Kdenlive allows us to superimpose videos depicting fire on the videos of our camera, positioning them in order to compose the writings. With a few tricks and the right transition, a few steps will be enough to draw texts with fire.
Fire is something that has always fascinated men, and it is no coincidence that the flames are continually inserted into the films: often in the form of candles or torches to illuminate the scene making it more adventurous. Or, a sudden fire to get a dramatic scene. But also something more bizarre: writing with fire. Fire writing is a method used especially in Asian cultures, often in conjunction with fireworks displays, during public events. But in western culture the idea of writing words with flames is often associated with the devil, or with other supernatural causes. Typically, when shooting a film with mediums who contact a ghost, the latter interacts by writing meaningful words on wooden boards, and one of the methods that can be used is writing with fire. Or, a person apparently endowed with supernatural powers can magically bring up fiery writing on a floor. Obviously, an effect of this type can be achieved in the room, without the need for computer graphics: just get a flammable liquid, preferably not too volatile, and use it as ink to write a word. Then just set the liquid on fire with a match, and turn on the video camera. However, this is a bad idea. Because fire is dangerous, however many precautions you can take, it can always get out of our control, and it’s easy for someone to get hurt. Without considering that we may want to make fire appear on objects that we don’t really want to destroy. If we really wrote with fire on the table in our dining room, then we will have lunch with the plate on our knees. Computer graphics, therefore, can be the safest, least expensive, and ultimately most reliable solution, because in the real world it can be difficult to get the image we want, the flames are unpredictable, while with Kdenlive we can give the fire any shape we want. First of all we will need the image of a flame: on the internet there are a couple of sites that offer ready-made videos of burning flames, in some cases even free of charge but generally at a cost of around ten euros. Obviously, the movie takes only one flame, but if we want to write words we will need a line of flames: with a line of fire, we can obviously use it as if it were a “stick” with which to write texts. Have you ever tried to write words with toothpicks? Here, the mechanism is identical. We will therefore use Kdenlive to glue together several flames to form a row: there are several ways to do it, we propose to support them because it is the shape that lends itself to most situations. Once a row of flames is obtained, we will export the video with the fire on a black background. Then, taking advantage of the Screen composition method, which makes black and bright everything else transparent (like on a computer screen), we can insert the line of flames superimposed on the video we made with the video camera. As always, you can see the example video at the following address: https://www.youtube.com/watch?v=ddlSl7BKFpw
Filming a flame
If you don’t want to buy a movie of a flame on the internet, you can make one yourself, obviously paying close attention: fire is dangerous, and you shouldn’t play it unless you know exactly what you are doing. The trick to picking up a flame is actually quite simple: you need to get a black background, preferably made with a non-flammable material such as opaque plastic. The color must be really black, not gray or dark blue. Then just place the video camera in front of this background and between it and the background itself place the flame (for example a candle, or a sheet of burning paper). The camera must be set with very low exposure times, otherwise the image will be blurred, and a very closed aperture. The advantage of a closed diaphragm is that the contrast of the image will be very high, so the flame will be very bright and the background totally black. With Kdenlive you can then make the background disappear with the transition Composite and Transform using the overlay mode Screen .
A flame on a black background
We superimpose the film of a flame on a black background
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A whole line of flames
We add more tracks so that we can combine more flames
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Flames enter the real world
We insert the movie with the fire superimposed on the clip shot with the video camera
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Draw the text with flames
Let’s add a line of flames for each segment of the text
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