1. In the Control Panel, open the Process tab.
2. Click the Add icon and select New Process.
3. Double-click Gain.
4. Type a name for the process and click OK.
5. In the Details Panel, at Volume, select the volume to apply the gains.

1. In the Gain settings section, select Data dependent (AGC).
2. Select a Gain function to apply:
   • Arithmetic mean within a window
     — The average of the window values (see Arithmetic Mean).
   • Median within a window
     — The median of the window values (see Median).
   • Geometric mean within a window
     — The geometric mean (nth Root of (a * b * c * d... n)) (see Geometric Mean).
   • RMS within a window
     — The Root Mean Square / quadratic mean (see Root Mean Square).
   • Median mean within a window divided by the arithmetic mean
     — Arithmetic mean of the middle N values in the window, where N is the window trimmed by the specified Percentage trim. Median mean, otherwise known as alpha-trimmed mean, is computed by ranking the values within a window from smallest to largest, removing the smallest and largest %, and averaging the remaining values. For example, a 40% trim would remove the smallest 20% and largest 20% of values, then average the remaining 60%. This is more robust (though more computationally expensive) than straight mean, as it is unaffected by outliers.
3. The Gain process also comes with a clipping functionality to clip scalars.
4. Select the Output additional scalars volume check box to produce a volume of scalars as the output, instead of the gained data itself. These can be applied to the data using Volume Maths (data * scalars), and later reversed (seismic/scalars) (see below).
5. Enter the Window length and Window overlap. For each trace, a single scalar is calculated for each window, blended together in the area of overlap.
6. As a result of this process, a new volume (with the same name as that given to the process) is available in the Volume tab.

Tip: To quickly open the output volume, right-click the process and select Open Child Volume. Likewise, you can open the process from the Volume tab by right-clicking the volume and selecting Open Parent Process.

1. In the Gain settings section, select Data independent.
2. Select a Gain function to apply (see below for details of each function):
   • Power of t
   • velocity * velocity * time
   • Exponential
   • dB per second (or unit depth)
   • Time/Depth - Gain pairs
3. Select Direction to Apply or Remove the gain. In all cases, the gain is normalised such that it is 1 at the first data point to which the gain is applied (this may not be the top of the trace due to windowing). The gain functions can be started and stopped at a specified horizon or constant time. In such cases, the gain at the bottom of the selected data range is applied to the remainder of the trace.
4. Select Windowed or Entire Volume to apply the process within a defined window or on the entire volume.
5. If Windowed is chosen, select Constant or Horizon to define the windows. If horizons are chosen, you can optionally input a constant to offset the horizon.

As a result of this process, a new volume "Gain" is available in the Volume tab.

Important notes:

• If you are using a depth-domain input volume, you must have defined a velocity volume (see Converting Time-Depth) in order to use the Power of t, velocity * velocity * time, or Exponential gain functions.
• For windowed data (where top and bottom horizons are specified), the gain applied is always 1 above the top horizon, and the gain at the bottom horizon is applied to all deeper samples.

Tip: To quickly open the output volume, right-click the process item in the Process tab and click Open Child Volume. Vice versa, you can also open the process from the Volume tab directly. To do this, right-click the volume which was created from a process (indicated in italics) and click Open Parent Process.