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Problems when seeking on filesrc with TS file

I have generated the following test files:

gst-launch-1.0 videotestsrc is-live=true pattern=ball num-buffers=300 ! video/x-raw,framerate=30/1,format=NV12 ! timeoverlay ! x264enc key-int-max=30 speed-preset=1 tune=zerolatency ! video/x-h264,profile=high ! mpegtsmux ! filesink location=test.ts -v -e
gst-launch-1.0 videotestsrc is-live=true pattern=ball num-buffers=300 ! video/x-raw,framerate=30/1,format=NV12 ! timeoverlay ! filesink location=test.raw -v

And then they are played in a python app using parse_launch:

"filesrc name=replay location=test.ts ! queue ! tsparse ! tsdemux ! h264parse ! avdec_h264 ! videoconvert ! ximagesink sync=1 "
"filesrc name=replay location=test.raw ! videoparse format=nv12 width=320 height=240 framerate=30/1 ! videoconvert ! ximagesink sync=1 "

I have however issues when trying to do seek operations in the H264 stream (with TS container).

Without the queue after the filesrc I get:

(gst_ctrl.py:183848): GStreamer-CRITICAL **: 11:08:08.431: pushing on pad replay:src but it was not activated in push mode
0:00:08.281698886 183848 0x7f21940098c0 WARN                 basesrc gstbasesrc.c:3127:gst_base_src_loop:<replay> error: Internal data stream error.
0:00:08.281735348 183848 0x7f21940098c0 WARN                 basesrc gstbasesrc.c:3127:gst_base_src_loop:<replay> error: streaming stopped, reason error (-5)

With the queue I'm able to do a single seek operation with:

        self.pipeline.seek(1.0, Gst.Format.TIME,
             (Gst.SeekFlags.FLUSH | Gst.SeekFlags.ACCURATE),
             Gst.SeekType.SET, 0 , Gst.SeekType.NONE, -1)

But subsequent calls to seek give me:

0:00:10.778992854 183974 0x7f5e1c35d960 WARN                 tsdemux tsdemux.c:917:gst_ts_demux_do_seek: Couldn't convert start position to an offset
0:00:10.779094440 183974 0x7f5e1c35d960 WARN              mpegtsbase mpegtsbase.c:1721:mpegts_base_handle_seek_event: seeking failed error
0:00:10.779115381 183974 0x7f5e1c35d960 WARN                 tsdemux tsdemux.c:974:gst_ts_demux_srcpad_event: seeking failed
0:00:10.779150565 183974 0x7f5e1c35d960 WARN                 tsdemux tsdemux.c:974:gst_ts_demux_srcpad_event: seeking failed

I have no issues with seeking on the raw stream.

Lastly, if I change the filesrc into multifilesrc I can perform multiple seeks in the H264 encoded file. But It jumps to weird positions in the file instead of going to the start.

I have tried using Gst.SeekFlags.KEY_UNIT instead of Gst.SeekFlags.ACCURATE and trying seeking in BYTES instead of TIME, but seen no real difference...

See http://gstreamer-devel.966125.n4.nabble.com/seek-on-filesrc-with-TS-file-td4697440.html