Camera Tampering: An unauthorized or an accidental change in the view of a surveillance camera is called a tampering. This can be the result of a natural phenomenon or it can be induced to accomplish malicious activities. Figure 1 (a) & (b) shows an example of tampering due to a natural phenomenon, where the sunlight is reflected on to the camera lens. Figure 1 (c) & (d) shows anexample of tampering induced by a hu- man. The perpetrator blocks the view of the camera using a cardboard. Images Figure 1 (b) & (d) are compromised and may not be useful for surveillance. Another example is of natural tampering would be when cameras switch between day/night mode. Often cameras fail to auto-focus correctly after switching between day/night mode resulting in a defocussed view.Examples of unauthorized tampering would include spray painting the lens, changing the viewpoint intentionally to accomplish malicious activities (such as theft and property damage).
Most literature has classified camera tampering as covered, defocussed, and moved. Covered tampering occurs when the view of the camera is blocked. Spray painting the lens, blocking it with hand, and accumulation of dust, spider webs, and droplets are exam- ples of covered tampering. Defocussed tampering occurs when the view of the camera is blurred. Formation of fog on lens, failures to focus, and intentionally changing the focus are examples of defocussed tampering. Moved tamper- ing occurs when the view point of the camera has changed. This can occur as a result of strong wind, an intentionally change in the direction of the lens with malicious intent.
UHCTD is a large scale synthetic dataset for camera tampering detection. The dataset is created from two outdoor surveillance cameras, Camera A and Camera B, the viewpoints fore each are shown in Figure 2 Row 1. Camera A has a resolution of 2048X1536, and Camera B has a resolution of 1280X960.The videos are cropped to a 3 rd of their resolution during synthesis. Camera A has a framerate of 3 frames per second (fps), and Camera B has a framerate of 10 fps. The two cameras together capture a wide variety of regular scene changes that occur in surveillance cameras.
We define four classes: normal, covered, defocussed, and moved. The tampers are synthesised into the videos using image processing techniquies.
Please cite the paper
Mantini, P., Shah, S. K. (2019, September). UHCTD: A
Comprehensive Dataset for Camera Tampering Detection. In 2019 16th IEEE International Conference on
Advanced Video and Signal Based Surveillance(AVSS). IEEE
Preprint paper download link
The download link contains two folders.
1. UHCTD.zip (26GB): Contains the dataset
2. groundtruth_and_predictions.zip (25MB): Contains the annotaion and prediction files to reproduce results from the folder
Please fill the agreement form to download dataset.
Github: Code to train and predict using alexnet, resnet18, resnet50, densenet161 is availble on Github. CTD-Devkit, Download UHCTD.zip
Github: Code to reproduce results from the paper is available on github. CTD-Evaluation, Download groundtruth_and_predictions.zip