Video Support
This article discusses the video support that has been added to SIP Endpoint SDK. This support consists of:
- A new video control interface
- New video call control features that have been added to the existing call control interface
This article also outlines the requirements for processing High Definition video.
High Definition Video Requirements
Due to the complex processing required for High Definition video, all of the endpoints that are involved in a video conversation must run on computers that meet a certain minimum hardware performance level. As the actual CPU performance can no longer be accurately measured in MHz and since video processing performance depends on a wide variety of factors, Genesys recommends that you use the free benchmarking tool NovaBench to assess whether your hardware meets the requirements for successful HD video processing.
For 720p HD video, the minimum requirements are (in addition to what the camera manufacturer requires):
- A total NovaBench score of at least 500 (with a Graphic Test sub-score of at least 12), with recommended scores of at least 800 and 20, respectively
- 2 GB RAM
- 1 Mbps upload and download speed (for a total bandwidth of 2 Mpbs)
SIP Endpoint SDK for .NET does not currently support video resolutions higher than 720p.
Video Control
The IVideoControl interface is in the Genesyslab.Sip.Endpoint.Provider.CP namespace. It allows you to work with events and information related to:
These features are discussed in the following sections.
Video Source
This SDK provides methods to get or set video source–related information:
| Method | Description |
|---|---|
| bool HasCaptureDevice(); | Returns true if the SDK has been configured to work with a camera. |
| String^ GetCurrentCaptureDeviceName(); | Returns the names of the devices currently being used for video. |
| array<VideoDevice^>^ GetAllSystemCaptureDevices(); | Returns the names of all available cameras known to the operating system. |
| GsStatus SetCaptureDevice(int deviceId); | Picks up a capture device by its device ID and gets its status if the device has been successfully reserved. |
| VideoCapability^ GetVideoCapability(int deviceId, int N); | Returns capture device video capability by device ID and capability order number. |
| int GetNumberVideoCapabilities(int deviceId); | Returns a number of supported capabilities by device ID. |
Video Frame Events
The SDK also provides video frame–related events:
| Method | Description |
|---|---|
| event EventHandler<EndpointEventArgs^>^ VideoFrameSizeReceived; | Provides notification about video frame size. |
| event EventHandler<EndpointEventArgs^>^ VideoFrameDelivered; | Provides notification that a video frame has been received with size shown by VideoFrameSizeReceived. |
Video Call Control
SIP Endpoint SDK’s ICallControl interface, which is in the Genesyslab.Sip.Endpoint.Provider.Genesys namespace, has methods to dial and answer a session with or without video:
| Method | Description |
|---|---|
| void Dial(int connectionId, String^ destination, bool video, String^ data); | Starts dialing to place an outgoing call from the connection with ID = connectionId to destination. If video=true, the video is offered. |
| void Answer(int sessionId, bool video); | Answers an incoming call with sessionId and if video=true, the offered video is accepted. |
Access to Raw Video Frames
SIP Endpoint SDK 8.1.2 for .NET provides access to raw video frames in BGR32 format.
The following API has been added:
public enum class VideoRenderFormat {
i420 = 0,
YV12 = 1,
YUY2 = 2,
UYVY = 3,
IYUV = 4,
ARGB = 5,
RGB24 = 6,
RGB565 = 7,
ARGB4444 = 8,
ARGB1555 = 9,
MJPEG = 10,
NV12 = 11,
NV21 = 12,
BGRA = 13,
Unknown = 99
};
You can use these methods to add and remove local and remote videos:
// Start/Stop Local Video to be shown in the Windows Form with handle GsStatus StartLocalVideo(VideoCapability^ inOut, IntPtr handle, unsigned zOrder, float left, float top, float right, float bottom); GsStatus StopLocalVideo(); // Start/Stop Remote Video for sessionId to be shown in the Windows Form with handle GsStatus StartRemoteVideo(int sessionId, IntPtr handle, unsigned zOrder, float left, float top, float right, float bottom); GsStatus StopRemoteVideo(int sessionId);
The following methods may be used to add or remove the local or remote video renderer:
// Add/Remove External Local Video Renderer void AddLocalVideoRenderer(VideoRenderFormat format); void RemoveLocalVideoRenderer();
// Add/Remove External Remote Video Renderer void AddRemoteVideoRenderer(VideoRenderFormat videoFormat, int sessionId); void RemoveRemoteVideoRenderer(int sessionId);
Adding Video to an Audio-Only Call
In order to add video to an existing session, one of the supported video codecs should be specified in the SipEndpoint.config file:
<domain name="codecs">
. . .
<section name="vp8">
<setting name="payload_type" value="100"/>
</section>
<section name="h264">
<setting name="payload_type" value="108"/>
<setting name="fmtp" value="profile-level-id=420028"/>
</section>
<section name="vp9">
<setting name="payload_type" value="101"/>
</section>
</domain>If auto_accept_video is enabled and the other party adds video during an active audio call, video is automatically added to the endpoint. However, if auto_accept_video is not enabled and the other party adds video during an active audio call, then the user is prompted to either accept or reject the video.
API
The ICallControl Interface has been extended with these methods:
GsStatus SendVideoOffer(int sessionId);
GsStatus AnswerVideoOffer(int sessionId, bool accept);
GsStatus RemoveVideoStream(int sessionId);You can add video to audio-only calls using both built-in and external video frame renderers.
Application Notes
Local video should be started before you add the video. If the media offer is accepted at this point, the video becomes bidirectional. If there is a request to remove the video, the local video is disconnected from the session.
Audio-video scenarios
Video Offer Rejected By Remote Party
| Local party | Remote party | API |
|---|---|---|
| Establish audio-only session | ||
| Voice to video escalation | ||
| Start local video | ||
| Request to add video | SendVideoOffer(sessionId) | |
| Receive session status | SessionStatus.MediaOffer | |
| Reject video offer | AnswerVideoOffer(sessionId, FALSE) | |
| Receive session status | SessionStatus.MediaRejected | |
| Audio-only session established | ||
Video Offer Accepted By Remote Party
| Local party | Remote party | API |
|---|---|---|
| Add video to audio-only call | ||
| Voice to video escalation | ||
| Start local video | StartLocalVideo() | |
| Request to add video | SendVideoOffer(sessionId) | |
| Receive session status | SessionStatus.MediaOffer | |
| Accept video offer | AnswerVideoOffer(sessionId, TRUE) | |
| Receive session status | SessionStatus.MediaAccepted | |
| Show remote video | Show remote video | StartRemoteVideo(sesionId) |
| Bidirectional video session established | ||
Video Removed From The Call
| Local party | Remote party | API |
|---|---|---|
| Existing bidirectional video session | ||
| Remove video | RemoveVideoStream(sessionId) | |
| Receive session status | Receive session status | SessionStatus.MediaRejected |
| Close remote video | Close remote video | StopRemoteVideo(sesionId) |
| Voice only session | ||