如何将python中的async = false添加到Gstreamer splitmuxsink元素音频/视频/ H264组合

Question

Gstreamer 1.8.2 installed on an embedded device using a C920. Debian linux. I have a nice Gstreamer pipeline that uses the new splitmuxsink and almost works. I do have splitmuxsink working on a 'basic pipeline' nicely.

The first pipeline works and writes one long file mp4, audio and video and at the same time passes a preview jpeg stream to a separately handled appsink which works. Hope this is useful in any case for someone.

    self.pipeline=Gst.parse_launch('uvch264src auto-start=true iframe-period=1000 name=src1 src1.vfsrc ! queue  ! appsink drop=true name=asink max-buffers=2 emit-signals=true sync=false src1.vidsrc ! video/x-h264,width=1280,height=720,framerate=30/1,stream-format=byte-stream ! queue ! h264parse ! muxout.video_0   alsasrc do-timestamp=true device="plughw:CARD=C920,DEV=0" ! audio/x-raw,format=S16LE,rate=32000,depth=16,channels=1 ! queue ! voaacenc ! queue ! aacparse ! muxout.audio_0 mp4mux name=muxout ! filesink sync=false location=%s' % location1)

But when I convert the filesink to a 'splitmuxsink', it only creates previews, and does not start the file recording side of the stream. I do not know how (programmatically in Python) to set the attributes of splitmuxsink to replicate the sync=false that I am doing on the filesink plugin. Do I attach to a pad on splitmuxsink, or somehow setup the sink=xxx label and get_static_pad or element to then adjust the properties of that 'child' element? I believe this problem is what is causing the file splitting part of the pipeline to fail. I am looking for something like: How to resume playing after paused using gstreamer? based on this answer: gstreamer pipeline with VADER element stalls on PAUSE when used with a tee

Pipeline v2 (runs the appsink side, but splitmuxsink stays paused)

    self.pipeline=Gst.parse_launch('uvch264src auto-start=true async-handling=false message-forward=true iframe-period=1000 name=src1 src1.vfsrc ! queue  ! appsink drop=true name=asink max-buffers=200 emit-signals=true sync=true src1.vidsrc ! video/x-h264,width=1280,height=720,framerate=30/1,stream-format=byte-stream ! queue  ! h264parse ! queue ! splitmuxsink max-size-time=20000000000 max-size-bytes=5000000 name=muxout location=video2%05d.mp4  alsasrc do-timestamp=true device="plughw:CARD=C920,DEV=0" ! audio/x-raw,forma=S16LE,rate=32000,depth=16,channels=1 ! queue ! voaacenc ! queue ! aacparse ! muxout.audio_0 

As you can see, pipeline v2 has no explicit reference to sync=false as splitmuxsink does not have that property. And so that side does not start after PAUSED.

I am sure this is just going to be a tiny adjustment to create the right label and set its attributes after my

    self.muxp = self.pipeline.get_by_name('muxout')

to set the child element to async false, but I just can't see it - the muxout element (my label for splitmuxsink) does not have an async property.

Answer 1

After correspondence with development team, I was told there was a bug in split muxsink which the developer corrected in 1.8.3. An update to 1.8.3 solved the issue.

Answer 2

I think that one of the problems can be the format of SINK pad of mp4mux. splitmuxsink consists of mp4mux and filesink in the default configuration. In your pipeline you produce H264 with stream-format=byte-stream parameter, however, mp4mux expects only stream-format=avc .