PremierePro

Adjust edges, blurs and brightness using Convolution presets

You can control the fine details of blurring, embossing, sharpening, and other effects by applying the Convolution Kernel effect or one of the convolution presets based on it. Convolution Kernel, and the presets based on it, apply a grid of brightness values to each pixel in a frame and all its neighbors, one pixel at a time. You can set the values for each cell in the grid using sliders in the Effect Controls panel, and you can use keyframes to change these values over time. To achieve a desired effect, it is often easier to apply one of the convolution presets and to modify it, than to apply and modify the Convolution Kernel effect itself.

  1. In the Effects panel, click the triangle to expand the Video Effects bin, and then click the triangle to expand the Adjust bin.
  2. Drag the Convolution Kernel effect to the clip in the Timeline panel.
    If the clip is already selected in the Timeline panel, you can drag the Convolution Kernel to the Video Effects section of the Effect Controls panel.
  3. In the Effect Controls panel, click the triangle next to Convolution Kernel to expand it.

    Each of the settings that start with the letter “M” represents a cell in a 3X3 matrix. For example “M11” represents the cell at row 1, column 1. “M22” represents the cell in the center of the matrix.

  4. Click on a number next to any of the cell settings.
  5. Type a value (from –999 to +999) by which you want to multiply that pixel’s brightness value.
  6. Repeat the last step for all pixels that you want to include in the operation. You don’t need to type values for all of the cell settings.
  7. Click the number next to Scale, and type the value by which to divide the sum of the brightness values of the pixels included in the calculation.
  8. Click the number next to Offset, and type the value to be added to the result of the scale calculation.
  9. Click OK.

    The effect is applied to each pixel in the clip, one at a time.