Análise da qualidade de vídeos transcodificados transmitidos por meio dos canais AWGN e Rayleigh.

Abstract

This work presents results from experiments on the quality of video signals used in digital television for mobile devices. Since the Brazilian digital television standard allows the manipulation of videos for different devices, the video signals are adapted to allow a good visualization in the use of mobile devices. These adaptations are obtained with the use of video transcoders, which are used to convert a video sequence into another with different parameters. In this work the transmission of spatially transcoded videos through AWGN and Rayleigh channels was accomplished. Seven types of filters are used for the spatial reduction of CIF (352 × 288) resolution videos to videos with QCIF (176 × 144) resolution. The measurement of objective quality PSNR was utilized to evaluate the quality of the transcoded videos.