Compressed video buffering

Patent metadata

Field	Value
Publication number	US-2016295254-A1
Application number	US-201615082580-A
Country	US
Kind code	A1
Filing date	Mar 28, 2016
Priority date	Mar 31, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

A system controls a transmission of a sequence of compressed video data from an encoder buffer to a network for delivery to a decoder buffer. Control of the transmission includes to: determine characteristics of a video transmission path between the encoder buffer and the decoder buffer, the characteristics comprising at least one of a buffer size of the decoder buffer, an input rate of the decoder buffer, and a buffer size of an equivalent intermediary buffer of the video transmission path; determine a transmission rate from the characteristics of the video transmission path and from the sequence of compressed video data, the transmission rate being determined such that a target quality of service value can be guaranteed for the entire sequence of compressed video data transmitted at the determined transmission rate to the decoder buffer; and control transmission of the sequence of compressed video data at the determined transmission rate.

First claim

1 . A system, comprising: circuitry configured to control a transmission of a sequence of compressed video data from an encoder buffer to a network for delivery to a decoder buffer, wherein control of the transmission includes to:
determine characteristics of a video transmission path between the encoder buffer and the decoder buffer, the characteristics comprising at least one characteristic selected from the group comprising a buffer size of the decoder buffer, an input rate of the decoder buffer, and a buffer size of an equivalent intermediary buffer of the video transmission path; determine a transmission rate from the characteristics of the video transmission path and from the sequence of compressed video data, the transmission rate being determined such that a target quality of service value can be guaranteed for the entire sequence of compressed video data transmitted at the determined transmission rate to the decoder buffer; and control transmission of the sequence of compressed video data at the determined transmission rate.

2 . The system of claim 1 , wherein the network is an internet protocol network.

3 . The system of claim 1 , wherein the transmission of the sequence of compressed video data is a transmission of streaming video, and the transmission rate is independent of network delay and jitter in the video transmission path.

4 . The system of claim 1 , wherein the characteristics include a latency of the video transmission path.

5 . The system of claim 1 , wherein the characteristics include a jitter of the video transmission path.

6 . The system of claim 1 , wherein the characteristics include a number of intermediary nodes in the video transmission path.

7 . The system of claim 1 , wherein the target quality of service value ensures that the compressed video data in the decoder buffer will not overflow.

8 . The system of claim 1 , wherein the target quality of service value ensures that the compressed video data in the decoder buffer will not underflow.

9 . The system of claim 1 , wherein the target quality of service is related to burstiness of a video stream in the video transmission path.

10 . The system of claim 1 , wherein the transmission of the compressed video data from the encoder buffer through the network interface to the network is either a unicast transmission or a multicast transmission.

11 . A method, comprising:
determining, in a video source equipment, a transmission rate for compressed video data that is sufficient to avoid underflow and overflow of a decoder buffer in a memory of a receiver of a distribution path, the distribution path being between the encoder buffer and the decoder buffer, the determining comprising:
identifying a combined amount of compressed video data of an encoder buffer of the video source equipment, the total amount including a first amount of compressed video data presently in the encoder buffer and a second amount of compressed video data to be provided to the encoder buffer;
identifying a third amount of compressed video data presently in at least one intermediary buffer in the distribution path;
calculating an expected amount of data to be received at the decoder buffer over a time interval;
ensuring that the combined amount of compressed video data plus the third amount of compressed video data is greater than or equal to the expected amount of data to be received at the decoder buffer; and
ensuring that the expected amount of data to be received at the decoder buffer minus the first amount of compressed video data presently in the encoder buffer and minus the third amount of compressed video data presently in the at least one intermediary buffer is less than or equal to a maximum size of the decoder buffer; and
transmitting the compressed video data at the determined rate from a transmitter of the video source.

12 . The method of claim 11 , wherein the expected amount of data to be received at the decoder buffer over the time interval is equal to a data rate for an input to the decoder integrated from a first time instant to an expected start of extracting the second amount of compressed video data from the decoder buffer.

13 . The method of claim 12 , wherein the first time instant is an expected start of providing the second amount of compressed video data to the encoder buffer.

14 . The method of claim 12 , wherein the first time instant is an expected start of providing the second amount of compressed video data to the encoder buffer plus a constant network delay.

15 . The method of claim 12 , wherein the first time instant is an expected start of providing the second amount of compressed video data to the encoder buffer plus a constant network delay plus a maximum expected network jitter.

16 . The method of claim 11 , further comprising adjusting the determined transmission rate to compensate for a network jitter in the distribution path.

17 . The method of claim 16 , wherein compensating for a network jitter in the distribution path is compensating in a dejitter buffer of the video source equipment.

18 . The method of claim 11 , wherein the distribution path is modeled as a (ρ, b) regulator having a token depth b, wherein the token depth b is greater than or equal to a largest size of a compressed frame within a sequence to be transferred in the time interval minus a product, where the product is a ratio of a constant rate of filling the regulator with tokens of a fixed size multiplied by a transmission time to transmit a maximum sized frame of the sequence.

19 . The method of claim 19 , wherein determining the transmission rate comprises calculating a maximum value of a plurality of average frame transmission rates, wherein each average frame transmission rate represents a window of a defined number of consecutive compressed frames in the sequence, and the window is a sliding window over the sequence.

20 . An apparatus, comprising:
at least one memory comprising a video encoder data buffer; transmitter circuitry configured to provide data from the encoder data buffer to a distribution path and directed to a receiver in the distribution path; and processor circuitry configured to:
determine a transmission rate for compressed video data to be transmitted by the transmitter, the transmission rate determined to ensure that a decoder buffer of the receiver will not underflow or overflow during transmission of a defined length video sequence to the receiver;
provide the determined transmission rate to network nodes in the distribution path for quality of service provisioning; and
control the transmitter circuitry to transmit the video sequence at the determined transmission rate.

21 . The apparatus of claim 20 , wherein a decoder buffer size of the decoder buffer of the receiver is equal to a maximum output data rate of the encoder buffer multiplied by a sum of: a maximum jitter of the distribution path, and a time interval between placing a frame of the video sequence in the encoder buffer and removing the frame from the decoder buffer.

22 . The apparatus of claim 21 , wherein the determined transmission rate is equal to a maximum of a plurality of average frame sizes divided by the time interval, wherein each average frame size is an average of frame sizes in a predefined size of window, and the window is a sliding window over the video sequence.

23 . The apparatus of claim 20 , wherein the distribution path is modeled as a (ρ, b) regulator, and t

Assignees

• Broadcom Corp

Inventors

• Chen Xuemin
• Li Gordon

Classifications

• H04N21/23406 Primary

  involving management of server-side video buffer · CPC title

• H04N19/152

  by measuring the fullness of the transmission buffer · CPC title

• H04N21/2408

  Monitoring of the upstream path of the transmission network, e.g. client requests (monitoring data switching networks utilization H04L43/0876; scheduling or organising the servicing of application requests H04L67/60) · CPC title

• H04N21/2662

  Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities · CPC title

• H04N21/6125

  involving transmission via Internet (transmission by internet of broadcast information H04H60/82) · CPC title