# Setting the video transmit RTP payload ID

Set the transmit payload ID for a video RTP endpoint to something other than the default value. The default payload ID values are:

- 100 (MPEG-4)

- 34 (H.263 using RFC 2190)

- 101 (H.263 using RFC 2429)

- 104 (H.264)

To set the transmit payload ID, create the MSP_CMD_RTPFDX_SET_VID_TX_PID command, and send it to the CG board.

The MSP_CMD_RTPFDX_ SET_VID_TX_PID command uses the msp_ENDPOINT_RTPFDX_ SET_VID_TX_PID structure to set the payload ID.

Note: This feature is for all video full-duplex and simplex send RTP endpoints. The procedure and example are shown for full-duplex endpoints.

For more information, see Creating and sending MSPP commands and msp_ENDPOINT_RTPFDX_SET_VID_TX_PID.

The following event can be returned:

Event | Description
MSPEVN_SENDCOMMAND_DONE | MSP_CMD_RTPFDX_SET_VID_TX_PID command was successfully sent to the specified RTP endpoint on the CG board.

#### Example

The following example shows how to set the transmit payload ID for an RTP endpoint with the MSP handle ephd:

msp_ENDPOINT_RTPFDX_SET_VID_TX_PID pidCmd;
pidCmd.txPayloadId= H2NMS_DWORD(111) ;
ret = mspSendCommand(ephd, mspBuildCommand(MSP_ENDPOINT_RTPFDX_VIDEO_H263,
MSP_CMD_RTPFDX_SET_VID_TX_PID), &pidCmd, sizeof(pidCmd));
if (ret != SUCCESS)
printf("\n\t ERROR: mspSendCommand returned failure.\n");
expectedEvent = (MSPEVN_SENDCOMMAND_DONE | MSP_CMD_RTPFDX_SET_VID_TX_PID);
if (WaitForSpecificEvent(gw, ctaQueueHd, expectedEvent, &event) != 0)
printf("\n\tERROR: mspSendCommand failed to send valid completion event\n");