units) and the data transfer band between computer and external card.

We have not so much experience with particular external GPU devices, but have quite good results with the docker stations (for example, ROG 2) that are able to use almost any kind of modern GPU devices, however, such docker stations are mostly focusing on the gamer class cards.

Hello Alexey,

IS there any specification of a GPU that correlates most strongly to performance when processing in metashape?

e.g. CUDA cores, GPU clock speed, GPU memory?

I'm wondering if there was a systematic way to maximise dollar-for-performance when buying a GPU.


Feature Requests / Centre of weight detection for placing or moving markers
« on: February 16, 2019, 08:58:54 AM »
It sure would please me to be able to place or move targets to the calculated centre of weight of a white-on-black or black-on-white dot. Drawing a circle around the region then have the software add or move a marker to the centre would be a bonus for situations where automatic detection just won’t cut it.

Or even better a snap-type of mode could be enabled whereby if a marker is moved then it snaps to the greyscale centre of mass of the surrounding 4, 9, 16 or whatever amount of cells you specify as a tolerance.

Feature Requests / Re: Background Map
« on: November 12, 2018, 01:12:30 PM »

and ...

Web Map Services

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