4

I am trying to run certain pipelines on the Command prompt for playing a video and I am often getting these errors/messages/warnings :

WARNING: erroneous pipeline: no element "qtdemux"
WARNING: erroneous pipeline: no element "playbin2"
WARNING: erroneous pipeline: no element "decodebin2"
ERROR: pipeline could not be constructed: no element "playbin".

Following are the pipelines : 

gst-launch filesrc location=path to the mp4 file ! playbin2 ! queue ! ffmpegcolorspace ! autovideosink

or 

gst-launch -v filesrc location=path to the mp4 file ! qtdemux name=demuxer ! { queue ! decodebin ! sdlvideosink } { demuxer. ! queue ! decodebin ! alsasink }

or 

gst-launch -v playbin uri=path to the mp4 file

or 

gst-launch -v playbin2 uri=path to the mp4 file

Questions

  1. I wanted to know, if I am I missing the plugins to execute this.
  2. How do I know which plugin is responsible for which or found where?
  3. What is the benefit of implementing the pipeline via c code.Are the missing plugins still required.
  4. Is it good to install the missing plugins form the Synaptic manager or form the Gstreamer site(base,good,bad,ugly)

  5. When we do gst-inspect we get output like this:

    postproc:  postproc_hdeblock: LibPostProc hdeblock filter
libvisual:  libvisual_oinksie: libvisual oinksie plugin plugin v.0.1
flump3dec:  flump3dec: Fluendo MP3 Decoder (liboil build)
vorbis:  vorbistag: VorbisTag
vorbis:  vorbisparse: VorbisParse
vorbis:  vorbisdec: Vorbis audio decoder
vorbis:  vorbisenc: Vorbis audio encoder
coreindexers:  fileindex: A index that stores entries in file
coreindexers:  memindex: A index that stores entries in memory
amrnb:  amrnbenc: AMR-NB audio encoder
amrnb:  amrnbdec: AMR-NB audio decoder
audioresample:  audioresample: Audio resampler
flv:  flvmux: FLV muxer
flv:  flvdemux: FLV Demuxer

What does the x : y ( x and y mean ) ?

DanMan
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Raulp
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2 Answers2

2

Answers,

It looks like gstreamer at your ends was not installed correctly. playbin2, decodebin2 are basic and part of the base plugins

1 Yes you may be missing some plugins

2 Use gst-inspect command to check if it is available

3 From C code you can manage states, register callback, learn more Yes missing plugins are still required

4 I guess gstreamer site would be better

5 Not sure about this one, would help if you arrange the result in a proper way

user2618142
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1

Most probably the GST_PLUGIN_PATH is incorrect. Please set the correct path to where the gstremer has been installed.

blganesh101
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