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Azimuth smoothing spatially filters a seismic azimuth volume stored in a SEG-Y file, producing a noise-reduced output azimuth volume. The module is designed to work with 3D datasets where traces are organized into sections (analogous to inlines or crosslines). For each output sample, the dominant azimuth direction is estimated from a 3D neighbourhood of input samples using an eigenvector-based averaging method that correctly handles the circular (periodic) nature of azimuth angles. This prevents the wrap-around artefacts that would arise from simple arithmetic averaging of azimuth values near 0 or 180 degrees.
Use this module after computing an azimuth attribute (such as reflector dip azimuth or azimuthal anisotropy direction) to suppress short-wavelength noise and produce a geologically interpretable, smooth azimuth field. The smoothing window is fully configurable in three directions: within a section (in-line direction), across sections (cross-line direction), and vertically (time or depth). Larger smoothing windows produce smoother results at the cost of spatial resolution.
The module reads a SEG-Y file containing per-sample azimuth values. The azimuth data can be stored in either radians or degrees; set the Unit parameter to match the convention used in the input file. The input file must be a standard SEG-Y or SEGY-format file with a consistent trace layout, and the total number of traces must be exactly divisible by the Number of traces in section value.
The path to the input SEG-Y file containing the azimuth volume to be smoothed. This file must already exist and must contain azimuth values stored as seismic samples, with traces organized in a regular 3D grid layout (sections of equal size).
The path to the output SEG-Y file where the spatially smoothed azimuth volume will be written. The output file will have the same number of traces, samples, and sample interval as the input, with azimuth values expressed in the same units as the input (radians or degrees, as selected by the Unit parameter).
The angular unit used to interpret the azimuth values in the input file. Select radians (default) if the input azimuth values are in radians, or degrees if they are in degrees. This setting controls both how the input values are read and how the smoothed output values are written. Selecting the wrong unit will produce incorrect smoothing results because the circular averaging algorithm depends on correctly converting azimuth values to trigonometric form internally.
The number of traces that make up one section (for example, one inline or one crossline) in the 3D dataset. The module uses this value to divide the dataset into sections and to define the lateral smoothing directions. The total number of traces in the input file must be exactly divisible by this value; if it is not, the module will report an error. This parameter must be set to a positive non-zero integer before running. Default value: 0 (must be specified by the user).
The half-aperture of the smoothing window in the in-section direction (within each section), measured in traces. For example, a value of 11 means that each output sample is smoothed using a neighbourhood of up to 11 traces within the same section. Larger values smooth the azimuth field more strongly within each section (inline or crossline direction). The value is automatically rounded to the nearest odd integer. Default value: 11 traces. Minimum: 3.
The aperture of the smoothing window in the cross-section direction (across sections), measured in number of sections. For example, a value of 11 means that each output sample is smoothed using data from up to 11 neighbouring sections on either side. Larger values produce stronger smoothing in the cross-section (perpendicular) direction. The value is automatically rounded to the nearest odd integer. Default value: 11 sections. Minimum: 3.
The aperture of the smoothing window in the vertical direction (time or depth), measured in samples. For example, a value of 125 means that each output azimuth sample is averaged over a window of up to 125 surrounding samples vertically. This controls how much vertical smoothing is applied to the azimuth field. Increase this value to suppress rapid vertical fluctuations; decrease it to preserve finer vertical detail. The value is automatically rounded to the nearest odd integer and capped at the total number of samples in the trace. Default value: 125 samples. Minimum: 3.