Hardware and software specification covers requirements for using subroutines to improve structural weld photographs

Thomas, D. T.

English

NASA Technical Reports Server

December 1971	 Brief 71-10492 
NASA TECH BRIEF 
Marshall Space Flight Center
	
_ilv 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the. Tech Brief program may 
be directed to the Technology. Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
Optimized Techniques and Requirements for Computer

Improvement of Structural Weld Radiographs 
The problem: 
Because of the physical limitations of radiography, 
the primary tool for weld analyses, unsharp images 
can be produced, creating a possibility for error in 
reading the nature of the image. The detection of 
cracks and crack-like defects, such as porosity 
with a sharp tail, porosity connected by a crack, 
lack of sidewall fusion, and the complete penetra-
tion of two weld beads in plate material welded from 
both sides, has become imperative because of the 
low safety factors inherent in present technological 
programs such as the manned space mission. 
The solution: 
A recent study resulted in a hardware and soft-
ware specification covering the requirements for 
using a computer to improve structural weld photo-
graphs. 
How it's done: 
Three scanning systems were used to digitize more 
than 15 weld radiographs. The performance of 
these systems was evaluated by determining modula-
tion transfer functions and noise characteristics. 
Enhancement techniques were developed and applied 
to the digitized radiographs. The scanning param-
eters of spot size and spacing, and film density, were 
studied to optimize the information content of the 
digital representation of the image. Hardware re-
quirements for an X-ray enhancement system were 
determined, and the system configuration was 
specified. 
Notes: 
1. The subroutines were written in FORTRAN IV 
for use under the VICAR image processing sys-
tem. 
2. These subroutines are available only as listings 
contained in the documentation. 
3. Requests for further information may be directed 
to:
COSMIC 
112 Barrow Hall 
University of Georgia 
Athens, Georgia 30601 
Reference: B71-10492 
Patent status: 
No patent action is contemplated by NASA. 
Source: D. T. Thomas

Marshall Space Flight Center

(MFS-21627) 
Category 09 
This documett was prepared under the sponsorship of the National 
Aeronautics and Space Administration. Neither the United States 
Government nor any person acting on behalf of the United States
Government assumes any liability resulting from the use of the 
information contained in this document, or warrants that such use 
will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19710000489 2020-03-17T02:26:38+00:00Z


Optimized techniques and requirements for computer improvement of structural weld radiographs

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