Calculating overlap of several lines in QGIS

Question

I've traced several lines that represent people's paths. Some of these lines overlap several times. I would like to get a view showing for each segment of my lines the number of line overlaps.

The methods I have used until now are:

convert the lines into points (via Qchainge plug-in) and then create a heatmaps.
using a procedure that shows the result in vector format (but very long):

Starting from the original layer "orig":

From "orig" create a layer of segments called "seg" by using Explode lines (QGIS).
From "seg" extract the center points of each segment, called "centr" using Point along lines with parameter 0.5 (QGIS).
from "centr" delete duplicates, call "centruniq" using Delete duplicate geometries (QGIS)
From "centruniq" create buffers of 50 cm called buff using Buffer (QGIS).
Run Count points analysis in polygon (QGIS) with input "buffer" and "centr", call output "count".
To "seg" element duplicates, call "seguniq" using Delete duplicate geometries (QGIS)
Join attributes from location of "seguniq" with count call final using intersects: segment vector with total number of passages attribute ("orig" elements)
style by category

I would like to ask if there was a faster solution that would allow me to display the number of line overlaps?

Perhaps these threads can help you Line width and labels based on blended values of features sharing same geometry in QGIS and Selecting features with same geometry in same shapefile. — Taras, May 04 '20 at 05:36

score 4 · Accepted Answer · answered May 04 '20 at 02:38

This may reduce the steps in the workflow.

(1) Explode lines (same as your first step)

(2) On the Exploded layer, Count the number of overlaps using an expression:

count('Explode', group_by:=geom_to_wkt($geometry))

Some use-cases will be:

(A) To set the line width:

(B) To use it for the label:

Input

Output

Calculating overlap of several lines in QGIS

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