GStreamer logs "Buffer has no PTS" when use omxh264enc and mp4mux in the same pipeline

Question

I am trying to encode h264 stream with omxh264enc and mux it to mp4 container with mp4mux on Lichee Pi, TH1520.

Here is the example pipeline:

gst-launch-1.0 filesrc location=test_h264.mp4 ! decodebin \
  ! rawvideoparse use-sink-caps=true \
  ! omxh264enc ! h264parse ! mp4mux ! filesink location=t_h264.mp4

But GStreamer logs such error:

ERROR: from element /GstPipeline:pipeline0/GstMP4Mux:mp4mux0: Could not multiplex stream.
Additional debug info:
../gst/isomp4/gstqtmux.c(5410): gst_qt_mux_add_buffer (): /GstPipeline:pipeline0/GstMP4Mux:mp4mux0:
Buffer has no PTS.

Changing mp4mux to qtmux logs the same error. I tired to set properties of every element in the pipeline but failed.

Answer 1

This question is silimar to gstreamer mux raw h264 to mp4?.

According to Raspberry Pi Forum and freedesktop GitLab, it seems that the requirements for qtmux on timestamp has been changed since GStreamer 1.10.x, while h264parse and qtmux didn't fulfill those requirements. h264parse has been fixed. But gst-omx is long dead and has been retired, maybe it is not profitable to modify the source code.

My solution is to use avenc_mp4 instead.

gst-launch-1.0 filesrc location=test_h264.mp4 ! decodebin \
  ! rawvideoparse use-sink-caps=true \
  ! omxh264enc ! h264parse ! avenc_mp4 ! filesink location=t_h264.mp4

But avenc is not recommended to use from GStreamer manual, and it cannot mux h265 or vp9 (matroskamux doesn't support gst-omx as well). I would be appreciated if anyone provides a better solution to fix gst-omx directly.