GrabStrategy_LatestImageOnly - low latency capture

[FabienDanieau]

Hi,

I'm interested in achieving the lowest possible latency for streaming video using the pylonsrc element. Specifically, I'd like to know if the GrabStrategy_LatestImageOnly option is available.

My goal is to set up a pipeline similar to the following:

gst-launch-1.0 pylonsrc ! "video/x-bayer,width=2448,height=2048,framerate=60/1,format=rggb" ! queue ! bayer2rgb ! vaapipostproc ! "video/x-raw(memory:VASurface),format=NV12,width=1920,height=1606" ! vaapih264enc bitrate=4000 ! video/x-h264, profile=constrained-baseline ! webrtcsink

Additionally, I'm wondering if there are any buffer configurations available for the pylonsrc element, such as stream::MaxNumBuffer=10, that can help optimize the streaming performance.

Thanks!

[thiesmoeller]

gst-plugin-pylon/ext/pylon/gstpylon.cpp

Line 426 in 625d3bb

self->camera->StartGrabbing(Pylon::GrabStrategy_LatestImageOnly,

It is the default, like with v4l2 sources
Maximum buffers just controls how many buffers will cycle between pylon and the bayer2rgb plugin ( the first sink for the camera buffers )

[thiesmoeller]

And add vaapih264enc property tune=zerolatency....

[FabienDanieau]

It is the default, like with v4l2 sources
Maximum buffers just controls how many buffers will cycle between pylon and the bayer2rgb plugin ( the first sink for the camera buffers )

Ok got it thanks.

And add vaapih264enc property tune=zerolatency....

This option is not available for vaapih264enc unfortunately. It exists for x264enc but this encoder is too slow.

I'm not sure that the bayer2rgb is optimal in my case though. It would be better to have this conversion done by vaapipostproc I guess.