IP packet compression, decompression method for mobile multimedia broadcast system

Abstract

The invention provides a method for compressing and decompressing an IP packet of a mobile multimedia broadcasting system. The compressing method comprises the following steps: a stable field of the IP packet is removed from an initial IP packet of a service flow to be transmitted to generate a compressed IP packet; a session environment information table containing the stable field and identification of the session environment information table is transmitted in a control logic channel of the mobile multimedia broadcasting system; and the compressed IP packet is encapsulated in a radio broadcasting multiplex packet containing the identification of the session environment information table, and is transmitted in a service logic channel of the mobile multimedia broadcasting system, wherein the stable field of the IP packet is a data packet header field remained in a plurality of continuous initial IP packets of the service flow to be transmitted. The method for compressing and decompressing the IP packet has a simple realization mode, is applicable to compression and decompression of IP packets with various load formats, ensures that the IP packet has high compression efficiency and reliability, and can effectively reduce processing burden and electricity consumption of an embedded receiving terminal with strain hardware and software resources.

Description

technical field [0001] The invention relates to an IP (Internet Protocol, Internet Protocol) packet compression and decompression method of a mobile multimedia broadcasting system. Background technique [0002] In recent years, digital wireless mobile multimedia broadcasting technologies and standards have developed rapidly, such as DVB-H (Digital Video Broadcast Handheld, digital video broadcasting handheld reception) in Europe, and MediaFLO (Media Forward Link Only, media single forward link) in the United States. And China's CMMB (China Mobile Multimedia Broadcasting, mobile multimedia broadcasting) and so on. [0003] The mobile multimedia broadcasting system can provide video and audio services for mobile terminal users, and can also provide a variety of data broadcasting services, such as video clip files based on file download mode, MP3 (MPEG Audio Layer 3, Motion Picture Experts Group Audio Layer 3) Songs, services based on real-time data streams, such as traffic in...

AI Technical Summary

Problems solved by technology

[0018] (1) When the front end of the system is compressing and encoding, it needs to periodically send session environment data packets such as FULL_HEADER packets, and for each RTP compressed packet, it is also necessary to calculate the time stamp difference; and when the terminal decompresses, it needs to maintain a Complex state machine, which performs parameter update and state jump according to the received session environment data packets, and the implementation of compressor and decompressor is relatively complicated, which is not suitable for implementation on embedded terminals with tight system software and hardware resources such as mobile phones

[0019] (2) The CMMB mobile multimedia broadcast channel is a one-way broadcast link, and the terminal cannot perform real-time data interaction with the system front end

Its fatal weakness is that even if there is an error in receiving a data packet, such as packet loss due to a link error code, resulting in a wrong serial number of the received packet or an unrecoverable timestamp, it may be necessary to restore the decompression (receive a new uncompressed Before the IP header) discard a large number of packets

For the terminal, a large amount of packet loss will cause severe interruption of audio and video

If you only rely on the method of increasing the periodic refresh frequency to reduce the occurrence of the above problems, it will inevitably affect the transmission efficiency of data packets

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