TY - GEN
T1 - Evaluating quality and comprehension of real-time sign language video on mobile phones
AU - Tran, Jessica J.
AU - Kim, Joy
AU - Chon, Jaehong
AU - Riskin, Eve A.
AU - Ladner, Richard E.
AU - Wobbrock, Jacob O.
PY - 2011
Y1 - 2011
N2 - Video and image quality are often objectively measured using peak signal-to-noise ratio (PSNR), but for sign language video, human comprehension is most important. Yet the relationship of human comprehension to PSNR has not been studied. In this survey, we determine how well PSNR matches human comprehension of sign language video. We use very low bitrates (10-60 kbps) and two low spatial resolutions (192×144 and 320×240 pixels) which may be typical of video transmission on mobile phones using 3G networks. In a national online video-based user survey of 103 respondents, we found that respondents preferred the 320×240 spatial resolution transmitted at 20 kbps and higher; this does not match what PSNR results would predict. However, when comparing perceived ease/difficulty of comprehension, we found that responses did correlate well with measured PSNR. This suggests that PSNR may not be suitable for representing subjective video quality, but can be reliable as a measure for comprehensibility of American Sign Language (ASL) video. These findings are applied to our experimental mobile phone application, MobileASL, which enables real-time sign language communication for Deaf users at low bandwidths over the U.S. 3G cellular network.
AB - Video and image quality are often objectively measured using peak signal-to-noise ratio (PSNR), but for sign language video, human comprehension is most important. Yet the relationship of human comprehension to PSNR has not been studied. In this survey, we determine how well PSNR matches human comprehension of sign language video. We use very low bitrates (10-60 kbps) and two low spatial resolutions (192×144 and 320×240 pixels) which may be typical of video transmission on mobile phones using 3G networks. In a national online video-based user survey of 103 respondents, we found that respondents preferred the 320×240 spatial resolution transmitted at 20 kbps and higher; this does not match what PSNR results would predict. However, when comparing perceived ease/difficulty of comprehension, we found that responses did correlate well with measured PSNR. This suggests that PSNR may not be suitable for representing subjective video quality, but can be reliable as a measure for comprehensibility of American Sign Language (ASL) video. These findings are applied to our experimental mobile phone application, MobileASL, which enables real-time sign language communication for Deaf users at low bandwidths over the U.S. 3G cellular network.
KW - american sign language
KW - bitrate
KW - deaf community
KW - mobile phones
KW - online survey
KW - psnr
KW - spatial resolution
KW - video compression
UR - http://www.scopus.com/inward/record.url?scp=81855167412&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=81855167412&partnerID=8YFLogxK
U2 - 10.1145/2049536.2049558
DO - 10.1145/2049536.2049558
M3 - Conference contribution
AN - SCOPUS:81855167412
SN - 9781450309196
T3 - ASSETS'11: Proceedings of the 13th International ACM SIGACCESS Conference on Computers and Accessibility
SP - 115
EP - 122
BT - ASSETS'11
T2 - 13th International ACM SIGACCESS Conference on Computers and Accessibility, ASSETS'11
Y2 - 24 October 2011 through 26 October 2011
ER -