Modified Crack Detection of Sewer Conduit with Low-Resolution Images
Abstract
:1. Introduction
2. Crack Detection Procedure
2.1. Step 1: Read the Image
2.2. Step 2: Enhance the Image
2.3. Step 3: Make the Binary Image
2.4. Step 4: Fill Interior Gaps and Dilate the Crack
2.5. Step 5: Detect the Crack
2.6. Step 6: Overlay the Image
3. Crack Detection Parameters and User Algorithm
3.1. Crack Detection Parameters
3.2. User Algorithm
4. Results and Analysis
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Duration | 200 s |
---|---|
Frame Rate | 30 |
Height | 240 |
Width | 320 |
Procedures for Crack Detection | Crack Image (c18) | Non-Crack Image (n25) |
---|---|---|
Step 1 Read the Image | ||
Step 2 Enhance the Image (CLAHE: Contrast-Limited Adaptive Histogram Equalization) (Parameter: ClipLimit) | ||
Step 3 Make the Binary Image (Find the Optimum Threshold Value) (Parameter: Sensitivity and Statistic) | ||
Step 4 Fill Interior Gaps and Dilate the Crack | ||
Step 5 Detect the Crack (Complement the Image) (User Algorithm) | ||
Step 6 Overlay the Image |
Var. # | Name | Range |
---|---|---|
Var. #1 | ClipLimit | 0, 0.00001, 0.0001, 0.01, [0.1:0.1:1] {15} |
Var. #2 | Sensitivity | [0:0.1:1] (start:spacing:end) {11} |
Var. #3 | Statistic | Mean, Median, Gaussian {3} |
(a) Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.6 | 87.3 | 92.7 | 96.4 | 94.5 | 94.5 | |
0.00001 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.6 | 87.3 | 92.7 | 96.4 | 94.5 | 94.5 | |
0.0001 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.6 | 87.3 | 92.7 | 96.4 | 94.5 | 94.5 | |
0.001 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 5.5 | 78.2 | 90.9 | 96.4 | 94.5 | 94.5 | |
0.01 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 52.7 | 92.7 | 98.2 | 100.0 | 98.2 | |
0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 45.5 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 47.3 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
0.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
1.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 49.1 | 90.9 | 98.2 | 100.0 | 100.0 | |
(b) Non-Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 65.5 | 25.5 | 70.9 | 94.5 | 98.2 | |
0.00001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 65.5 | 25.5 | 70.9 | 94.5 | 98.2 | |
0.0001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 65.5 | 25.5 | 70.9 | 94.5 | 98.2 | |
0.001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 98.2 | 67.3 | 20.0 | 49.1 | 94.5 | 98.2 | |
0.01 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 70.9 | 9.1 | 10.9 | 40.0 | 72.7 | |
0.1 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 98.2 | 70.9 | 5.5 | 5.5 | 14.5 | 40.0 | |
0.2 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 72.7 | 9.1 | 5.5 | 18.2 | 43.6 | |
0.3 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 7.3 | 16.4 | 43.6 | |
0.4 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 | |
0.5 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 69.1 | 9.1 | 5.5 | 14.5 | 43.6 | |
0.6 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 | |
0.7 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 | |
0.8 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 | |
0.9 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 | |
1.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 96.4 | 70.9 | 9.1 | 5.5 | 14.5 | 43.6 |
(a) Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 49.1 | 98.2 | 94.5 | 87.3 | 83.6 | |
0.00001 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 49.1 | 98.2 | 94.5 | 87.3 | 83.6 | |
0.0001 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 49.1 | 98.2 | 94.5 | 87.3 | 83.6 | |
0.001 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 41.8 | 98.2 | 94.5 | 92.7 | 85.5 | |
0.01 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 34.5 | 96.4 | 98.2 | 100.0 | 90.9 | |
0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 90.9 | 98.2 | 100.0 | 96.4 | |
0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 27.3 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
0.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
1.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 29.1 | 92.7 | 100.0 | 100.0 | 96.4 | |
(b) Non-Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 32.7 | 90.9 | 100.0 | 100.0 | |
0.00001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 32.7 | 90.9 | 100.0 | 100.0 | |
0.0001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 32.7 | 90.9 | 100.0 | 100.0 | |
0.001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 61.8 | 21.8 | 80.0 | 100.0 | 100.0 | |
0.01 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 69.1 | 1.8 | 20.0 | 54.5 | 85.5 | |
0.1 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 7.3 | 18.2 | 40.0 | |
0.2 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 3.6 | 18.2 | 41.8 | |
0.3 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 70.9 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.4 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 70.9 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.5 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.6 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.7 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.8 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 | |
0.9 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 | |
1.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 72.7 | 3.6 | 0.0 | 18.2 | 41.8 |
(a) Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 0.0 | 0.0 | 0.0 | 0.0 | 9.1 | 34.5 | 76.4 | 90.9 | 96.4 | 98.2 | 96.4 | |
0.00001 | 0.0 | 0.0 | 0.0 | 0.0 | 9.1 | 34.5 | 76.4 | 90.9 | 96.4 | 98.2 | 96.4 | |
0.0001 | 0.0 | 0.0 | 0.0 | 0.0 | 9.1 | 34.5 | 76.4 | 90.9 | 96.4 | 98.2 | 96.4 | |
0.001 | 0.0 | 0.0 | 0.0 | 0.0 | 7.3 | 36.4 | 81.8 | 92.7 | 96.4 | 98.2 | 96.4 | |
0.01 | 0.0 | 0.0 | 0.0 | 3.6 | 10.9 | 30.9 | 63.6 | 94.5 | 98.2 | 100.0 | 98.2 | |
0.1 | 0.0 | 0.0 | 0.0 | 3.6 | 14.5 | 38.2 | 50.9 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.2 | 0.0 | 0.0 | 0.0 | 3.6 | 14.5 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.3 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.4 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.5 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.6 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.7 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.8 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
0.9 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
1.0 | 0.0 | 0.0 | 0.0 | 3.6 | 12.7 | 34.5 | 54.5 | 90.9 | 96.4 | 100.0 | 100.0 | |
(b) Non-Crack Images | ||||||||||||
Var. #2 | 0.0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | |
Var. #1 | ||||||||||||
0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 74.5 | 45.5 | 32.7 | 63.6 | 94.5 | |
0.00001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 74.5 | 45.5 | 32.7 | 63.6 | 94.5 | |
0.0001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 74.5 | 45.5 | 32.7 | 63.6 | 94.5 | |
0.001 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 | 69.1 | 50.9 | 30.9 | 56.4 | 87.3 | |
0.01 | 100.0 | 100.0 | 98.2 | 98.2 | 90.9 | 85.5 | 70.9 | 45.5 | 23.6 | 20.0 | 49.1 | |
0.1 | 100.0 | 100.0 | 100.0 | 96.4 | 94.5 | 90.9 | 60.0 | 21.8 | 9.1 | 9.1 | 29.1 | |
0.2 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 60.0 | 20.0 | 7.3 | 9.1 | 29.1 | |
0.3 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 7.3 | 25.5 | |
0.4 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
0.5 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
0.6 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
0.7 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
0.8 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
0.9 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 | |
1.0 | 100.0 | 100.0 | 100.0 | 96.4 | 96.4 | 90.9 | 63.6 | 18.2 | 3.6 | 3.6 | 25.5 |
Statistic | Mean | Median | Gaussian | |
---|---|---|---|---|
Sample | ||||
c5 | ||||
c6 | ||||
c7 | ||||
c10 | ||||
c15 | ||||
c22 |
Original Image (c1) | Image at Step 4 (c1) |
Original Image (c16) | Image at Step 4 (c16) |
Original Image (n15) | Image at Step 4 (n15) |
Original Image (n23) | Image at Step 4 (n23) |
Input: Image f(i, j) at Step 4 Output: Crack image g(i, j) (1 ≤ i≤sz(1), 1 ≤ j ≤ sz(2)) (sz(1): Height of image, sz(2): width of image) | |
---|---|
1 | Using image f(j, i) in Step 4 |
2 | for (k = 1 to No. of crack) |
3 | Truncate columns at left and right ends (which are ‘P’ in Table 8) |
4 | for (i = 1 to sz(1)) |
5 | Calculate length of cracks |
6 | end |
7 | for (j = 1 to sz(2)) |
8 | Calculate width of cracks |
9 | end |
10 | Width of cracks : longer than 3 mm (8 pixels) &, shorter than 160 pixels Length of cracks : More than 9 mm (24 pixel) |
11 | end |
Images | |
---|---|
Bad Results | c24, c52 (2 Images, 3.6%) |
Good Results | c14, c16, c23, c25, c31, c32, c39, c40, c46, c51 (10 Images, 19.2%) |
Excellent Results | Processed Image Count Excluding Upper Results (43 images, 78.2%) |
Images | |
---|---|
Bad Results | n3, n5, n30 (3 Images, 5.4%) |
Excellent Results | Processed Image Count Excluding Upper Results (52 images, 94.6%) |
Original Image and Crack Image (c1) | Original Image and Crack Image (c3) | ||
Original Image and Crack Image (c4) | Original Image and Crack Image (c7) | ||
Original Image and Crack Image (c8) | Original Image and Crack Image (c10) | ||
Original Image and Crack Image (c15) | Original Image and Crack Image (c17) | ||
Original Image and Crack Image (c20) | Original Image and Crack Image (c30) | ||
Original Image and Crack Image (c47) | Original Image and Crack Image (c48) | ||
Original Image and Crack Image (c14) | Original Image and Crack Image (c16) | ||
Original Image and Crack Image (c23) | Original Image and Crack Image (c25) | ||
Original Image and Crack Image (c31) | Original Image and Crack Image (c32) | ||
Original Image and Crack Image (c39) | Original Image and Crack Image (c40) | ||
Original Image and Crack Image (c46) | Original Image and Crack Image (c51) | ||
Original Image and Crack Image (c24) | Original Image and Crack Image (c52) | ||
Original Image and Non-Crack Image (n3) | Original Image and Non-Crack Image (n5) | ||
Original Image and Crack Image (n30) | |||
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Son, B.J.; Cho, T. Modified Crack Detection of Sewer Conduit with Low-Resolution Images. Appl. Sci. 2021, 11, 2263. https://doi.org/10.3390/app11052263
Son BJ, Cho T. Modified Crack Detection of Sewer Conduit with Low-Resolution Images. Applied Sciences. 2021; 11(5):2263. https://doi.org/10.3390/app11052263
Chicago/Turabian StyleSon, Byung Jik, and Taejun Cho. 2021. "Modified Crack Detection of Sewer Conduit with Low-Resolution Images" Applied Sciences 11, no. 5: 2263. https://doi.org/10.3390/app11052263
APA StyleSon, B. J., & Cho, T. (2021). Modified Crack Detection of Sewer Conduit with Low-Resolution Images. Applied Sciences, 11(5), 2263. https://doi.org/10.3390/app11052263