Geotif Not Importing Correctly

[kstenson]

I am using AutoCAD Map 3D 2024 and I'm having issues with importing mosaic files created from our drone flights.  It doesn't happen with every flight but sometimes the imported image will appear like tiles from the mosaic are out of order or have bars of color, and when you zoom in will get all pixelated.  The mosaic files are created with pix4dmatic, and range in size from 50-150MB.  The images appear fine when viewed in Windows Photo Viewer or QGIS.  I am using mapiinsert to bring the images into my drawing.

Thanks

Kelvin

[ChicagoLooper]

Hi @kstenson 

Thanks for the screenshots but your issue can't be diagnosed with just your uploads.  

Would it be possible to upload the actual tile(s) for troubleshooting?

If you're dealing with drone captured imagery, MAPIINSERT command, although popular, is not the way to add them to your drawing.

[kstenson]

Attached is the mosaic I'm currently having issue's with.  I know I mentioned a out of order tiled look, but we don't actually export tiles from pix4dmatic, although I do believe that is an option, we just have it export a single merged geotif.

Thanks

[ChicagoLooper]

@kstenson 

Genesee Lake, correct?

TS Rd 502 & RR 24.

[kstenson]

That is the correct area yes.

[ChicagoLooper · Accepted solution]

@kstenson 

It's the shape of the image. AutoCAD can't handle the jagged edges. It throws off the the way the image is geolocated. The un-squareness throws off the way AutoCAD interprets the arrangement of pixels. AutoCAD likes squares and rectangles. If you use any other shape than square or rectangle you're at risk of getting funky stuff when you insert. Squares/rectangles insure consistent pixel rows and pixel columns.

I did this:

1. I cropped the image in another program (Global Mapper) to a rectangle (refer to blue rectangle in image-1.)

Image-1

2. Since Global Mapper is a GIS program, the image's projection (coordinate system) is re-calculated and re-applied to the cropped image. Back in Cad, I use a Feature Data Object (FDO) connection, as opposed to MAPIINSERT, to add the image to modelspace. An FDO is more versatile than using MAPIINSERT because it can easily perform coordinate transformations. Use MAPCONNECT to get the Data connect palette.

<<BTW, using an FDO connection is capable of combining multiple images into a single image and is just as qualified, or better, than other programs.>>

 Click the Connect button.

Image-2

3. After clicking 'connect' button, verify the parameters of your connection, then click Add To Map button.

Image-3

[kstenson]

ChicagoLooper, thank you for your help.  I think I can crop the image in QGIS, I'm sure I've done that in the past.

I'll reach out to pix4D as well to see if there are ways within the software to export a more rectangular mosaic, we have just recently started using pix4Dmatic and it does make a more jagged photo compared to pix4Dmapper, which we had been using before.

I'll also look at if it can export tiles and look at using FDO to import to combine them, might make my flight processing a little faster as well since it won't need to create the large mosaic.

[ChicagoLooper]

@kstenson 

Continuing with the program mentioned in post #6, I can also use Global Mapper to export the image without any cropping. When I perform the export, GloMap gets rid of the jagged edges and turns the funky shape into a rectangle. Here's the way GloMap exported image. The image is still georeferenced accurately so it still inserts correctly..

GloMap added white stuff to make it a rectangle during its export operation! The extra white stuff isn't ideal but if you're only zooming-in to the middle parts and you're far enough away from the edges, then this type of export might work for you.

[Pointdump]

Hi Kelvin,
Welcome to the Autodesk Forums.
In addition to excellent advice from @ChicagoLooper, you can re-save your tiff in QGIS to JP2 format. Then you can use MAPIINSERT even with the jaggies.
Dave