SEG‑D Monitor Download

Airgun source QC for marine seismic crews

Catch source problems while the line is still being shot.

SEG‑D Monitor reads every shot the moment its file lands and checks each gun and each near-field hydrophone against its limits. When the line ends, the report is already written.

Download free See it at work
  • The core monitor is free, and stays free
  • Every feature free for three months
  • No account, no card
  • Windows · macOS · Linux

Scroll, and go under. The source fires every 30 seconds.

Every gun, on every shot.

This is what hangs five metres under each float: guns, singly and in clusters, each with a hydrophone a metre above it. The app reads what every one of them did on every shot.

Firing time
against the aim point
Depth
against its limits
Pressure
against its limits

The limits are the ones written in the SEG‑D header. A gun that drifts shows before it breaks one.

An air leak, told from a bad hydrophone.

Both look the same at first: one hydrophone stops reading like the reference. Try each: the view goes in close, and the sea and the map show it together.

Similarity to the referenceSP 1041

A simulation in your browser, on invented numbers; each choice fires six shots to show it. The app's own screens are further down.

The report is ready when the line ends.

An End of Line PDF with every finding on its cover, a heat map for every gun and the contract spec check - made in one click, or by itself when the line stops.

SEG-D Monitor while a line is being shot: similarity heat maps for three sources, an alarm naming a hydrophone that dropped together with its neighbours, the session and QC panels, and the log. The cover of the End of Line report it writes, standing in front of the window.
The app on a line being shot, and the report it writes · synthetic demo data

Windows

Windows 10 / 11 · 64-bit · v2.28.0 · 299.8 MB

Download

SHA-256 fb4482659c175043466612865fecaf75c884a806794deadbcfcbfb4a0494f1da

Needs Windows 10 or 11, 64-bit. Unpack the ZIP first (Extract All), then start SEGDMonitor.exe from the unpacked folder.

macOS

Apple silicon (M1 or later) · v2.28.0 · 347.3 MB

Download

SHA-256 8ae059add27af539361822dccef920da9482e83b4a1e4e8eec924543511386b1

Needs macOS 15 or later. It may run on macOS 13 and 14 too; that has not been tried.

Linux

x86_64 · v2.28.0 · 279.5 MB

Download

SHA-256 6989db013d004913d80a737e4d1f4a5b8b6d98d1024156759522d5ac51f5df38

Needs glibc 2.35 or newer: Ubuntu 22.04, Debian 12, or later. Checked on Ubuntu 22.04, Ubuntu 24.04 and Debian 12. Unpack, then run x_corr_app_v1_5_0.dist/segd-monitor.

Current version: v2.28.0 · check the SHA-256 checksum after downloading · older versions on request · it will not start?

Why use it

A source fault found after the line can mean shooting it again.

SEG‑D Monitor finds it while there is still time to act - and does the paperwork that follows.

Every gun, every shot

Firing time, depth and pressure of each gun are checked against the limits written in the SEG‑D header as the shot lands. A gun that drifts shows before it breaks its limit.

An air leak, told from a bad hydrophone

When one hydrophone drops, the app looks at its neighbours. If they changed with it, the area is outlined and an alarm sounds until someone answers it.

The report is ready when the line ends

An End of Line PDF with every finding on its cover, a heat map for every gun and the contract spec check - made in one click when the line ends.

It can change lines by itself

Automatic mode stops a line when its files stop arriving, makes its report, and starts the next line folder - reading the direction from the shot points.

Bubble tests without the spreadsheet

The bubble period of every gun, measured against the computed one, passed or failed, with a PDF report and the history of every test in the project.

Nothing leaves the vessel

The app never connects to the internet. No cloud, no account: the licence is a file, and your data stays on your machine.

See it at work

The screens a crew works with, and the reports it hands over.

Every picture is from the app itself, on synthetic demo data. Pick one.

  1. Cross-correlation screenEvery hydrophone of every shot against the reference, per source. When a hydrophone and its neighbours change together the area is outlined and an alarm calls: an air leak, not one bad sensor.
  2. Live gun QCDepth, timing and pressure of every gun as a heat map: a row a gun, a column a shot point, red only where a reading is outside the limits written in the SEG‑D header.
  3. Source Array DesignerDraw arrays, sub-arrays and clusters; the navigation masks are worked out from the drawing.
  4. SP QualityThe contract spec check per source: where the line went out of spec, and which shot-point ranges are acceptable.
  5. End of Line reportThe cover says the line in plain words and lists every finding; timing, depth and pressure follow as gun heat maps, red only where a limit broke.
  6. Volume and hydrophone recordsHow many shots were at full volume, and which guns did not fire on the short ones; then what each hydrophone recorded on every shot, with its median pulse and a verdict.
  7. Far-field signatureEach cluster's energy and bubble period along the line as heat maps, and the median far-field signature with its amplitude spectrum.
  8. Hydrophone QCEvery hydrophone of the active guns against its own line median, beside the gun depth map.
  9. Bubble Test reportA pass or fail for every gun on the cover, and a page for each gun: what it fired with, its hydrophone's signal on every shot with the primary and bubble picked, and where it sits in the source.
  • The main window while monitoring a line: similarity heat maps of three sources, one area outlined in black with an alarm bar above it naming the hydrophone and its neighbours, and the session, QC and log panels beside them.
    Cross-correlation screen Every hydrophone of every shot against the reference, per source. When a hydrophone and its neighbours change together the area is outlined and an alarm calls: an air leak, not one bad sensor.
  • The live gun QC panel in its heat-map view: the 24 guns of a source down, shot points across, one gun's row deepening from blue-grey into red as it drifts past its depth limit, and two short red spells on other guns.
    Live gun QC Depth, timing and pressure of every gun as a heat map: a row a gun, a column a shot point, red only where a reading is outside the limits written in the SEG‑D header.
  • The Source Array Designer: four sub-arrays of clustered guns drawn on a canvas, with the array and navigation-mask settings beside them.
    Source Array Designer Draw arrays, sub-arrays and clusters; the navigation masks are worked out from the drawing.
  • The SP Quality window: one track per source along the shot points, red spans where the spec was broken and green spans where it held.
    SP Quality The contract spec check per source: where the line went out of spec, and which shot-point ranges are acceptable.
  • Two pages of an End of Line report: the cover with its verdict, a block of plain sentences about the line and the list of findings, and timing heat maps where one gun drifts into red.
    End of Line report The cover says the line in plain words and lists every finding; timing, depth and pressure follow as gun heat maps, red only where a limit broke.
  • Two End of Line report pages: delivered volume as a band with the short shots listed beside the guns that did not fire, and a table with one row per hydrophone - its record on every shot in colour, its median pulse, its figures and a verdict.
    Volume and hydrophone records How many shots were at full volume, and which guns did not fire on the short ones; then what each hydrophone recorded on every shot, with its median pulse and a verdict.
  • Two far-field report pages: heat maps of twelve clusters along the line, one cluster fading and a run of weak shots in blue, and the median signature of three sources with its amplitude spectrum.
    Far-field signature Each cluster's energy and bubble period along the line as heat maps, and the median far-field signature with its amplitude spectrum.
  • Two report pages: hydrophone heat maps in blue and amber against each hydrophone's median, and a gun depth heat map with one excursion in red.
    Hydrophone QC Every hydrophone of the active guns against its own line median, beside the gun depth map.
  • Two pages of a Bubble Test report: the summary with one failed gun of eight, and that gun's page - measured and computed bubble period, depth, pressure and volume, its signal on five shots, and its position in the source marked in red.
    Bubble Test report A pass or fail for every gun on the cover, and a page for each gun: what it fired with, its hydrophone's signal on every shot with the primary and bubble picked, and where it sits in the source.

Every feature, free for three months

Every feature, on one machine. Renew it every three months for up to a year; after that, contact us for a full licence.

  1. Install SEG‑D Monitor v2.26.3 or later, and open it.
  2. Copy your machine ID from 🔑 License - or click Get a free licence online there.
  3. Get your licence here, then 🔑 License → Load License File…

Three months at a time, up to 12 months per machine. Your details are kept only to know who uses the software; no emails are sent.

Before you download

Is it really free?

The core monitor - watching the folder, decoding every shot, the similarity heat map, the live graphs, the project database - is free and does not expire, for one source. A free licence from this page adds everything else, on every source, three months at a time for up to a year per machine. After that, write to us for a full licence.

What does it read?

GunLink SEG‑D files (format 1.0) with near-field hydrophone traces, as the recording system writes them into a folder - on a local disk or on a network share. Point it at the folder; it takes each new file as it arrives.

Does it need the internet, or send anything anywhere?

No. The app never connects to the internet, and nothing it reads or writes leaves the machine. The only time a browser is involved is when you fetch a licence file from this page - which can be done from any other computer.

Can it disturb the acquisition?

It only reads. It waits until a file has stopped growing, opens it for reading, and writes its own database and reports into a separate project folder that you choose.

Troubleshooting

If it will not start

The messages you may meet, why they appear, and what to do.

Windows

You see

“Windows protected your PC”

Why

SmartScreen shows this for a newly downloaded program that carries no publisher's signature. It is about the download's reputation, not about the program.

Do this
  1. Click More info
  2. Click Run anyway
You see

A message about a missing file, or nothing happens

Why

The program was started from inside the ZIP, where it cannot find its own files.

Do this
  1. Right-click the ZIP and choose Extract All…
  2. Start SEGDMonitor.exe from the unpacked folder, and keep all its files together there

macOS

You see

“Apple could not verify…” or “cannot be opened”

Why

The build is not notarised by Apple, so macOS refuses it the first time. Needed once.

Do this
  1. Click Done
  2. Open System Settings → Privacy & Security
  3. Scroll to Security and click Open Anyway
You see

The app “is damaged and can’t be opened”

Why

The same refusal in other words: the download is marked as coming from the internet.

Do this

Clear the mark in Terminal:

xattr -cr "/Applications/SEG-D Monitor.app"
You see

Nothing happens on an Intel Mac

Why

This build is for Apple silicon (M1 or later) only.

Do this

It needs a Mac with Apple silicon. If you need an Intel build, write to us.

Linux

You see

“version `GLIBC_…' not found”

Why

Your Linux is older than this build needs - its card above says which.

Do this

See what yours has:

ldd --version

The cure is a newer system; or write to us and ask for a build for yours.

You see

“Permission denied”

Why

The program lost its permission to run when it was unpacked or copied.

Do this

Give it back:

chmod +x x_corr_app_v1_5_0.dist/segd-monitor
You see

“cannot open shared object file”

Why

A minimal installation lacks standard desktop libraries; a normal desktop one has them all.

Do this

On Ubuntu 22.04 or Debian 12, install them with the command below. On Ubuntu 24.04 write libasound2t64 for libasound2.

sudo apt install libglib2.0-0 libgl1 libegl1 libxkbcommon0 libxkbcommon-x11-0 libfontconfig1 libdbus-1-3 libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-render0 libxcb-render-util0 libxcb-shape0 libxcb-util1 libxcb-xkb1 libxrender1 libxi6 libxcomposite1 libxdamage1 libxfixes3 libxrandr2 libxtst6 libxkbfile1 libwayland-cursor0 libnss3 libnspr4 libasound2 libatomic1 libgssapi-krb5-2 libpango-1.0-0 libpangoft2-1.0-0 libharfbuzz0b

Licence

You see

“This trial licence is longer than 38 days.”

Why

The app is older than 2.26.3, the first version that takes a three-month licence.

Do this

Install the current version and load the same file again.

You see

“This license is locked to machine …”

Why

The licence was made for another machine ID.

Do this

Get one above with the ID that 🔑 License shows on this machine.

You see

“License expired on …”

Why

A free licence lasts three months.

Do this

Get the next one above, with the same machine ID and email.

Manuals

User ManualPDF · v2.28.0 · 10.2 MB Far-Field GuidePDF · v2.28.0 · 1.6 MB

What's new

Version 2.28.0

  • Shift handover (Analysis). One handover per shift: the lines shot in the shift, its gun problems and what is still open, drafted from the data. Edit it, save it, export it as a PDF. Refresh brings the data up to date and keeps the crew's notes.
  • Shifts follow the acquisition time from the SEG-D headers, so a line replayed later still lands in the shift it was shot in. Choose whether those headers are in UTC or this computer's time.
  • Drift QC. A gun slowly drifting in fire time, depth or pressure is flagged before it breaks its limit, judged against the other guns of its source, so the sea moving a whole string is not a gun fault. On by default; information only.
  • Gun Health (Analysis). Each gun's passport across lines - jitter, shots not fired, readings outside limits, drift alarms, Bubble Tests - with a score that names its reasons. Only the guns a shot asked to fire are counted, and the summaries stay when a line is deleted.

Try it on your next line.

Download it, point it at the SEG‑D folder, press Start. Free to keep - and every feature free for three months.

Download free Get the free licence