In the late ’70s and early ’80s, seismic interpretation workstations used IBM Floating-Point format. With the rise of personal computers in the mid-’80s, the IEEE format became standard—even adopted by IBM for mainframes by the late ’90s. SEG-Y Rev 1 (2002) officially supported IEEE format, yet IBM Floating-Point persists. Are there still technical benefits to using it today? The answer seems to be NO.

Here’s why across key areas:

1. Transmission
IBM float offers no advantage for data transmission. Both formats use the same storage space (32 bits), but IEEE 754 is the modern standard universally supported by software and hardware.

2. Calculation
IBM float is inefficient for modern computations. Processors are optimized for IEEE 754, meaning IBM float must be converted to IEEE for calculations. This adds unnecessary computational overhead, slowing down workflows.

3. Storage
While IBM float uses the same 32-bit size, its base-16 exponent sacrifices precision compared to IEEE 754. IEEE provides better accuracy and consistency, especially for scientific and engineering data. Converting back to IBM float for storage to comply with SEG-Y Rev 0 or other legacy standards.
This double conversion (IBM-to-IEEE and IEEE-to-IBM) introduces computational redundancy and potential for rounding errors.

Why IBM Float Persists
The only reason IBM float survives is legacy compatibility with older standards like SEG-Y Rev-0 in geophysics. SEG-Y Rev-1 and Rev-2 both support IEEE. It’s not a matter of technical superiority but historical inertia.

Conclusion
By storing data in IEEE 32-bit floating-point format and removing the need for IBM-to-IEEE and IEEE-to-IBM conversions:
Computational overhead for each dataset processing cycle can be halved (no double conversion).
The processing pipeline becomes simpler and more robust.
Resources are saved, particularly for large datasets common in geophysics.

The industry’s reliance on legacy formats poses challenges, but phased transitions or dual-format support can help. SEG-Y Rev 1 and Rev 2 already address this by supporting both formats during migration.

There’s no shortage of opinions on this topic—otherwise, we wouldn’t still be using IBM Float. Share your thoughts, experiences, or suggestions in the comments on LinkedIn.