We use Kdenlive to design a time bomb display with a countdown timer: not only it is simpler to build a fake bomb but, since the numbers are added in post production, we can easily synchronize them to the actors’ acting.
Can you make an action movie without a bomb to defuse? Yes, of course, but it would be boring. Of course, making a fake explosive device with the classic timer is more complicated than you might imagine. Not so much for the bomb itself: you can easily fake one by gluing a couple of cardboard rolls, plasticine, or a pack of lithium batteries together. The difficult part is to make the timer, both because they are not easily found, and because during the shooting we will need to coordinate the countdown (the countdown, in English) with the actions of the actors, and it may not be very easy, especially if we have to shoot from multiple angles and if an act must perfectly coincide (for example, the countdown must stop exactly when the actor cuts a certain electric cable). The solution, as always, comes from Kdenlive, and consists in creating the timer in postproduction. The idea is therefore very simple: we will make a fake bomb with a display, the classic screen on which the numbers for the countdown will appear. The screen, however, will remain off during shooting. We will bring up the numbers thanks to Kdenlive. All we need is a movie containing numbers running in a countdown, drawn with a nice bright color on a black background. We can then superimpose this movie on the original shot using a transition of type screen . The screen transition, in fact, simulates a screen, so it is perfect for our purpose. To have control over the position of the numbers, which obviously must be adapted to the position of the display in the filmed footage, we will use two transitions. In fact, we will not apply the countdown directly above the original video: we will superimpose the countdown to a completely black clip, using the transition of type Affine , or Composite , which allows us to correctly position the numbers in the frame. Then, we will superimpose this completely black clip over the original shot using the screen transition. Among other things, we can choose between screen is addition : the second transition has a brighter result. Of course, the fact that the intermediate clip is completely black is not a problem, because this type of transitions makes the black color completely transparent. The advantage of these transitions, instead of directly using the Affine , lies in the fact that these two transitions transfer the color as if it were a light, while maintaining a part of the color and shape of the original shot, with an obviously more realistic result. In fact, this means that if in the original shot we have a display with dust, the result will still reveal the dust. The point, therefore, is: how to easily make a countdown with a black background? Of course we can make every single frame with a drawing program like GIMP. This offers us the important advantage of having everything under control and making the numbers exactly as we want. However, if we want something simpler, we can take advantage of a special Kdenlive generator, which produces countdown movies automatically: all we have to do is indicate the settings we want, such as the fact that the countdown reaches 0 and that the account in reverse is represented by a single number or by the classic format hours: minutes: seconds: tenths. Kdenlive will do the rest for us, and we will only have to make some changes to the video produced to obtain the color we want. As always, you can see the example video at the following address: https://www.youtube.com/watch?v=zwxk2cLM-Cg
The orange-blue lighting
The majority of action films, today, tend to present a very specific color: a mixture of orange and blue. It is not a coincidence, nor a technical problem. The fact is that it has been noticed that these two colors are highly emotional for the public: blue conveys a feeling of frost, fear, and sadness. Orange conveys warmth, tranquility and happiness. In action films these two colors are often used together, applying colored jellies in front of the lamps: for example, orange is used to illuminate the characters’ faces, and blue for the background. This allows to induce a certain tension in the spectator, typically due to the predominance of blue (since the background often occupies most of the frame). But there is also an emotional bond with the protagonist, who being illuminated in orange immediately appears as a positive character, and as a point of reference for escaping from the coldness of the rest of the scene. Color photography is used precisely to build the emotions that the viewer will have to feel while watching the film.
An automatic counter
Kdenlive automatically produces our countdown timer
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Change the color
The Kdenlive counter is gray: for our diplay we have to color it
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Superimpose the countdown on the display
Using the various video tracks of Kdenlive, we can overlay the clips
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The right transitions
To achieve the “screen” effect, we need a special transition
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