1 October 2010 Visual acuity, contrast sensitivity, and range performance with compressed motion video
Author Affiliations +
Abstract
Video of visual acuity (VA) and contrast sensitivity (CS) test charts in a complex background was recorded using a CCD color camera mounted on a computer-controlled tripod and was fed into real-time MPEG-2 compression/decompression equipment. The test charts were based on the triangle orientation discrimination (TOD) test method and contained triangle test patterns of different sizes and contrasts in four possible orientations. In a perception experiment, observers judged the orientation of the triangles in order to determine VA and CS thresholds at the 75% correct level. Three camera velocities (0, 1.0, and 2.0 deg/s, or 0, 4.1, and 8.1 pixels/frame) and four compression rates (no compression, 4 Mb/s, 2 Mb/s, and 1 Mb/s) were used. VA is shown to be rather robust to any combination of motion and compression. CS, however, dramatically decreases when motion is combined with high compression ratios. The measured thresholds were fed into the TOD target acquisition model to predict the effect of motion and compression on acquisition ranges for tactical military vehicles. The effect of compression on static performance is limited but strong with motion video. The data suggest that with the MPEG2 algorithm, the emphasis is on the preservation of image detail at the cost of contrast loss.
© (2010) Society of Photo-Optical Instrumentation Engineers (SPIE)
Piet Bijl, Piet Bijl, Sjoerd C. de Vries, Sjoerd C. de Vries, } "Visual acuity, contrast sensitivity, and range performance with compressed motion video," Optical Engineering 49(10), 103203 (1 October 2010). https://doi.org/10.1117/1.3503950 . Submission:
JOURNAL ARTICLE
8 PAGES


SHARE
RELATED CONTENT

Disparity estimation and disparity-coherent watermarking
Proceedings of SPIE (March 03 2015)
Indexing of compressed video sequences
Proceedings of SPIE (March 12 1996)
Light field video camera
Proceedings of SPIE (December 19 2001)

Back to Top