问题
Why in following pipeline I have None timestamp at beginning of reading text from .srt file with subtitles?
Its a problem for me as I want to mux it later with h264 video from other src, and that fails due to "Buffer has no PTS" from muxer.
GStreamer version 1.14.5
gst-launch-1.0 filesrc do-timestamp=true location=English.srt ! queue ! fakesink silent=false -v
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = event ******* (fakesink0:sink) E (type: stream-start (10254), GstEventStreamStart, stream-id=(string)a02d40ac74fcf80941cc61947d76a1e054212aa98d213ab8cf403f1634f3abb0, flags=(GstStreamFlags)GST_STREAM_FLAG_NONE, group-id=(uint)1;) 0x563e90b389e0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = event ******* (fakesink0:sink) E (type: segment (17934), GstEventSegment, segment=(GstSegment)"GstSegment, flags=(GstSegmentFlags)GST_SEGMENT_FLAG_NONE, rate=(double)1, applied-rate=(double)1, format=(GstFormat)GST_FORMAT_TIME, base=(guint64)0, offset=(guint64)0, start=(guint64)0, stop=(guint64)18446744073709551615, time=(guint64)0, position=(guint64)0, duration=(guint64)18446744073709551615;";) 0x563e90b38a50
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = preroll *******
Pipeline is PREROLLED ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: none, pts: none, duration: none, offset: -1, offset_end: 4095, flags: 00000040 discont , meta: none) 0x7f35f0008060
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: none, pts: none, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f0008170
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: none, pts: none, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f0008280
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: none, pts: none, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f0008390
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: 0:00:00.001037500, pts: 0:00:00.001037500, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f00084a0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: 0:00:00.001103400, pts: 0:00:00.001103400, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f00085b0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain ******* (fakesink0:sink) (4096 bytes, dts: 0:00:00.001135300, pts: 0:00:00.001135300, duration: none, offset: -1, offset_end: 4095, flags: 00000000 , meta: none) 0x7f35f00086c0
Part of file to read:
1
00:00:00,900 --> 00:00:37,690
Flesh and sin die.
2
00:00:42,530 --> 00:00:46,410
Die with Christ, that's it.
Rise with Christ.
3
00:00:46,620 --> 00:00:50,660
That's it. Holy Spirit, come.
Holy Spirit come, set her free.
4
00:00:51,120 --> 00:00:53,080
Die with Christ.
回答1:
You have absolute no logic in your pipeline. Other than the file has the extension .srt no one knows with what kind of data we deal with here. You probably want something like subparse.
gst-launch-1.0 filesrc do-timestamp=true location=English.srt ! subparse ! queue ! fakesink silent=false -v
来源：https://stackoverflow.com/questions/59361367/gstreamer-fakesink0sink-4096-bytes-dts-none-pts-none-duration-none-fo