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# RTP header info

A 16-bit integer specifying various values to be set in the RTP header.

## Overview

The bits of the field are defined as follows.

|Bit|Value       |
|---|------------|
|0  |reserved    |
|1  |reserved    |
|2  |P           |
|3  |X           |
|4  |reserved    |
|5  |reserved    |
|6  |reserved    |
|7  |reserved    |
|8  |M           |
|9  |payload type|
|0  |payload type|
|1  |payload type|
|2  |payload type|
|3  |payload type|
|4  |payload type|
|5  |payload type|

The RTP header information field contains the elements as follows:

|Field       |Bit#|Description                                                                                                                                                                                                                                                         |
|------------|----|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|P           |2   |A 1-bit number corresponding to the padding (P) bit in the RTP header. This bit should probably not be set, since a server that needs different packet padding would need to unpad and repad the packet itself.                                                     |
|X           |3   |A 1-bit number corresponding to the extension (X) bit in the RTP header. This bit should probably not be set, since a server that needs to send its own RTP extension would either not be able to, or would be forced to replace any extensions from the hint track.|
|M           |8   |A 1-bit number corresponding to the marker (M) bit in the RTP header.                                                                                                                                                                                               |
|Payload type|9-15|A 7-bit number corresponding to the payload type (PT) field of the RTP header.                                                                                                                                                                                      |

All undefined bits are reserved and must be set to zero. Note that the location of the defined bits are in the same bit location as in the RTP header.

---

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