- write whole SEG-Y file or part of it to disk in SEG-Y (IBM-32) format with ability to select data on base of trace index or trace header value and given time interval

- trace shift according with “Delay Recording Time” trace header value

- selection of traces to be displayed by trace index or header value

Modification History

Revision	Description
2.0	Improved user interface, new graphic display module, user's manual
2.1	Automatic gain control added
2.11	PC byte order support added
2.2	CGG Geovecteur disc SEG-Y format added
2.3	Header sequence consistency check added
2.4	SEG-Y file binary header editor added
2.5	Print to HP-Design-Jet plotter problem fixed
2.6	Save whole file or part of it to disk
2.7	Export to .bmp mode selection (color/bw)
2.8	Display of optional trace headers (bytes 181-240) added
2.9	Info about header values position (byte numbers) added
2.20	Print and Bitmap Export: - Header axis fixed (they were 1 trace shifted) - Output area extended to show last trace Removed empty pieces in wiggle display mode
2.21	Automatic detection of CGG Geovecteur disc SEG-Y (stage) format Trace shift according with “Delay Recording Time” trace header value
2.22	Time interval specification during saving file to disk Text label (one string) added to printout
2.23	Display trace headers on mouse cursor position while mouse is moving in seismic window
2.24	Selection of traces to be displayed by trace index or header value
2.25	Time lines added to seismic section

Double click program icon by mouse:

Starting the program

Double click program icon by mouse:

Main window will be shown:

Use button to toggle controls panel visibility.

Using the program

Open SEG-Y file

Select menu “File” ® “Open ”, or press button: .

Standard “Open” dialog appears. Use it for to select file that you want to browse

If your file has standard (SUN, IBM, SGI workstations) byte order, then choose “SEG‑Y (ProMAX)” in “Files of type” field.

In other case (PC byte order) choose “SEG‑Y (PC byte order).

Selection of traces to be displayed

To change the parameters choose “File” ® “Trace Selection” menu, or press button.

Fill in selection parameters form and press “Select” button, after this the program will start trace selection. When it is done, press “OK” button to display selected data or “Cancel button” to discard the selection.

Saving SEG-Y file

To save file select “File” ® “Save As ” menu item or press button.

It is possible to save all trace or part of them. Fill selection parameters in the dialog.

Then press “Save” button. When standard “File Save” dialog appears, use it to specify output file. “Close” button discards dialog.

Toggling “Apply Delay Recording Time” mode

Sometimes time of first trace sample is defined by “Delay Recording Time” trace header value. It is necessary to switch-on “Apply Recording Delay Header” to display seismic line with such traces properly. While working in this mode you can note some file opening delay, especially if file size if big. If you are sure that traces in current file are not shifted than you can toggle this mode off.

To toggle the mode select “File” ® “Apply Recording Delay Header” menu item.

Display mode selection.

“Display mode” and “Wiggle Fill” panels

The modes and corresponding controls’ positions are shown in the following table

	Mode	Controls position	Seismic sample
1	Wiggle
2	Wiggle + Positive Fill (Variable area)
3	Wiggle + Negative Fill
4	Variable density (Gray levels)
5	Color
6	Color + Wiggle

Display Mode panel controls	Description
Wiggle	Wiggle mode
Gray	Variable density mode
Color	Color mode

Wiggle Fill panel controls	Description
None	No wiggle fill
Positive	Positive fill
Negative	Negative fill

“Colors” panel

Use this panel to select colors:

Colors panel controls	Description
Wiggle	Wiggle color
Fill	Fill color
Selected	Selected trace color

Color mode palette setup

Press button to popup “Palette” dialog.

The palette consists of color markers, space between two markers is filled by linear interpolation of color.

Originally the palette is made of three markers:

#	Marker	Description
1	-100%	Maximal negative amplitude value
2	0%	Zero amplitude level
3	+100%	Maximal positive amplitude value

To select a marker pick it by mouse in the “Markers/Levels” panel.

To choose new color for a marker, use panel of colors in the right part of the dialog. Selected color will be shown “Selected Color” field. To assign the color to the selected marker, press “Assign Color” button.

To add a new marker, press “Add Marker” button. New marker will be added between selected and previous markers.

To remove selected marker, press “Delete Marker” button.

Marker position can be changed by moving marker position control by mouse.

Created palette can be saved in the system registry. Enter the palette name in text field “Saved palettes” and press “Save” button.

To load any of previously saved palettes, select it in “Saved palettes” combo-box.

To remove current palette from registry press “Delete” button.

Press “Apply” button to apply current palette to the seismic window. “OK” button also applies palette and close the dialog. “Close” remove dialog window without any effect to seismic.

Scaling and gain setup

Scale panel

Scale panel controls	Description
Traces	Set trace number per centimeter
Time	Set time scale (cm/sec)
Gain	Gain control

To adjust a value by mouse, move mouse cursor to the corresponding slider (), then press left mouse button, and (keeping it pressed) move the slider. Current value of the parameter will be shown in edit control that is on the right of the slider, and seismic image will be repainted to reflect the changes.

Direction panel

Direction panel control	Description
Normal	From left to right
Reversed	From right to left

Zoom buttons.

Button	Description
	Fit all the image to seismic window size
	Zoom by window. Press this button then draw a rectangle on the seismic window (move mouse cursor to first corner of the rectangle, press left mouse button, and keeping it pressed, move mouse to set desired size). Selected region will be zoomed to size of the seismic window.
	Return to previous zoom
	Zoom in (1.5 times)
	Zoom out (1.5 times)

Direction of scale changing caused by , , buttons depends on the following radio-buttons selection:

Button	Description
	Scale changes in both directions
	Scale changes in horizontal direction
	Scale changes in vertical direction

Automatic gain control button

After button is pressed, the program will adjust current gain, using maximal amplitude values of selected trace (see “Trace Selection article”).

Seismic window

To show this window select “Seismic” tab.

When you move mouse pointer in the seismic window, values corresponding current position will be shown in status bar at the bottom of the main window and in “Mouse Position Header Box”

Trc	Trace number in the file
Time	Time (ms)
Smp	Sample value (processing is applied!)

Axes labeling setup

Press button, to popup Axes dialog.

The dialog has two tabs. To select headers that should be shown on the top of seismic, click “Trace Axis (Headers)” tab, then check needed headers. To setup time axis labeling step click “Time Axis” tab.

Enter the step value. If time lines are needed set mark in the “Timelines” checkbox.

To accept the changes press “Apply” or “OK” button. “OK” also closes the dialog. “Close” button discards any changes and closes the dialog.

Scrolling the seismic image

There are two ways to scroll the image:

- using scroll bars

- dragging by mouse (you need to toggle “Pan” mode for this)

Press button to switch to “Pan” mode, after that you can drag seismic image by mouse. Move mouse cursor to start point, the press left mouse button and keeping it pressed, move the image into desired direction.

Trace selection

To switch into selection mode press button. It is the same button that is used to switch into “Pan” mode. Image on button, depict mode that will be selected after the button press.

While selection mode is chosen, move mouse cursor to desired trace and press left mouse button. As result, this trace becomes “selected”.

Trace header values of the selected trace will be shown in “Bin header” panel (see “Display headers” article).

This trace is also used for automatic gain control.

To select next trace press button, and button to select previous trace.

Display headers

After button is pressed, “Headers” panel will be shown in the left part of the seismic window:

Contents of the panel depends on which radio-button is checked.

Button	Contents
General	General file information
Trace header	Header of the selected trace
Bin header	Binary header of SEG-Y file
Text header	Text header of SEG-Y file

To change the panel size, move mouse cursor to the right boundary. And when the mouse cursor is changed into , press left mouse button, and holding it pressed move panel boundary into desired direction.

SEG-Y file text header editing [3]

Press “Text Header” button to show contents of the text header.

Select appropriate line of the header by mouse then enter changes from keyboard.

Modified lines are highlighted by blue color.

To save the changes press “Update” button, or press “Reset” button to undo all the changes[4].

It is also possible to load text header data from text (ASCII) file. To do this press “From file” button or select menu “File” ® “Load Text Header from File”. To load the data from the previous file, press small button that is on the right of the “From file” button.

To save the header into text (ASCII) file select “File” ® “Save Text Header to File” menu item.

SEG-Y file binary header editing [5]

Press “Bin Header” button to show contents of the text header.

Select appropriate line of the header by mouse then enter changes from keyboard. “Sample Interval”, “Number samples per data trace for reel” and “Data Sample Code” items cannot be changed because they affect to file integrity.

Modified lines are highlighted by blue color. Bad values are marked by red.

Program will not update file till all the bad values are corrected.

To save the changes press “Update” button, or press “Reset” button to undo all the changes[6].

Trace Headers window

To show this window select “Trace Headers” tab.

Check items in Selection panel that you want to display. Values of selected header items will be shown in Data panel.

The program checks for trace headers consistence. If current trace header value difference with previous trace header is not equal difference with next trace, this value is highlighted by red color.

Print window

To show this window select “Print Preview” tab.

Press “Setup” button to choose printer and page size. Standard “Print setup” dialog will be shown. Use it to setup your parameters. Information about selected printer will be shown in “Printer Info” panel.

To select orientation of plot use “Horizontal” and “Vertical” radio-buttons.

It is possible only part of seismic section, for that you need to fill in Print Region form:

Tmin	Minimal Time (ms)
Tmax	Maximal Time (ms)
From tr.	Start from this trace
То tr.	Stop at this trace

Use “min” and “max” buttons to set minimal or maximal possible values.

To place text label (one string) from “Label” edit control to printout set mark into checkbox. “File name” button puts current file name into edit control, and “Clear” button empties the control.

If image size is bigger then page size then it will be spitted into several parts.

Print preview panel shows as image is divided into pages. If you changed display mode, scaling, etc, then current changes also will be reflected in the preview panel.

To print the image, press “Print” button. The button label changes to “Abort Print”. Printing progress will be shown in progress bar at the bottom of the window..

To cancel printing, press “Abort Print” button.

While printing other work with the program is not allowed.

Export seismic into Windows Bitmap (.bmp)

Select “File” ® “Export Image to BMP file” menu item or press button, to show “Export Image to BMP” dialog.

To export part of image fill in region parameters.

Then press “Export” button. When standard “File Save” dialog appears, use it to specify output file. “Close” button discards dialog.

Export seismic into PostScript file

This can be used for saving the image in vector form for following import into CorelDraw. Only variable area mode is supported

Select “File” ® “ Export Image to PostScript”, menu item to show “Export Image to PostScript” dialog

The dialog controls are the same as they are in previous chapter.

Processing

Processing is applied to trace before it will be shown on screen. Here is the processing modules list:

- band pass filter

- automatic gain control (AGC)

- data inversion (negation)

Processing parameters setup

To set the processing parameters press button or select “Processing” ® “Parameters” menu item, after that “Processing” dialog appears. Enter parameters needed. To accept the parameters press “Apply” or “OK” button. “OK” also closes the dialog. “Close” button discards any changes and closes the dialog.

Processing panel

Use the panel to toggle corresponding processing.

Processing panel item	Description
Inversion	Data inversion (Negation)
Filter	Band pass filter
Agc	Automatic gain control

Band pass filter

Enter filter cut frequencies as it is shown in the picture and check “Use filter”, if you want to use the filter.

Original data	Filtered data

Automatic gain control (AGC)

“Window length” parameter sets AGC window length. AGC module moves the window down the trace sample-by-sample and calculates a scale factor at each location. The scale factor is equal to the RMS amplitude in the window.