Choppy or There Are Brief Pauses During Playing Video in Miracast

[sandipsathvara]

Hi,

We are using the nitrogen6_max board with wl1837 module over SDIO interface. Android release is boundary-imx-kk4.4.3_2.0.0-ga . We are doing screencasting of one nitrogen6_max board to another nitrogen6_max using the miracast at 5Ghz wifi band. Miracast performance is not consistent all time, Choppy or brief Image pause happening during the screencasting.

For debugging this issue we have tried to change various encoder parameters like Bitrate, framerate, iframe interval, streaming video resolution but from that, we didn't get any performance improvement, we have also measured the p2p signal strength and wifi throughput at both ends and that seems ok.

eventually, we came to know that Choppy effect is happening, while miracast sink device requesting for the IDR Frame. 

We have also tried to ignore this IDR frame request at the miracast source side. But in that case, miracast video stuck. We are not able to identify that why sink device request for the IDR frame. We are ready with the prototype but now, we are stuck with this quality issue. Kindly help us on priority, we spent a very long time to debug this choppy video issue.

Debugging logs at source side ..

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01-02 00:06:33.950 I/PlaybackSession( 137): requestIDRFrame
01-02 00:06:34.220 I/WifiDisplaySource( 137): onReceiveClientData() session[2] method[SET_PARAMETER] 
01-02 00:06:34.220 I/WifiDisplaySource( 137): [SET_PARAMETER rtsp://localhost/wfd1.0 RTSP/1.0
01-02 00:06:34.220 I/WifiDisplaySource( 137): content-length: 17
01-02 00:06:34.220 I/WifiDisplaySource( 137): cseq: 5
01-02 00:06:34.220 I/WifiDisplaySource( 137): date: Fri, 02 Jan 1970 01:20:05 +0000
01-02 00:06:34.220 I/WifiDisplaySource( 137): session: 1295915225
01-02 00:06:34.220 I/WifiDisplaySource( 137): user-agent: stagefright/1.2 (Linux;Android 4.4.3)
01-02 00:06:34.220 I/WifiDisplaySource( 137):
01-02 00:06:34.220 I/WifiDisplaySource( 137): wfd_idr_request
01-02 00:06:34.220 I/WifiDisplaySource( 137): ] 

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[matthieuvanin]

Hi, 

The wfd-idr-request, is a miracast optional feature consisting of the sink asking to the source to send an IDR H264 frame (through a RTSP M13 message) based on some internal quality thresholds. Better to disable the support of such feature on the sink side, as the feature support is negotiated anyway at the beginning of the Miracast session (RTSP M3 message). If the sink declares not supporting it, it won't be used. 

Regards

Matthieu

[igorpadykov]

Hi Sandip

miracast is provided as part of Extended Mulimedia Feature Packages
and supported through using NXP Professional Services :

NXP Professional Services|NXP 

Software provided by third parties are supported by their support services:

Support - Boundary Devices 

Best regards
igor