ANALYSIS OF IMAGE DEFINITION

TECHNIQUES BY WHICH THE PHOTO-INTERPRETER OR PHOTOGRAMMETRIST CAN EVALUATE THE CLARITY OF MICRO-DETAIL IN AERIAL PHOTOGRAPHS ARE NEEDED, AND A COMPARISON OF PANCHROMATIC, INFRARED, COLOR AND COLOR INFRARED AIR SURVEY PHOTOGRPHS INDICATES LINKING OF BOTH VISUAL AND QUANTITATIVE METHODS IS DESIRABLE. VISUAL EVALUATION, FOR EXAMPLE, IS NECESSARY TO ESTABLISH THE THRESHOLD OF DETECTION FOR LOW CONTRAST OBJECTS. A QUANTITATIVE ANALYSIS, HOWEVER, DOES NOT DETERMINE THE LIMITS OF VISUAL DETECTION, BUT CAN BRING OUT THE RELATIVE IMPORTANCE OF FACTORS SUCH AS LENS ABERRATIONS, RESOLUTIONS, GRANULARITY, IMAGE MOTION AND BOTH OBJECT AND IMAGE CONTRAST. THESE, WHEN LINKED WITH KNOWN PARAMETERS SUCH AS LENS-FILM CHARACTERISTICS AND AIRCRAFT SPEED, PROVIDE INFORMATION WHICH INDICATES THE TYPE OF PHOTOGRAPHIC SYSTEM NECESSARY TO FULFILL VISUAL REQUIREMENTS IN TERMS OF SMALLEST DETECTABLE OBJECTS. IF BOTH VISUAL AND QUANTITATIVE DATA WERE COMPILED FOR OPERATIONAL PHOTOGRAPHY OVER A PERIOD OF TIME, SUFFICIENT INFORMATION FOR THE ESTABLISHMENT OF STANDARDS WOULD SOON BE OBTAINED. MORE RELIABLE PREDICTIONS COULD THEN BE MADE CONCERNING THE MINIMUM SIZES OF OBJECTS LIKELY TO BE DETECTED OR MEASURED ON PHOTOGRAPHS OBTAINED WITH DIFFERENT SYSTEMS UNDER GIVEN CONDITIONS. /PE/

  • Supplemental Notes:
    • Vol 35, Nov 12, PP 1228-1238, 6 FIG, 5 TAB, 28 REF
  • Authors:
    • Welch, R
  • Publication Date: 1969-12

Media Info

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Filing Info

  • Accession Number: 00202814
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 4 1970 12:00AM