## 4 Experimental Results and Analyses
### Experiment on Image-Query-Based Video Searching
#### 4.3.3 Experiment on Our Video Searching and Fingerprint Detection Dataset  
The source video dataset for video searching and fingerprint detection was composed of 110 videos, including 4 videos in the OSVD datasets; the other videos are mostly music clips. Information on the video data is shown in Figure 15.  
Video distortions can be made by using signal processing, geometric transformations, and desynchronization. To search for and detect a fingerprint of the video in a higher accuracy by using the features of a single image or shot sequence, the proposed method must stand against most of those various distortions. Due to our method being based on a query image, the common attacks for an image are considered. Attacks on audio and video desynchronization are not included. Common transformations are listed in Table 18.  
To test the performance of our image-to-video method, a combination of transformations is used. The processing orders and samples of the attacked images of each attack type are also shown in Table 19. The processing parameters of each attack are the same as shown in Table 19.  
For the query images, we took 200 random frames for each video from the OSVD dataset. For other videos, because their durations are less than 3 min, we take 20 random frames from each of those videos; otherwise, we take 250 poster images from the website as false examples. So, there are a total of 3170 original query images. Then, we apply the transforms listed in Table 18 to make the source video search task difficult. Finally, 34,870 query images are generated. We used two thresholds in the feature matching and decision stage. The first threshold is the UBCMATCH threshold; the other one is the matched numbers threshold for fingerprint detecting decisions. The parameters in the experiment are listed in Table 20. \begin{table}
\begin{tabular}{c c c} \hline \hline
**ID\_VT** & **Video Transformations** & **Parameters** \\ \hline VT1 & Flip & Horizontal flip \\ VT2 & Contrast change & 10\% \\ VT3 & Noise Addition & Gaussian: mean = 0; variance = 0.01 \\ VT4 & Brightness change & 10\% \\ VT5 & Cropping & 10\% of the frame border \\ VT6 & Rotation & +5\({}^{\circ}\) \\ VT7 & Geometric projection & \(\theta\) = 1\({}^{\circ}\), projective 2d = ([cos(\(\theta\)), \(-\)sin(\(\theta\)), 0.001; sin(\(\theta\)), cos(\(\theta\)), 0.001; 0, 0, 1]); \\ VT8 & Picture in picture & Original video resized to 90\% at the front, background image randomly used \\ VT9 & Picture fusion & original video and background images are added, background alpha value = 0.4 \\ VT10 & patterns insertion & Patterns are random images and occupy 2.25\% of the area of the Original video \\ \hline \hline \end{tabular}
\end{table} 
Table 18: Examples of common video transformations. Figure 15: Information on the size, frame rate, duration, and detected shots in our test dataset. Here, the experiments are conducted under the parameters listed in Table 20. Additionally, image queries from the source videos without transformations are taken for the experiments. The goal is to study the effects of those factors on image-query-based video searching. To simplify the comparison experiments, a control group with the parameters of a 128-pixel image size and application of the step skip frames method and the SIFT descriptor is used to compare the experimental results for different factors. The results of the video searching and shot searching are shown in Figure 16. Shot searching detects a shot's location in a particular video, so the accuracies of it are lower than video searching. Compared to video searching, the shot searching accuracies have decreased by at least 0.1. One reason is that a video may include many similar shots, especially for interview videos. When the UBCMATCH threshold is lower than 1.6, there will be more false alarms; as a result, the searching results are much lower. When the UBCMATCH threshold is higher than 3, there will be lower recall; therefore, the searching results show a declined tendency.