公开(公告)号：US20150049248A1

公开(公告)日：2015-02-19

申请号：US14262994

申请日：2014-04-28

Applicant: QUALCOMM Incorporated

Inventor： Min Wang ,  Tien-Hsin Lee ,  Shankar Genesh LakshmanaSwamy ,  Andy Yu ,  Vikram Singh ,  Sandeep Padubidri Ramamurthy ,  Yau Mo Chan ,  Vasudev Sujir Nayak ,  Srinivasan Balasubramanian

IPC: H04L29/06 ,  H04N5/04

CPC classification number: H04L65/602 ,  H04J3/00 ,  H04L65/607 ,  H04L65/608 ,  H04L69/28 ,  H04N5/04 ,  H04N21/6437 ,  H04N21/8547

Abstract: Methods, systems, and devices are described for media synchronization. Multi-stream media processes may include media streams captured with respect to different clock rates. Multi-processor implementations may involve separate clocks associated with different media streams, such as audio and video, respectively. The separate clocks may tend to drift from one another, becoming further out of sync as time passes. Selecting a reference time of one of the processors to function as a “wall clock,” recording frame capture times with respect to the reference time, accounting for propagation delays, and transmitting frame capture times in terms of the reference time may aid in AV synchronization at a device where audio and video streams are received.

Abstract translation: 描述了媒体同步的方法，系统和设备。 多流媒体处理可以包括关于不同时钟速率捕获的媒体流。 多处理器实现可以分别涉及与不同媒体流（例如音频和视频）相关联的单独的时钟。 单独的时钟可能趋向于彼此漂移，随着时间的过去而变得更加不同步。 选择其中一个处理器作为“挂钟”的参考时间，相对于参考时间记录帧捕获时间，考虑传播延迟和根据参考时间传输帧捕获时间可以有助于AV同步 在接收音频和视频流的设备上。

公开(公告)号：US20170373881A1

公开(公告)日：2017-12-28

申请号：US15631807

申请日：2017-06-23

Applicant: QUALCOMM Incorporated

Inventor： Andy Yu ,  Andrew Cheung ,  Ameya Kulkarni

IPC: H04L12/40 ,  H04L12/931 ,  H04L12/28

Abstract: Systems and methods for controlling isochronous data streams are disclosed. Particular aspects of the present disclosure are designed to be used with almost any isochronous data stream, but are well-suited for use with the Universal Serial Bus (USB) protocol. Further, aspects of the present disclosure are flexible to accommodate existing configuration possibilities within the USB protocol as well as accommodate proposed future changes in the USB protocol. The flexibility of the systems and methods is provided by calculating: (1) drift between a USB host system time and the application and (2) drift between the USB host system and a USB device clock. Based on these two drift calculations, a time stamp may be synthesized to program a next delivery schedule. Using this time stamp, jitter correction can take place and uniformly-sized packets may be assembled to pass to an application processor.

公开(公告)号：US09300713B2

公开(公告)日：2016-03-29

申请号：US14262994

申请日：2014-04-28

Applicant: QUALCOMM Incorporated

Inventor： Min Wang ,  Tien-Hsin Lee ,  Shankar Genesh LakshmanaSwamy ,  Andy Yu ,  Vikram Singh ,  Sandeep Padubidri Ramamurthy ,  Yau Mo Chan ,  Vasudev Sujir Nayak ,  Srinivasan Balasubramanian

IPC: H04L29/06 ,  H04N5/04 ,  H04J3/00 ,  H04N21/6437 ,  H04N21/8547

CPC classification number: H04L65/602 ,  H04J3/00 ,  H04L65/607 ,  H04L65/608 ,  H04L69/28 ,  H04N5/04 ,  H04N21/6437 ,  H04N21/8547

Abstract: Methods, systems, and devices are described for media synchronization. Multi-stream media processes may include media streams captured with respect to different clock rates. Multi-processor implementations may involve separate clocks associated with different media streams, such as audio and video, respectively. The separate clocks may tend to drift from one another, becoming further out of sync as time passes. Selecting a reference time of one of the processors to function as a “wall clock,” recording frame capture times with respect to the reference time, accounting for propagation delays, and transmitting frame capture times in terms of the reference time may aid in AV synchronization at a device where audio and video streams are received.

Abstract translation: 描述了媒体同步的方法，系统和设备。 多流媒体处理可以包括关于不同时钟速率捕获的媒体流。 多处理器实现可以分别涉及与不同媒体流（例如音频和视频）相关联的单独的时钟。 单独的时钟可能趋向于彼此漂移，随着时间的过去而变得更加不同步。 选择其中一个处理器作为“挂钟”的参考时间，相对于参考时间记录帧捕获时间，考虑传播延迟和根据参考时间传输帧捕获时间可以有助于AV同步 在接收音频和视频流的设备上。