Clock Recovery via PCR Extraction from Transport Stream
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Solution Overview
Problem
Existing clock recovery processing methods for intermittently transmitted broadcasting TS suffer from high circuit costs and increased memory bus load due to the need for buffering, leading to delays in processing and elevated PCR jitter.
Innovation Solution
An information processing apparatus that extracts time information from a data stream, stores it, and outputs it synchronously with the system clock signal based on transmission rate and position information, allowing for efficient clock recovery processing without buffering the entire data stream.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the TS is buffered in units of frames using an N:M frequency divider, then the PCR jitter is suppressed and clock recovery stability is improved, but the circuit costs increase due to memory requirements
Solution Approach 1:
The patent extracts only the necessary time information (PCR values and position information) from the transport stream, rather than buffering the entire stream. This extraction approach maintains clock recovery stability while eliminating the need for large buffer memories, thus reducing circuit complexity and costs.
Solution Approach 2:
The patent segments the time information extraction and processing into distinct components: extracting PCR values, storing position information, and controlling output timing separately. This segmentation allows efficient processing without requiring comprehensive buffering of the entire transport stream, reducing overall system complexity.
2Reliability
If the TS is buffered one time, then the PCR jitter is suppressed, but a delay time occurs until the next processing such as decode processing
Solution Approach 1:
The patent performs preliminary extraction and storage of time information (PCR values and position information) as the transport stream is received. This preliminary action allows the time information to be ready for immediate use in clock recovery without waiting for buffer completion, thus suppressing PCR jitter while minimizing processing delay.
Solution Approach 2:
The patent applies different processing treatments to different parts of the data: time information is extracted and stored for immediate clock recovery use, while the main transport stream continues to be processed for decoding. This local quality approach ensures jitter suppression for timing-critical operations without introducing delays to the overall processing pipeline.
3Reliability
If the TS is buffered in units of frames, then the clock recovery processing is stabilized, but the load on the memory bus increases
Solution Approach 1:
The patent extracts only the essential time information (PCR values and position data) from the transport stream for buffer storage, rather than buffering the entire stream. This extraction significantly reduces the volume of data that needs to be transferred over the memory bus, thereby reducing memory bus load while maintaining clock recovery stability.
Solution Approach 2:
The patent segments the data processing into two paths: time information is extracted and stored in a small buffer for clock recovery, while the main transport stream is processed separately for decoding. This segmentation reduces memory bus traffic by handling only the critical timing data through the buffer, lowering overall memory bus load.
Data Source
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AI summary
In a case in which a data stream including time information is received and clock recovery processing is performed, the present technology relates to an information processing apparatus, an information processing method, and a program that aim at enabling the clock recovery processing to be performed efficiently and stably. In the information processing apparatus according to an aspect of the present technology, time information is extracted from a data stream including the time information serving as a reference when generating a system clock signal, and the time information is stored in a storage section. Further, the time information stored in the storage section is output synchronously with the system clock signal on the basis of a transmission rate of the data stream and position information regarding the time information in the data stream, and the clock recovery processing is performed on the basis of the time information output from the storage section and the system clock signal is generated. The present technology is applicable to a receiver of digital broadcasting.