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This module is the original (legacy) 3D Common-Offset Multi-Focusing (CO-MF) parameter search engine. It scans each bin in the 3D survey area and searches through a table of Multi-Focusing wavefront parameters to find the best-fitting model for Common-Offset (CO) class data. The search results are written to a binary database file (.kdb), which is subsequently used by the Data Enhancement modules to reconstruct or regularize pre-stack seismic data.
This module is deprecated. For new projects, use the current Engine - 3D CO-MF Constrain module, which adds a velocity corridor constraint and additional input options. This legacy version is retained for compatibility with existing workflows.
The module supports multi-threaded CPU and GPU execution and can be distributed across a remote compute cluster. It automatically skips bins that have already been calculated in a previous run, enabling safe restart after interruption. If an existing database with conflicting parameters is found, the module will prompt whether to rewrite it.
An optional Multi-Focusing picking item that defines a velocity corridor. When connected, the search engine restricts the MF parameter search to the corridor boundaries, which improves the quality and speed of the search in areas with known velocity constraints. If left disconnected, the full parameter table is searched without restriction.
An optional 2D spatial map (matrix) of Fresnel Zone (FZ) scaling factors. When provided, this map modulates the effective aperture used to gather traces around each bin, allowing the aperture to vary spatially across the survey area. This is useful in areas with strongly varying near-surface conditions or data density. If not connected, a uniform aperture defined by the MF Tables Parametrization is applied everywhere.
The read/write handle to the SEG-Y file containing the pre-stack seismic data. This is the primary data input from which traces are read for each bin during the MF parameter search. Connect this to the SEG-Y handle of the pre-stack dataset to be processed.
A sorted trace header index for the input seismic data, organized by 3D CMP (Common Mid-Point) gather. This index allows the engine to efficiently locate all traces belonging to a given bin without reading the entire dataset. The index must be sorted in 3D CMP order; the module will report an error if a different sort order is detected.
The bin grid that describes the geometry of the input seismic dataset (inline and crossline spacing, origin, azimuth). This grid is used to correctly map trace positions to bin locations when extracting CO-class trace groups around each output bin.
The virtual Common-Offset geometry trace header collection, typically produced by the Virtual geometry CO-MF 3D module. This defines the output CO-class bin layout — where each virtual CO-class trace is located and what offset class it belongs to. The engine uses this to build the CO geometry before writing to the database. The collection must not be empty.
The Multi-Focusing table quantization item, produced by the MF Table creation module. This item defines the complete parameter search table — the discrete set of MF wavefront parameters (aperture, time, azimuth, reference angles, correlation window, minimum fold, and main frequency) that the engine will test at each bin. All MF search aperture and timing parameters are controlled by this item.
An optional spatial map of the near-surface velocity V0 (in m/s). When connected, this map provides a spatially varying near-surface replacement velocity used during MF wavefront travel-time calculations at each bin location. If not connected, the constant V0 value from the MF table parametrization is used everywhere.
Path to an optional ASCII velocity corridor file (.corr extension). This file defines the acceptable velocity range at each time-space location, restricting the MF search to physically plausible solutions. It serves the same purpose as the GMFPickingItem data connector and provides an alternative way to supply the corridor from a file on disk. If both this file and the GMFPickingItem are provided, the picking item takes precedence.
The maximum lateral distance (in meters) from a virtual CO-class bin center within which raw input traces are gathered for the MF parameter search. Default: 250 m. Increasing this value brings in more traces and improves fold at the cost of longer computation time and potential lateral smearing. Decrease this value in areas of high data density or when fine spatial resolution is required. This aperture interacts with the inline/crossline apertures defined in the MF Tables Parametrization item.
This is a parameter group containing the output database file setting.
The file path of the output 3D MF parameter database (.kdb extension). All computed CO-MF wavefront parameters for each bin are stored in this binary file. The same file is later read by the Data Enhancement module (Engine - 3D CO-MF enhancement) to reconstruct or regularize the pre-stack data. If a file with the same name but different parameters already exists, the module will prompt you whether to overwrite it. This field is mandatory.
This is a parameter group for the output bin grid configuration.
The bin grid that defines the geometry of the output MF search database — the inline/crossline spacing, origin, and orientation of the bins for which MF parameters will be computed. This grid determines which bins appear in the database and is used to triangulate the velocity corridor picking item onto the output geometry. Typically this is the same grid as, or a subset of, the input bin grid. This field is mandatory.
This group controls the spatial subsampling of bins saved for velocity analysis purposes. Setting a step coarser than 1 reduces the number of bins written to the velocity analysis database, which speeds up interactive velocity picking in subsequent QC steps.
The inline subsampling step for the velocity analysis database. Default: 5. Only every Nth inline (where N is this value) is saved to the velocity analysis sub-database. A value of 1 saves every inline. Increase this value to reduce the size of the velocity analysis database when the survey has a large number of inlines.
The crossline subsampling step for the velocity analysis database. Default: 5. Only every Nth crossline is saved to the velocity analysis sub-database. Works in conjunction with the Each inLine parameter to define a coarse 2D grid of bins for interactive velocity QC.
This group defines the spatial and temporal region over which the MF parameter search is performed. Use these parameters to limit computation to a sub-area of the full survey, for example to test parameters on a representative patch before running the full survey, or to resume a partial run over a specific zone. The current calculation area outline is displayed in the map vista below the parameters.
The first inline number to include in the calculation. Default: -1 (no limit — starts at the first inline of the output bin grid). Set this to a specific inline number to start calculation from that inline. Values less than the grid's first inline are automatically clamped to the grid boundary.
The last inline number to include in the calculation. Default: -1 (no limit — ends at the last inline of the output bin grid). Set this together with First inline number to restrict calculation to a specific inline range.
The first crossline number to include in the calculation. Default: -1 (no limit — starts at the first crossline of the output bin grid). Used together with First inline number to define the corner of a rectangular calculation sub-area.
The last crossline number to include in the calculation. Default: -1 (no limit — ends at the last crossline of the output bin grid). Used together with Last inline number to close the rectangular calculation sub-area.
Controls how bins within the calculation area are selected for processing. Two options are available:
Constant grid (default) — processes bins on a regular inline/crossline grid defined by the Step along inLine and Step along xLine parameters. The Calculation rule determines how the inline and crossline range limits are combined.
Selection by min offset — selects bins based on minimum offset proximity. This mode uses the Min offset calculation, Merge distance for min offset calculation, and Desired min distance parameters to build a spatially adaptive bin selection, which is useful for marine surveys with varying acquisition geometry.
Active only when Selection type is set to Selection by min offset. Specifies the maximum offset distance (in meters) used to define the near-offset zone for bin selection. Default: 100000 m. Bins that have at least one trace within this offset are candidates for inclusion in the adaptive selection.
Active only when Selection type is set to Selection by min offset. Specifies a merging distance (in meters) used to consolidate nearby minimum-offset positions into a single representative location. Default: 0 m (no merging). Increasing this value reduces fragmentation in the bin selection map.
Active only when Selection type is set to Selection by min offset. The target minimum spacing (in meters) between selected bins in the adaptive selection mode. Default: 1000 m. This controls the density of the adaptively selected bin grid.
Active only when Selection type is set to Constant grid. Determines how the inline range limits and crossline range limits are combined to define the rectangular calculation zone:
Logical AND (default) — a bin is calculated only if it falls within both the inline range AND the crossline range simultaneously. This produces a rectangular sub-area.
Logical OR — a bin is calculated if it falls within the inline range OR the crossline range (or both). This produces a cross-shaped selection covering the specified inline strip and crossline strip.
Active only when Selection type is set to Constant grid. The inline decimation step within the calculation area. Default: 1 (process every inline). Set to 2 to process every second inline, 3 for every third, and so on. Increasing this value reduces computation time but produces a sparser database that may require interpolation during data enhancement.
Active only when Selection type is set to Constant grid. The crossline decimation step within the calculation area. Default: 1 (process every crossline). Works in conjunction with Step along inLine number to define the output bin density.
The start of the time window (in seconds) over which the MF parameter search is performed at each bin. Default: 0 s. Set this to skip early-time samples contaminated by direct wave energy or surface noise. The value must be less than Last Time.
The end of the time window (in seconds) over which the MF parameter search is performed at each bin. Default: 6 s. Set this to the maximum two-way travel time of interest in your data. Processing beyond this time is unnecessary and wastes computation time.
This group contains advanced settings for handling edge cases in the database management workflow.
When set to true, the module will silently overwrite an existing database file even if its stored parameters do not match the current settings, without asking for confirmation. Default: false (the module will prompt you before overwriting). Enable this option only in automated batch workflows where interactive prompts are not possible. Use with caution — enabling it may cause existing computed results to be silently discarded.
Refreshes the Calculation area map vista to reflect the current values of the inline/crossline range limits, step parameters, and selection type. Run this action after changing any of the Calculation area parameters to see which bins will be included in the next execution. The map displays two overlays: all candidate bins (Calculation area) and the subset of bins with existing MF picks (Picked Bins).