Low-delay real-time transport stream multiplexing method

Abstract

The invention provides a low delay method for multiplexing a transport stream in real time, which includes the steps: audio-video basic data is packed into a packing elementary stream PES; then, the PES is packed into a TS packet; PSI data of program specific information is generated; after the PES packing and the TS packing of ES data of frame video and ES data of the audio in the corresponding time are completed, an audio TS packet and a video TS packet are uniformly put into a buffer output by the transport stream and at the same time reference PCR information of a program clock is updated; when the multiplexing of a video ES stream of a GOP, according to transmission rate of the transport stream and data quantity of the GOP, an empty packet is filled in the output buffer to output the transport stream with constant bit rate. The method has constant transmission rate, reduce the delay and capacity of the buffer.

Description

technical field [0001] The invention belongs to the technical field of audio and video encoding and decoding in signal processing, and in particular relates to a low-delay real-time multiplexing transmission stream method. Background technique [0002] Digital audio and video codec standards have developed rapidly, and MPEG-2 has been maturely applied; in recent years, a number of representative audio and video standards have emerged: international standards such as MPEG-4, H.264 / MPEG-4 AVC, and my country's self-developed standard AVS and so on. There is a system part in these standards, called the system layer, which mainly stipulates how to combine single or multiple basic audio and video streams and other data into single and multiple composite streams suitable for storage and transmission. A transport stream is a data stream defined by the system layer, which combines one or more programs with one or more different clock bases into a single stream, and its rate can be c...

AI Technical Summary

Problems solved by technology

Therefore, in the process of multiplexing the video ES stream into a transport stream, if the bandwidth is allocated according to the maximum peak value (I frame code rate), then most of the time code rates in the transport stream are less than the peak value, resulting in a waste of channel resources; rate allocation channel bandwidth, the buffer needs to be used to absorb the part of the maximum peak value exceeding the average value before multiplexing. When multiple programs are multiplexed, the capacity of the buffer must be large, as shown in Figure 1, thereby increasing the transmission delay

Moreover, the peak code rate, that is, the code rate of the I frame appears for a short time, and the average code rate allocation reduces the use efficiency of the buffer.

At present, there are some algorithms to solve this problem. For example, the frame shifting method is a simple and effective method to solve this problem for the multiplexing of transport streams containing multiple programs. However, the frame shifting method cannot solve the multiplexing of transport streams of single-channel programs. use question

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