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The film noise filter alters a single source, simulating some of the effects that are seen on aged film stock. This effect can be used to transform a video source into one that looks like it was shot on film that has suffered the effects of age and mishandling.

The specific features, which can be controlled independently, are:

  • Hairs: these are a simulation of hairs lying on the surface of the film. Each hair is randomly generated, and is colored in a randomly chosen shade of light grey
  • Scratches: these are vertical or near–vertical one–pixel lines drawn onto the destination image that simulate scratches in the film. Each scratch lasts for a pre–calculated length of time. During its lifespan the scratch’s position is randomly perturbed. Shortly before the scratch is removed, it will begin to shorten. The color of the scratches is a randomly chosen shade of light grey
  • Dust: these simulate dust particles on the surface of the film. Dust particles are drawn using the same algorithm that generates the hairs, but the particles are more tightly curled, and drawn in a darker shade of grey
  • Fade: this simulates an overall change in the color of the film stock. Every pixel of the source image is passed through the film fade algorithm, so this can be processor’intensive

This effect takes a single source.

The QTPlgEffectFilmNoiseDesc class implements methods and properties to setup programmatically the parameters of the film noise effect provided natively by QuickTime.







The QTPlgEffectFilmNoiseDesc class constructors are called when you create a new instance of the class, while the ˜QTPlgEffectFilmNoiseDesc class destructor, is called automatically when the class is no more in use. Also, you can invoke the class destructor by setting the instance of the class to nil.
Once a new class instance is returned, it is good practice to check the class property to be sure that the new object can be used. For discussion about the validity of an effect description instance see the documentation relative to the .

The class provides you with the following initializer methods:
()
This is the default constructor. Use this constructor to create a completely new data descriptor container in memory.
(other as )
This is the copy constructor. The properties of the object to be copied will be used to initialize the new class instance properties. Note that the parameter passed is a generic object; this is due to the fact that you could use a descriptor obtained by the that returns a generic . Anyway, the class makes a control to check if the passed object is suitable for use and, if not, will initialize the class instance with default values

controls the number of hairs that are drawn on each frame and the frequency with which hairs appear. The maximum number of hairs per frame is a randomly generated number between 1 and the value of this property. The chance of each hair appearing on a single frame is 1 in (the value of this property)
specifies the maximum length (in pixels) of the hairs being drawn
controls the number of scratches that are drawn on each frame and the frequency with which scratches appear. The maximum number of scratches per frame is a randomly generated number between 1 and the value of this property. The chance of each scratch appearing on a single frame is 1 in (the value of this property)
determines the maximum number of frames that each scratch appears for. The actual number of frames for each scratch is a randomly chosen value between 1 and this value plus 20
specifies the maximum width, in pixels, of a scratch. The actual width is a randomly chosen number between 1 and this value
controls the number of dust particles that are drawn on each frame and the frequency with which dust particles appear. The maximum number of dust particles per frame is a randomly generated number between 1 and the value of this property. The chance of each dust particle appearing on a single frame is 1 in (the value of this property)
for each dust particle, the length in pixels is a random number between 1 and 5, plus the value of this property
specifies the type of film fade effect (if any) to apply. You can use only the defined below


the destination image is a copy of the source
the destination is a slightly saturated, monochromatic version of the source, colorized into shades of light red–brown
the destination is a greyscale version of the source
the destination is a color desaturated version of the source
the destination is a color supersaturated version of the source