Abstract. Three hundred and nine width measurements at various
heights to 10 m on a metal light pole were calculated from video images
captured with a prototype video-laser rangefinder instrument. Data were
captured at distances from 6 to 15 m. The endpoints for the width
measurements were manually selected to the nearest pixel from individual
video frames.
Chi-square analysis shows that 95 percent of measurements can be
expected to be within 13 mm of the actual. All errors lower than -13 mm
were on nearly horizontal images. Poor contrast causing poor edge
detection was the source of most of this error. All errors greater than 13
mm occurred between rows 280 and 390 on the image. Improper focus seemed
to be the main contributor to positive errors. Improvements to the camera
and lens system should improve these results considerably.