XGameStreamingGetStreamAddedLatency

Article
06/19/2024

Gets the recent average of the streaming related latency.

Syntax

HRESULT XGameStreamingGetStreamAddedLatency(  
         XGameStreamingClientId client,  
         uint32_t* averageInputLatencyUs,  
         uint32_t* averageOutputLatencyUs,  
         uint32_t* standardDeviationUs  
)

Parameters

client _In_
Type: XGameStreamingClientId

The streaming client device that latency is being queried for.

averageInputLatencyUs _Out_
Type: uint32_t*

The average latency, in microseconds, over a recent period of time for input to be received by the Xbox game.

averageOutputLatencyUs _Out_
Type: uint32_t*

The average latency, in microseconds, over a recent period of time for a game frame to be rendered on the client device.

standardDeviationUs _Out_
Type: uint32_t*

Observed average of the measured standard deviation of jitter, in microseconds, over a recent period of time in the latency.

Return value

Type: HRESULT

Returns S_OK if successful; otherwise, returns an error code.

Potential Errors

Error Code	Error Value	Reason for Error
E_GAMESTREAMING_NOT_INITIALIZED	0x89245400	The XGameStreaming runtime has not been initialized. Call XGameStreamingInitialize before calling other APIs.
E_GAMESTREAMING_NO_DATA	0x89245402	The requested data is not available. The data may be available later.

For a list of error codes, see Error Codes.

Remarks

Note

This function isn't safe to call on a time-sensitive thread. For more information, see Time-sensitive threads.

Note

As explained below, the input and output latency values measure different values and may be calculated from different sources. These values are not expected to be similar and should be treated independently.

XGameStreamingGetStreamAddedLatency provides data about the measured latency due to the streaming of the game. This can be utilized by games to better understand the experience that the player is having with the streamed experience.

It is important to note that this does not provide the full end to end latency that a player may notice (e.g., it does not map directly to a button press on a controller attached to the streaming client device until a new frame is rendered that takes that into account.) For example, the following components are not included in these measurements:

Game engine render time
Time from when passed to render on the client device to when the player sees the image
Bluetooth® transport and decode time from the controller on the client device

Instead, the input latency includes:

The time it takes for the game streaming application to process inputs received from a controller.
Transmission time from the game streaming application over the network to the server which is running the game.

Output latency includes:

Encoding time for each frame that is rendered by the title.
Time to transmit this frame across the network to the application the player is interacting with.
Decoding time in the application, as it prepares to present the frame to the player.

XGameStreamingGetStreamAddedLatency is an average measurement which is updated every few seconds. For more precise measurements, the XGameStreamingGetAssociatedFrame API may be used. See Game streaming latency compensation deep dive for more information.

Requirements

Header: xgamestreaming.h

Library: xgameruntime.lib

Supported platforms: Windows, Xbox One family consoles and Xbox Series consoles

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