Noise

The image sequence to which noise is added.

The noise is rendered into these output channels.

If you set this to something other than none, you can use the checkboxes on the right to select individual channels.

Premultiply multiplies the chosen input channels with a mask representing the noise. For example, where there is no noise (the matte is black or empty), the input channels are set to black. Where the noise is opaque (the matte is white or full), the input channels keep their full value.

NOTE:  Selecting rgba premultiplies the alpha against itself (a*a). If you don’t want this to happen, set premult to rgb instead.

Select how to restrict the output image:

• no clip - use the entire image.

• bbox - restrict the output image to the incoming bounding box.

• format - restrict the output image to the incoming format area.

• unionbboxandformat - restrict the output image to a combination of the incoming bounding box and format area.

• intersectbboxandformat - restrict the output image to an intersection of the bounding box and incoming format area.

When enabled, existing channels are cleared to black before drawing into them. You might find replace useful, for instance, if you’re creating a mask in the alpha channel, but the incoming image already has an alpha channel which you want to throw away.

When enabled, inverts the new noise and non-noise areas.

Sets the noise opacity where 0 is equal to transparent, and 1 is equal to opaque.

Enables the associated mask channel to the right. Disabling this checkbox is the same as setting the channel to none.

The channel to use as a mask. By default, the noise is limited to the non-black areas of this channel.

Copies the mask input to the predefined mask.a channel. Injecting the mask allows you to use the same mask further downstream.

Inverts the use of the mask channel so that the noise is limited to the non-white areas of the mask.

Choose the type of noise to use:

• fBm (fractional Brownian motion) - runs noise() octave times at different scales to get random numbers between -1 and +1 and adds them up.

• turbulence - similar to fBm except it uses the absolute value of the noise function so the values it sums up are all between 0 and 1.

Sets the lowest possible noise frequency on the x and y axes. For example, low y values relative to x produces horizontal noise.

Offsets the noise to create new patterns. This control must be animated to produce noise changes over time. For example, the expression frame/10 causes the noise to change completely over 10 frames.

Sets the number of Perlin noise functions to add to the noise frequency.

When enabled, limits the number of octaves so that the highest frequency is larger than one pixel.

NOTE:  You may need to disable this control if you’re animating the size of the noise, as changes can be visible.

Sets the amount by which octaves multiply noise frequency. Lower values produce smoother noise and higher values produce more granular noise.

Sets the amount by which octaves multiply noise amplitude.

Sets the gamma output for the noise.

Translates the noise along the x and y axes. You can also adjust translate values by dragging the transform handle in the Viewer.

Rotates the noise around the center x y coordinates. You can adjust rotate values by dragging the transform handle in the Viewer.

Scales the noise width and height around the center x y coordinates.

Skews the noise on the x and y axes.

Sets the center of rotation and scale on the x and y axes.

Rotation around the x axis in 3D noise space. Setting this to zero reveals artifacts in the Perlin noise generator.

Rotation around the y axis in 3D noise space. Setting this to zero reveals artifacts in the Perlin noise generator.

Selects whether to create a color gradient across the noise:

• none - don’t create a color gradient.

• linear - the ramp changes linearly from one color into another.

• smooth0 - the ramp color gradually eases into the point 0 end. This means colors in the point 0 end are spread wider than colors in the point 1 end.

• smooth1 - the ramp color eases into the point 1 end. This means colors in the point 1 end are spread wider than colors in the point 0 end.

• smooth - the ramp color gradually eases into both ends. This means colors in the point 0 and point 1 ends are spread wider than colors in the center of the ramp.

Sets a color for the noise.

If ramp is set to anything other than none, this is the color for the ramp at the point 1 end (by default, the top end).

Sets the position of point 1. This allows you to adjust the spread and angle of the ramp.

This control is only available if ramp is set to anything other than none.

Sets the color for the ramp at the point 0 end (by default, the bottom end).

This control is only available if ramp is set to anything other than none.