Synchronizing content and control signals using jitter buffer
A device, which is part of a decentralized media playout system, is located at a destination location. The device includes a processor, memory, a network interface, and a jitter buffer implemented in the memory. The jitter buffer buffers programming content and control messages, which are received from a source location of the decentralized media playout system, before transmitting them to a mixer. A first relative timing relationship between the programming content and the control messages exists at the source location, and a second, altered relative timing relationship between the programming content and the control messages exists at the destination location. The processor restores the first relative timing relationship between the programming content and the control messages, as it existed at the source location, by instructing the jitter buffer to delay transmitting either the programming content or the control messages to the mixer.
1. A device, located at a destination location of a decentralized media playout system, the device comprising:
a processor;
memory coupled to the processor, the memory storing a common sequence of media items pre-distributed to a plurality of dispersed locations of the decentralized media playout system;
a network interface coupled to the memory and the processor, wherein the network interface receives studio programming content and control messages from a source location of the decentralized media playout system subsequent to storing the common sequence of media items;
a jitter buffer implemented in the memory, and configured to buffer the studio programming content and the control messages received from the source location of the decentralized media playout system, before transmitting the studio programming content-and the control messages to a mixer, wherein:
a first relative timing relationship among the studio programming content, the control messages, and the common sequence of media items exists at the source location;
a second relative timing relationship among the studio programming content, and the control messages, and the common sequence of media items exists at the destination location; and
the second relative timing relationship is altered from the first relative timing relationship; and
the processor configured to restore the first relative timing relationship among the studio programming content, the control messages, and the common sequence of media items as it existed at the source location by instructing the jitter buffer to delay transmitting to the mixer at least one of the studio programming content or the control message.
2. The device of claim 1 , wherein:
the processor is further configured to instruct the jitter buffer to insert a static amount of delay before transmitting the at least one of the studio programming content or the control messages from the jitter buffer to the mixer.
3. The device of claim 1 , wherein:
the processor is further configured to instruct the jitter buffer to dynamically delay transmission of the at least one of the studio programming content or the control messages from the jitter buffer to the mixer based on varying network conditions.
4. The device of claim 1 , wherein:
the processor is further configured to instruct the jitter buffer to delay transmission of the at least one of the studio programming content or the control messages from the jitter buffer to the mixer based a difference between a first arrival time of a particular item of the studio programming content and a second arrival time of a particular control message.
5. The device of claim 1 , wherein:
the processor is further configured to determine an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on information included in message headers.
6. The device of claim 5 , wherein:
the processor is further configured to determine an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on training fields included in the message headers.
7. The device of claim 1 , wherein:
the processor is further configured to determine an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on time stamps included in the control messages.
8. A method for use in a device located at a destination location of a decentralized media playout system, the method comprising:
storing a common sequence of media items pre-distributed to a plurality of dispersed locations of the decentralized media playout system
subsequent to storing the common sequence of media items, receiving studio programming content and control messages from a source location of the decentralized media playout system;
buffering the studio programming content and the control messages in a jitter buffer prior to transmitting the studio programming content and the control messages to a mixer, wherein:
a first relative timing relationship among the studio programming content, the control messages, and the common sequence of media items exists at the source location;
a second relative timing relationship among the studio programming content, the control messages, and the common sequence of media items exists at the destination location; and
the second relative timing relationship is altered from the first relative timing relationship; and
restoring the first relative timing relationship among the studio programming content, the control messages, and the common sequence of media items as it existed at the source location by delaying transmission of at least one of the studio programming content or the control message from the jitter buffer to the mixer.
9. The method of claim 8 , further comprising:
inserting, by the jitter buffer, a static amount of delay before transmitting the at least one of the studio programming content or the control messages from the jitter buffer to the mixer.
10. The method of claim 8 , further comprising:
dynamically delaying transmission of the at least one of the studio programming content or the control messages from the jitter buffer to the mixer based on varying network conditions.
11. The method of claim 8 , further comprising:
delaying transmission of the at least one of the studio programming content or the control messages from the jitter buffer to the mixer based on a difference between a first arrival time of a particular item of the studio programming content and a second arrival time of a particular control message.
12. The method of claim 8 , further comprising:
determining an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on information included in message headers.
13. The method of claim 12 , further comprising:
determining an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on training fields included in the message headers.
14. The method of claim 8 , further comprising:
determining an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on time stamps included in the control messages.
15. A decentralized media playout system including a source location and
a destination location, the decentralized media playout system comprising:
a first device at the source location, wherein:
a first processor;
first memory coupled to the first processor, the first memory storing a common sequence of media items pre-distributed to both the source location and the destination location;
a network interface coupled to the first memory and the first processor, wherein the network interface is configured to transmit studio programming content and control messages to the destination location, wherein a first relative timing relationship among the studio programming content the control messages, and the common sequence of media items exists at the source location;
a second device at the destination location, the second device including:
a second processor;
second memory coupled to the second processor, the second memory storing the common sequence of media items pre-distributed to both the source location and the destination location;
a second network interface coupled to the second memory and the second processor configured to receive the studio programming content and the control messages from the source location;
a jitter buffer implemented in the second memory, and configured to buffer the studio programming content and the control messages before transmitting the studio programming content and the control messages to a mixer, wherein:
a second relative timing relationship among the studio programming content, the control messages exists at the destination location; and
the second relative timing relationship is altered from the first relative timing relationship; and
the second processor configured to restore the first relative timing relationship among the studio programming content, the control messages, and the common sequence of media items as it existed at the source location by instructing the jitter buffer to delay transmitting to the mixer one of the studio programming content or the control message.
16. The decentralized media playout system of claim 15 , wherein:
the second processor is further configured to instruct the jitter buffer to insert a static amount of delay before transmitting the at least one of the studio programming content or the control messages from the jitter buffer to the mixer.
17. The decentralized media playout system of claim 15 , wherein:
the second processor is further configured to instruct the jitter buffer to dynamically delay transmission of the at least one of the studio programming content or the control messages to the mixer based on varying network conditions.
18. The decentralized media playout system of claim 15 , wherein:
the second processor is further configured to instruct the jitter buffer to delay transmission of the at least one of the studio programming content or the control messages to the mixer based on a difference between a first arrival time of a particular item of the studio programming content and a second arrival time of a particular control message.
19. The decentralized media playout system of claim 15 , wherein:
the second processor is further configured to determine an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on information included in message headers.
20. The decentralized media playout system of claim 15 , wherein:
the second processor is further configured to determine an amount by which the second relative timing relationship has been altered from the first relative timing relationship based, at least in part, on time stamps included in the control messages.