Cleaning Up an Image

[marco_chacon]

So--I want to take an image and simplify it to turn into a .svg so I can make it a 3d-object in Blender.

I started with this:

And used some quick erasing and threshold filters to get This:

(the other levels are even worse).

Is there a filter or technique I can use to remove / recolor "lone pixels" (i.e. a black pixel in a sea of white or vice versa)?

[Fixx]

Referring to SVG implies you would like this to become vector drawing? You will have to hand trace the building parts I am afraid.

[lacerto]

1 hour ago, Fixx said:

You will have to hand trace the building parts I am afraid.

It is also probably much faster, as it seems that you do not need to keep much of the details. Even if an advanced vectorizer could be used, it is often much less frustrating simply to trace by hand (drawing Bézier curves with the Pen Tool).

[marco_chacon]

I have Affinity Designer--but I am not too sure how to use this. Can you explain what this process would look like? I can load the PNG into Designer--but then what?

[dutchshader]

You would have to redraw (trace) the floorplan using the pen tool and shape tools.

[lacerto]

45 minutes ago, marco_chacon said:

but then what?

You would place the bitmap on the artboard, lock it (and possibly making it a bit lighter by using an image adjustment), then use the Pen Tool and start clicking the nodes to define the shapes of the underlying bitmap, considering where and when to close the shapes (this depends much on whether you need to fill them afterwards). When you get experience on this, you can basically create only the truly defining nodes and create the kinds of nodes (cusp, smooth, etc.) that are required to define the shape while you click in one go, but as Designer allows easy shaping of segments simply by dragging them, you can easily change line segments to curves. Learning to use the constraints and snapping properties (to keep lines vertical and horizontal and to get objects to align to each others) is an essential part of the process. But once learned, these kinds of tracing tasks are pretty fast to accomplish.

If you are not experienced with the Pen Tool just click around the shapes to coarsely encompass their width and height and major slopes with straight lines. Once done, drag and bend the lines to convert them to curves so that you get the shape defined more precisely and finish by dragging the control handles. If the underlying shape is not accurately enough traced, add new nodes as necessary. Often this is more efficient than trying to trace accurately (by creating right kinds of nodes at the time the nodes are created), but this of course depends on the kinds of objects that need to be traced, and the amount of experience you have on the tools that you are using.

 

 

[Fixx]

I just wonder if it were more effective to forego AD altogether in this project and use bitmap file as template directly in 3D app. Well, I do not know Blender.

[lacerto]

7 hours ago, Fixx said:

Well, I do not know Blender.

This, too, just had to be learned again, again! Isn't it crazy, there is point in asking whether the life is long enough to learn drawing with Bézier curves. Hopefully!

[Palatino]

19 hours ago, marco_chacon said:

I have Affinity Designer--but I am not too sure how to use this. Can you explain what this process would look like? I can load the PNG into Designer--but then what?

[marco_chacon]

On 10/25/2019 at 6:03 AM, Lagarto said:

It is also probably much faster, as it seems that you do not need to keep much of the details. Even if an advanced vectorizer could be used, it is often much less frustrating simply to trace by hand (drawing Bézier curves with the Pen Tool).

 

14 hours ago, Lagarto said:

This, too, just had to be learned again, again! Isn't it crazy, there is point in asking whether the life is long enough to learn drawing with Bézier curves. Hopefully!

So--I am not a Blender expert--but you can use the bit-map in the software and I may do exactly this. Blender is a great tool and you would not need to use Bezier curves to do the walls, etc.

 

On the other hand, it does have an excellent "Turn .svg into 3d object" add-on so if I could turn the image into a clean SVG with some command I'd have done that. This is a floorplan I did by hand--but it's simple compared to what I'm trying to do

[lacerto]

 

15 hours ago, marco_chacon said:

So--I am not a Blender expert--but you can use the bit-map in the software and I may do exactly this. Blender is a great tool and you would not need to use Bezier curves to do the walls, etc.

If your goal is anything like this I’d say it is a good idea to create this in Blender, right away. I just wanted to comment the huge development in the industry where advanced tools have become available for anyone, and how there is constant need to learn (again) things but only limited personal time, so in order to be efficient you can save some time by picking the right tool, and really do not need to create something like this with a pen tool! But fluent curve handling of course needs to be learned sooner or later in Blender, too, it is the ABC of creating anything in vectors even if you are not forced to draw curve elements in many projects. 

Whether you create your technical drawing primarily with Bezieres (closing them when needed), or rectangles and ellipses -- or by using mesh primitives, if you’re creating this in a 3D app -- and then shaping them, depends on the kind of drawing you need to trace, but often it is best to create the elements manually. An inaccurate bitmap is not a good starting point for automated tracing, especially as you typically need to spend some time cleaning it, and trying with different tracing settings before finding ones that produce a good starting point for the vector drawing. It is often a frustrating workflow because you end up cleaning mathematically rendered inaccuracies (e.g. removing superfluous nodes, straightening lines, aligning nodes, etc.)

 Sometimes the sensible method is simply to clean and keep the bitmap and make any necessary enhancements there (and overlay the bitmap, if necessary, with vectors and text layers), and sometimes tracing manually from the scratch. But in some cases using a tracing tool (not available in Affinity apps, though) really can produce good results in little time, but preparing the job and choosing proper settings is a specific skill, as well.

In this particular case a good approach really could be creating first a clean simple SVG file with Affinity Designer and then use the plugin to create 3D primitives.

 

[marco_chacon]

Right--I wanted a really clean SVG file to do the basic wall-plan and then I would work from there. I wanted to turn an architectural drawing into said, really clean SVG file.

Unfortunately there isn't a way to do that. 

 

By the way does Affinity Designer have a "trace" command like Inkscape does? Where I can load a graphic file and then click to convert it to a vector?

[dutchshader]

2 hours ago, marco_chacon said:

By the way does Affinity Designer have a "trace" command like Inkscape does? Where I can load a graphic file and then click to convert it to a vector

No, designer does not have that.