Match Grain effect



The Match Grain effect matches the noise between two images. This effect is especially useful for compositing and in bluescreen/greenscreen work. The Match Grain effect only adds noise and can’t remove it, so if the destination is already noisier than the source, an exact match is not possible. In this case, you can first use the Remove Grain effect to clean up the destination and then apply the Match Grain effect to the result to get a perfect match.

The Match Grain effect uses noise sampling as its starting point. Basically, entire frames of new noise are synthesized to match the noise samples. You can modify the noise in many ways before the effect is applied to the new image, such as duplicating the noise from an image but making the noise larger and redder before applying the noise to another image.

The Match Grain effect shares some controls with the Add Grain effect. (See Add Grain effect.)

Note: The Match Grain effect samples the noise on the frame in the source layer that corresponds to the first frame in the destination layer. If the source layer is not present at that frame, or if the noise samples contain transparent areas, no noise is sampled or applied.

This effect works with 8-bpc and 16-bpc color.

Original images (left), and with effect applied (right)

Match noise or grain between images

  1. Make sure that the source and the destination layers are in the same composition.
  2. Select the destination layer to which you want to add grain.
  3. Choose Effect > Noise & Grain > Match Grain.
  4. Choose a layer from the Noise Source Layer control in the Effect Controls panel to specify the source layer from which you want to sample the grain. (The Noise Source Layer control lists only layers that are in the Timeline panel.)

    The grain is automatically sampled and applied to the preview region on the destination layer. If you need an automatic match, you can skip the remaining steps.

  5. If there already is significant noise in the destination layer before choosing a noise source layer and this causes a grain mismatch, adjust the Compensate For Existing Noise slider to avoid grain build-up.
  6. Do any of the following:

    • To adjust the intensity and size of the applied grain and to introduce a blur, adjust the Tweaking controls.

    • To modify the color of the added noise, adjust the Color controls.

    • To determine how the color value of the generated noise combines with the color value of the underlying destination layer at each pixel, choose a Blending Mode in the Application controls group.

    • To define how much grain is added to each tonal area in your image and the midpoint, adjust the Shadows, Midtones, Highlights, and Midpoint values in the Application controls group.

  7. If you want to change the effect view, choose any of the following from the Viewing Mode menu in the Effect Controls panel:
    Noise Samples
    Shows the areas that have been sampled to extract the current noise model. Selecting the source layer causes it to appear in the Composition panel, with its noise sample squares displayed.

    Compensation Samples
    Shows the noise samples that have been automatically extracted from the destination image.

    Preview
    Displays the current settings of the applied effect in a 200x200 pixel area.

    Blending Matte
    Shows the current color matte or mask, or the combination of both, which results from the current settings of the Blend With Original controls group.

    Final Output
    Renders the full active frame, using the current settings of the effect.

  8. Animate the added grain, if desired.
  9. Choose Final Output from the Viewing Mode control.

Compensate for existing noise when matching noise

If you’re trying to match the grain between images with the Match Grain effect, and your destination layer already has its own visible grain, a grain mismatch or grain build-up may occur. To prevent these problems, the Compensate For Existing Noise control extracts a noise model from both the source and the destination and then modifies the noise from the source to account for the noise already present in the destination, before applying it to the destination.

To use this control automatically, set the Compensate For Existing Noise slider to 100%. You can then view the noise samples in the destination layer by choosing Compensation Samples in the Viewing Mode menu. You can also reposition the samples in the destination image by setting Sampling Mode to Manual, which makes the Compensation Sample Points available for manual repositioning.

  1. Apply the Match Grain effect to the destination layer.
  2. In the Effect Controls panel, adjust the Compensate For Existing Noise value under the Match Grain effect as needed. The noise in the source layer and the noise in the destination layer are sampled, and their difference is calculated, so that only enough noise to match the destination layer to the source layer is applied to the destination.
  3. To modify the noise samples, choose Noise Samples from the Viewing Mode menu, change the Sampling > Sample Selection control to Manual, and then expand the Compensation Sample Points. The current value of Number Of Samples determines how many points are available.
  4. To reposition each sample point, do any of the following:

    • Drag each sample point in the Composition panel to a new location.

    • Enter new x and y coordinates adjacent to the sample point under the Compensation Sample Points controls in the Effect Controls panel.

    • Click the point parameter  for the Compensation Sample Point in the Effect Controls panel, and then click where you want to move the point in the Composition panel.

  5. Choose Final Output from the Viewing Mode control.