Asynchronous Video: Coordinated Video Coding and Transport for Heterogeneous Networks with Wireless Access

Joint Source/Channel Coding to Maximize Perceptual Video Quality on Packet Networks

“…We also know that the eye acts as a spatial low-pass ®lter. From Figure 2(b), we can elicit the following sensitivity chart (Table 1) for the HVS [5]. In Table 1, we can see that HVS's sensitivity decreases as temporal frequency gets very high, so that coarse resolution for the scene is enough.…”

MPEG-compliant joint source/channel coding using discrete cosine transform and substream scheduling for visual communication over packet networks

“…Joint source/channel coding ͑JSCC͒ is a way to increase the traffic capacity of a network and also maximize a subjective image quality by exchanging some information between source coding and channel coding. [4][5][6] The multimedia data characteristics and QoS parameters can be varied with substreams ͑which we define as parts of media, for example, subblocks or subband of video/audio signal͒. If we support application of QoS with further specified substream level QoS, we can achieve more efficient QoS management.…”

“…If we support application of QoS with further specified substream level QoS, we can achieve more efficient QoS management. [4][5][6] To support the substream model for an existing frame by frame approach such as the MPEG video coding standard, we designed a simple MPEG transcoder to convert the MPEG coded stream into a series of packets. We also designed a substream scheduling scheme, which interacts with the proposed source coding scheme to maximize the perceptual video quality, and showed by simulation that our JSCC scheme is better than others.…”

Digital video in a fading interference wireless environment

“…The delay objectives of a given stream then become important, because re-laxed delay gives more flexibility to choose when to transmit each packet. Packet scheduling can be traded for traffic smoothing and greater statistical multiplexing advantage on wireless access links [9].…”