Multi-device lip synchronization method and device

A system, comprising a primary device and at least one secondary device;

• wherein the primary device outputs video and the at least one secondary device outputs audio;
• wherein the primary device is connected to the at least one secondary device through Wi-Fi or Bluetooth;
• wherein
• the primary device is configured to collect a program clock reference (PCR) based on a preset collection cycle;
• the primary device is configured to send a Real-Time Transport Control Protocol (RTCP) packet to each of the at least one secondary device when determining that a preset condition is met, wherein a Real-Time Transport Protocol (RTP) time stamp header field in the RTCP packet carries the PCR, and a Network Time Protocol (NTP) field in the RTCP packet carries a sending time point of the RTCP packet;
• each of the at least one secondary device is configured to receive the RTCP packet and correct a system clock (STC) of the secondary device based on the PCR, a program clock frequency of the primary device, a program clock frequency of the secondary device, and an RTCP delay;
• the primary device is configured to copy an audio data frame from an audio pulse code modulation (PCM) buffer of the primary device, pack the audio data frame into Real-Time Transport Protocols (RTPs), and publish the RTPs to a multicast service address and port, wherein a time stamp header field of the RTP carries a presentation time stamp corresponding to the audio data frame;
• each of the at least one secondary device is configured to receive RTPs, splice the RTPs into a complete audio data frame, obtain, from a time stamp header field of the RTP packet, a presentation time stamp PTS corresponding to the audio data frame, and store the audio data frame into an audio pulse code modulation (PCM) buffer of the secondary device;
• and
• each of the at least one secondary device is configured to output the audio data frame in the audio PCM buffer based on the STC of the secondary device and the presentation time stamp of the audio data frame to implement lip synchronization.

A multi-device lip synchronization method, wherein the method is applied to a primary device and at least one secondary device synchronously output video and audio, wherein the primary device outputs video and the at least one secondary device outputs audio, wherein the primary device is connected to the at least one secondary device through Wi-Fi, and the method comprises:

• receiving, by the secondary device, a Real-Time Transport Control Protocol RTCP packet sent by the primary device, wherein a Real-Time Transport Protocol RTP time stamp header field in the RTCP packet carries a program clock reference PCR cyclically collected by the primary device, and a Network Time Protocol NTP field in the RTCP packet carries a sending time point of the RTCP packet;
• correcting, by the secondary device, a system clock STC of the secondary device based on the PCR, a program clock frequency of the primary device, a program clock frequency of the secondary device, and an RTCP delay;
• receiving, by the secondary device based on a multicast service address and port sent by the primary device, RTPs published by the primary device, splicing the RTPs into a complete audio data frame, obtaining, from a time stamp header field of the RTP packet, a presentation time stamp PTS corresponding to the audio data frame, and storing the audio data frame into an audio pulse code modulation PCM buffer of the secondary device;
• and
• outputting, by the secondary device, the audio data frame in the audio PCM buffer based on the STC of the secondary device and the presentation time stamp of the audio data frame to implement lip synchronization.

A multi-device lip synchronization method, wherein the method is applied to a primary device and at least one secondary device synchronously output video and audio, wherein the primary device outputs video and the at least one secondary device outputs audio, wherein the primary device is connected to the at least one secondary device through Wi-Fi, and the method comprises:

• collecting, by the primary device, a program clock reference PCR based on a preset collection cycle;
• sending, by the primary device, a Real-Time Transport Control Protocol RTCP packet to the secondary device when determining that a preset condition is met, wherein a Real-Time Transport Protocol RTP time stamp header field in the RTCP packet carries the PCR, and a Network Time Protocol NTP field in the RTCP packet carries a sending time point of the RTCP packet, so that the secondary device corrects a system clock STC of the secondary device based on the PCR, a program clock frequency of the primary device, a program clock frequency of the secondary device, and an RTCP delay;
• and
• copying, by the primary device, an audio data frame from an audio pulse code modulation PCM buffer of the primary device, packing the audio data frame into Real-Time Transport Protocols RTPs, and publishing the RTPs to a multicast service address and port, wherein a time stamp header field of the RTP carries a presentation time stamp corresponding to the audio data frame, so that the secondary device receives the RTPs based on the multicast service address and port.