Raster to vector

Descartes has the ability to vectorize aerial photographs, but you will need to set up a color mask. For example you can create a color mask including the color for the top of the buildings and then choose the vectorize tool and select the appropriate color mask. If you want to convert using the Color Mask tool, what you have to do is set the color(s) of your lines to vectorize in a mask then use this mask to vectorize. This means that the Vectorize tool will only use the lines that contain this (these) colors.....and as soon as these colors do not exist, the process will stop. The process will include some manual vectorizing and also some cleanup of the line work. Click on the widest line to get the line weight. After creating the color mask make sure Convert Line shows the color mask that you created.

Below are the steps we went through to create the color mask in Descartes.

1. In raster manager go to tools – color mask
2. In the color mask dialog right click on “temp” and select “add colors”
3. Click in empty space that makes up the background of the image that is not part of the image you wish to vectorize. Then click again to form a rectangle and all colors within this rectangle will be added to the color mask.
4. In the color mask dialog right click on “temp” and select “invert all” and all the linework you want to vectorize should highlight

If you want to convert using the Color Mask tool, what you have to do is set the color(s) of your lines to vectorize in a color mask then use this mask to vectorize. This means that the Vectorize tool will only use the lines that contain this (these) colors.....and as soon as these colors do not exist, the process will stop.

https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/f/contextcapture-descartes-pointools-forum/115047/using-descartes-to-extract-vector-outline-of-raster-data/353288#353288

https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/w/wiki/24960/new-color-masks-in-microstation-descartes-v8-cs

https://communities.bentley.com/products/geospatial/desktop/f/bentley-map-forum/108042/raster-to-vector-conversion-in-descartes/343699#343699

https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/w/wiki/24976/how-to-create-a-color-mask-and-set-multiple-colors-transparent

Thanks. I have tried to use the hilite tool. As you can see, I used it to get the roofs of the buildings. When I use the Convert area tool, I get the result in the first image, which is far from what I wanted. As you might guess, looking at the red hilites, I want to automatically get the outline (outer boundaries) of the buildings. That way I will now have the hilites represented by polygons and I can go on to add the roads. I need to use this for an area much larger than this

Hi Andrew,

The Vectorize tool can only be used to extract lines. It cannot be used to extract filled polygons.

Maybe an alternative would be to have only the outline of the polygons to be hilited, but I am not sure it is something easy to do.

HTH,

Mathieu

Hi, still can't get over this. Really disappointing. Could one of the Bentley developers take this thread further into development? Since the classification could be done successfully from the RGB, can't they enclose the areas with a polygon of the outline? It will make it even better product

Hi Andrew,

I have sent your request to product management.

Thanks,

Mathieu

Good day Mathieu, any progress on this?

Hi Andrew,

No news from product management, but honestly I don't think we will do the kind of function you are wanting soon given that our backlog for the coming months is already full.

Regards,

Mathieu

Hi Andrew,

No news from product management, but honestly I don't think we will do the kind of function you are wanting soon given that our backlog for the coming months is already full.

Regards,

Mathieu