Settings: Line detector: Minimal distance between vertical lines
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Abrimaal
Mar 8, 2018, 11:04:23 PM3/8/18
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The line detector often places multiple vertical lines on traffic signs, antennas, trees, because they are straight, but very rarely vertical.
They are easy to detect because of high contrast and they are usually detected as the first lines.
To minimize the risk of multiplication of the same error, placing lines on objects arranged at similar angle as the first detected line,
I suggest introducing a used-defined minimal distance between two lines, in the application settings.
The distance could be defined relatively, as a percentage of a single image width.
I think 5 - 10% will be good not to place vertical lines on the same thin object.
Repeating "Add vertical lines" from the panorama editor does not skip already existing lines, just duplicates them on the same objects.
If any way to define the distance already exists, could you tell me what parameter to use?
Below two examples of vertical lines placed on the same object, vertical or not
Example 1:
The detector placed the first line on the building edge and 4 lines on the same window.
It did not detect the second edge, because of bricks, what is obvious. The individual bricks are short. All together form a long straight line,
If the distance threshold was introduced, it would search for lines in the darker side of the building.
Image 2:
The detector placed 3 lines on the same antenna that is never vertical and two lines in the dark part of the building.
it did not detect the other high contrast building on the other side of the street. Because it was not parallel to the antenna?
It did not also detect the chimney that is a vertical object and very high contrast, because it already detected 5 lines.
In 60% the straightened image will be not straight.
If the distance is introduced, the probability of error will go down to 20% (1 line on the antenna). Easy to delete manually.
They are easy to detect because of high contrast and they are usually detected as the first lines.
To minimize the risk of multiplication of the same error, placing lines on objects arranged at similar angle as the first detected line,
I suggest introducing a used-defined minimal distance between two lines, in the application settings.
The distance could be defined relatively, as a percentage of a single image width.
I think 5 - 10% will be good not to place vertical lines on the same thin object.
Repeating "Add vertical lines" from the panorama editor does not skip already existing lines, just duplicates them on the same objects.
If any way to define the distance already exists, could you tell me what parameter to use?
Below two examples of vertical lines placed on the same object, vertical or not
Example 1:
The detector placed the first line on the building edge and 4 lines on the same window.
It did not detect the second edge, because of bricks, what is obvious. The individual bricks are short. All together form a long straight line,
If the distance threshold was introduced, it would search for lines in the darker side of the building.
Image 2:
The detector placed 3 lines on the same antenna that is never vertical and two lines in the dark part of the building.
it did not detect the other high contrast building on the other side of the street. Because it was not parallel to the antenna?
It did not also detect the chimney that is a vertical object and very high contrast, because it already detected 5 lines.
In 60% the straightened image will be not straight.
If the distance is introduced, the probability of error will go down to 20% (1 line on the antenna). Easy to delete manually.
T. Modes
Mar 10, 2018, 9:51:20 AM3/10/18
to hugin and other free panoramic software
Am Freitag, 9. März 2018 05:04:23 UTC+1 schrieb Abrimaal:
I suggest introducing a used-defined minimal distance between two lines, in the application settings.
I implemented an additional step to filter out lines with low distance to each other. (The limit is fixed, not user-defined.)
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