Nvv4l2decoder latency varies with live-streaming and file based decoding


I am trying to measure the latency of nvv4l2decoder element with live-streaming and file based decoding.

I observed that latency of nvv4l2decoder element with live-streaming is ~4msec and observed ~48msec with file-based decoding.

Live-streaming pipeline:
GST_DEBUG=“GST_TRACER:7” GST_TRACERS=“interlatency” GST_DEBUG_FILE=udpsrc_nvv4l2decoder_nvv4l2h265enc_pl1_fakesink.log
gst-launch-1.0 udpsrc port=50000 buffer-size=2000000 caps=“application/x-rtp , media=video, clock-rate=90000, payload=96, encoding-name=H264”
! rtpjitterbuffer
! rtph264depay
! nvv4l2decoder enable-max-performance=1 disable-dpb=true
! nvv4l2h265enc preset-level=1 MeasureEncoderLatency=1 maxperf-enable=1
! fakesink

File-based pipeline:
GST_DEBUG=“GST_TRACER:7” GST_TRACERS=“interlatency” GST_DEBUG_FILE=filesrc_nvv4l2decoder_fakesink.log
gst-launch-1.0 filesrc location=AIR_1080p30_nv12.h264
! h264parse
! nvv4l2decoder enable-max-performance=1 disable-dpb=true
! fakesink

filesrc_nvv4l2decoder_fakesink.log (192.7 KB) udpsrc_nvv4l2decoder_nvv4l2h265enc_pl1_fakesink.log (6.0 MB) I have attached logs of latency details.

Could you please explain why the latency varies in case of live-streaming and file-based decoding ?


This looks to be duplicate of