ipm_StartMedia( )

---

Termination Events | Cautions | Errors | Example | See Also

Name:	int ipm_StartMedia(nDeviceHandle, *pMediaInfo, eDirection, usMode)
Inputs:	int nDeviceHandle	IP Media device handle
	IPM_MEDIA_INFO *pMediaInfo	pointer to media information structure
	eIPM_DATA_DIRECTION eDirection	data flow direction
	unsigned short usMode	async or sync mode setting
Returns:	0 on success -1 on failure
Includes:	srllib.h ipmlib.h
Category:	Media Session
Mode:	asynchronous or synchronous
Platform:	DM/IP, IPT, HMP

Description

The ipm_StartMedia( ) function sets media properties and starts the session. This function allows the application to set the remote and local connectivity selections. ipm_StartMedia( ) also starts RTP streaming. The remote RTP/ RTCP port information and coder information is provided in the IPM_MEDIA_INFO structure.

Parameter	Description
nDeviceHandle	handle of the IP Media device
pMediaInfo	pointer to structure; see IPM_MEDIA_INFO for details. Applications can define the following: local transmit coder and remote transmit coder local and remote RTP/RTCP protocol local and remote IP address
eDirection	media operation enumeration The eIPM_DATA_DIRECTION data type is an enumeration which defines the following values: DATA_IP_RECEIVEONLY receives data from the IP network but no data is sent. DATA_IP_SENDONLY sends data to the IP network but no data is received. DATA_IP_TDM_BIDIRECTIONAL full duplex data path (streaming media) between IP network and TDM. Used for gateway functionality. DATA_MULTICAST_SERVER multicast server mode DATA_MULTICAST_CLIENT multicast client mode
usMode	operation mode. Set to EV_ASYNC for asynchronous execution or to EV_SYNC for synchronous execution.

Termination Events

IPMEV_START_MEDIA

indicates successful completion, that is, media information was set and the session has been started. Use SRL functions to retrieve IPM_MEDIA_INFO structure fields.

IPMEV_ERROR

indicates the function failed.

Cautions

The application must wait until this function completes before calling ipm_Listen( ).

Errors

If the function returns -1 to indicate failure, call ATDV_LASTERR( ) and ATDV_ERRMSGP( ) to return one of the following errors:

EIPM_BADPARM

Invalid parameter

EIPM_BUSY

Channel is busy

EIPM_INTERNAL

Internal error

EIPM_INV_MODE

Invalid mode

EIPM_INV_STATE

Invalid state. Initial command did not complete before another function call was made.

EIPM_SYSTEM

System error

Example

#include <stdio.h>
#include <string>
#include <srllib.h>
#include <ipmlib.h> 
typedef long int(*HDLR)(unsigned long);
void CheckEvent(); 
void main()
{
    int nDeviceHandle;
    // Register event handler function with srl
    sr_enbhdlr( EV_ANYDEV ,EV_ANYEVT ,(HDLR)CheckEvent);
    /*
    .
    .
    Main Processing
    .
    .
    .
    */
    /*
    Set the media properties for a remote party using IP device handle, nDeviceHandle.
    ASSUMPTION: A valid nDeviceHandle was obtained from prior call to ipm_Open().
    */
    IPM_MEDIA_INFO MediaInfo;
    MediaInfo.unCount = 4;
    MediaInfo.MediaData[0].eMediaType = MEDIATYPE_REMOTE_RTP_INFO;
    MediaInfo.MediaData[0].mediaInfo.PortInfo.unPortId = 2328;
    strcpy(MediaInfo.MediaData[0].mediaInfo.PortInfo.cIPAddress,"111.21.0.9\n");
    MediaInfo.MediaData[1].eMediaType = MEDIATYPE_REMOTE_RTCP_INFO;
    MediaInfo.MediaData[1].mediaInfo.PortInfo.unPortId = 2329;
    strcpy(MediaInfo.MediaData[1].mediaInfo.PortInfo.cIPAddress,"111.41.0.9\n");
    MediaInfo.MediaData[2].eMediaType = MEDIATYPE_REMOTE_CODER_INFO;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.eCoderType = CODER_TYPE_G711ULAW64K;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.eFrameSize = (eIPM_CODER_FRAMESIZE) 30;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.unFramesPerPkt = 1;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.eVadEnable = CODER_VAD_DISABLE;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.unCoderPayloadType = 0;
    MediaInfo.MediaData[2].mediaInfo.CoderInfo.unRedPayloadType = 0;
    MediaInfo.MediaData[3].eMediaType = MEDIATYPE_LOCAL_CODER_INFO;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.eCoderType = CODER_TYPE_G711ULAW64K;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.eFrameSize = (eIPM_CODER_FRAMESIZE) 30;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.unFramesPerPkt = 1;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.eVadEnable =CODER_VAD_DISABLE;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.unCoderPayloadType = 0;
    MediaInfo.MediaData[3].mediaInfo.CoderInfo.unRedPayloadType = 0;
    if(ipm_StartMedia(nDeviceHandle, &MediaInfo,DATA_IP_TDM_BIDIRECTIONAL, EV_ASYNC) == -1)
    {
        printf("ipm_StartMediaInfo failed for device name = %s with error = %d\n",
            ATDV_NAMEP(nDeviceHandle), ATDV_LASTERR(nDeviceHandle));
            /*
            .
            .
            Perform Error Processing
            .
            .
        */
    }
    /*
    .
    . Continue processing
    .
    */
} 
void CheckEvent()
{
    int nDeviceID = sr_getevtdev();
    int nEventType = sr_getevttype();
    switch(nEventType)
    {
    /*
    .
    .
    . Other events
    .
    .
        */
        /* Expected reply to ipm_StartMedia */
    case IPMEV_STARTMEDIA:
        printf("Received IPMEV_START_MEDIA for device = %s\n",
            ATDV_NAMEP(nDeviceID));
        break;
    default:
        printf("Received unknown event = %d for device = %s\n",
            nEventType, ATDV_NAMEP(nDeviceID));
        break;
    }
} 

See Also

• ipm_GetLocalMediaInfo( )
• ipm_Stop( )

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