An actor with flames in his eyes may seem like a complicated effect to achieve, but we want to show you that thanks to Kdenlive you can get excellent results without having to resort to complicated, expensive, and not free software like After Effects.
In a film with visual effects you can do anything, but sometimes the best result is obtained with small changes, which keep the scene realistic enough not to appear grotesque. For example, how can a very angry person present themselves? We could transform the actor to make him look monstrous, which often happens in cartoons. But perhaps something simpler can still make us have a good effect: what is the most famous example of an angry character? Certainly the Charon of the Divine Comedy. He is described as a man with fiery eyes and a low voice. If we want to insert an angry person into our movie, then, we can refer to this character. Making a low voice is pretty easy, thanks to Audacity. There are two ways to change the pitch of the voice: the most classic is to change the speed. It works quite well, but obviously the audio can no longer coincide with the video (because they have different speeds and therefore different length). The effect Change intonation of Audacity, however, can do a little magic: keep the speed intact and only change the tone. This is what it does for us, because the resulting audio will be perfectly superimposable on the original movie. And the flames in the eyes? This is why Kdenlive comes to our aid, with the trusty effect rotoscope . And of course, we will need the movie of a flame. The trick is quite simple: just superimpose the film of the flame on that of the actor. Then the original footage is superimposed on the flame and the eyeballs are cut out of it. In summary, we have three levels, from the highest to the lowest: the face, the flames, the eyes. An important part for the success of the effect is that the flame has a slightly larger size than the eyes. In this way the result is that the fire really seems to be positioned between the iris and the outermost part of the face. If, then, the flames are slightly transparent and allow the pupil to glimpse the effect is much more likely. Obviously, in these cases the concept of verisimilitude is rather singular: it is obvious that the image cannot be realistic, no person could really have flames inside their eyes and remain alive. What matters is the impression that the viewer has in the first moment: when we watch a Pixar cartoon we know that the characters cannot be true, yet they appear plausible (even if we see a green and cyclopean anthropomorphic monster) because overall are credible. Even while realizing our effect, therefore, it is essential to keep in mind that we want to build something that can convince viewers even if it is not realistic, otherwise it will appear grotesque. One of the things that contributes to making the effect plausible is the feathering of the rotoscope: it can easily be seen that in its absence the contour of the eyes is too sharp and the flames are detached from the face. The feather, on the other hand, dampens the margins of each flame and places it in the context in a much more credible way. You can find the example video at the following address: https://www.youtube.com/watch?v=bbxqonG-Kbs
DetFilmsHD
For this effect, shooting of flames is needed. Our sample movie is based on the clips made by detfilmshd ( http://detfilmshd.com/G_Collections_PKFireColumns.html ) which have the advantage of being supplied with a transparent background, and can therefore be used in Kdenlive without the need to apply a chromatic key. Of course, good fire can also be achieved with a chroma key on a blue background. Just film a flame (made with a balled cloth and soaked in kerosene, like old torches) in front of a blue background. We suggest you use blue because green would be confused with flame yellow and black never allows an optimal chroma key.
What a strange voice you have…
Let’s start working on the audio of our movie
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“Dubbing” with the modified voice
Let’s change the tone of the voice and replace it with the original one
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All in position
The clips must be moved to coincide with the eyes
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A “controlled” fire
The flames must not come out of the area around the eyes
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