It’s pretty common for security cameras to have low resolution, to use wide angle lenses, and for the significant events to be in the darkest areas far from the camera. And, in these situations, sometimes the identification of the individuals isn’t a question, but the actions of each person are key. Issues such as, who started the fight, who had the weapon, and who was where at what time, are the primary aspects in the video.

There are several ways to work on these cases, and image clarification is at the start. But, even with clarification, sometimes the action is still difficult to follow. In those cases, I have taken several approaches, depending on the situation – I’ll provide a short example to illustrate several approaches.

One approach is to create a “spotlight” that either provides enhancement to an oval around each subject, or subdues the background. The result is a spotlight, or several spotlights, that follow the subject(s) as they move through the video. This is very effective in videos that have only one or two subjects of interest, but who are difficult to discern – either because they blend in with the background, or because there is too much going on in the video.

Another approach is to make a oval or rectangle, outlined in a color, around each subject of interest. Each of these ovals or rectangles can have a different color outline to help distinguish each subject. This works well when the background information is important to see, but it is difficult to track the movements of the key subjects in the video. This can be combined with the spotlight effect.

Dots can also be used. In a case involving a fight with four individuals involved, I placed different color dots above each person’s head in a recent case. Because there were four individuals, and they often were crossing in front of each other on the video, neither the spotlight approach or the ovals worked well, but a simple, color-coded dot made it easy to follow the action in this video.

In one case I had that involved a bar fight, the lighting was bright, but the bar was crowded and the action of the one swing in the fight was difficult to see. None of the above techniques helped. Since the video was black-and-white, I decided to highlight each person with a different color. I basically painted a color over the each key person, making one red, one blue, and the third green. By applying the color with transparency, the color acted as a highlight. This made is very easy to determine the action in this case. I have used this technique in a few cases and have testified about it in court. It has proven to be very effective in making it easy to see the action in a video that is brightly lit, but has a confusing background.

Video analysis is often about determining what is happening in the video – and following the action is one of the keys to this.