Implementación de un sistema de codificación de vídeo con descripción múltiple mediante submuestreo espacial polifase

En este TFC se debe implementar un codificador de vídeo de descripción múltiple. El codificador toma una secuencia de vídeo en formato YUV y sobre cada imagen realiza un submuestreo espacial para obtener K descriptores que se codificarán vía un codec SD como, por ejemplo, MPEG4 o H.264. Igualmente se deberá implementar la parte descodificadora que tomando cada uno de estos descriptores los descodificará mediante el codec SD y a partir de ellos reconstruirá la secuencia original haciendo una interpolación frame a frame. Finalmente, se aplica un filtro que mejorará la PSNR final. Una parte importante del TFC lo constituyen las pruebas que cuantifiquen la calidad del sistema implementado

MDC AND PATH DIVERSITY IN VIDEO STREAMING

Delivering multimedia content over the network pose several challenges that include higher bandwidth and sensitivity to packet losses resulting due to congestion and/or transmission errors. Multiple description coding (MDC) is one of the source coding approaches to alleviate the problems of packet loss in a network since MDC splits the source information into several descriptions which can then be transmitted over several paths in the network. Parallel delivery of descriptions over multiple paths should guarantee better quality of transmission. In this paper we investigate the performance of a generalized MDC scheme over multi-path and single path scenarios and compare its performance to a layered single description (SDC) scheme. In the multi-path case multimedia content is delivered via k-shortest paths that are selected on the basis of the packet loss probability of overall links in that path. Our experimental results show that MDC scheme always outperforms the SDC scheme in terms of PSNR quality for both single and multi-path transmissions. The improvement varies from 7dB at (5 % packet loss) to 13dB at (20 % packet loss) for the single path and by 3dB to 9dB respectively for the multi-path transmission