The impact of varying frame rates and bit rates on perceived quality of low/high motion sequences with smooth/complex texture

Abstract

There are evidences to indicate that a user's perception is affected by varying frame rate and bit rate with respect to different video content characteristics. We attempt to understand the differences of motion and texture characteristics by adopting both the objective assessment and the subjective assessment methodologies. In this paper, the peak signal-to-noise ratio (PSNR) is used as the objective measurement, while the double stimulus continuous quality scale (DSCQS) is used as the subjective measurement. We find that the low motion characteristic sequences suit to low frame rates while the high motion characteristic sequences suit to high frame rates under the limited bandwidths. The perceived quality of the complex texture characteristic sequences has significant difference at different bit rates. The results indicate that a multimedia scheduling system for transmitting the low motion and smooth texture (Type 1) sequences and the low motion and complex texture (Type 2) sequences should reduce frame rate to increase the bits of frame under the insufficient bandwidth, whereas the high motion and smooth texture (Type 3) sequences and the high motion and complex texture (Type 4) sequences should keep frame rate to decrease the bits of frame. The perceived quality of Type 1 and Type 3 sequences can be improved by increasing bit rate more than Type 2 and Type 4 under the limited bandwidth.