Are PCR measurements critical?
A program clock reference (PCR) enables the MPEG decoder to synchronize to the encoder. The system time clock is locked to the stream PCRs. A 42-bit sample of the sine-wave of the system time clock at the encoder indicates to the demultiplexer what the clock’s time should be at the decoder when each clock reference is received. Synchronization errors arise if the PCR value generated by the multiplexer is inaccurate, or if it is received late because of network delays, such as jitter.
