Difference between revisions of "Gstreamer"

Revision as of 16:56, 11 April 2016

Installation

$ make menuconfig

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        [*] gstreamer
        [*]   require libxml2 for registry and load/save
        -*-   gst-plugins-base  --->
        [*]   gst-plugins-good  --->
        [*]   gst-plugins-bad  --->
        [*]   gst-plugins-ugly  --->

Plugins worth to activate:

• base:
• good:
• bad:
• ugly:

Usage

Check installed plugins

• To see all installed plugins:

# gst-inspect
videoscale:  videoscale: Video scaler
queue2:  queue2: Queue               
ffmpegcolorspace:  ffmpegcolorspace: FFMPEG Colorspace converter
audiorate:  audiorate: Audio rate adjuster                      
audioconvert:  audioconvert: Audio converter                    
audioresample:  audioresample: Audio resampler                  
volume:  volume: Volume
...

• To have more details about one particular plugin (here alsasrc):

# gst-inspect alsasrc
Factory Details:     
  Long name:    Audio source (ALSA)
  Class:        Source/Audio       
  Description:  Read from a sound card via ALSA
  Author(s):    Wim Taymans <wim@fluendo.com>  
  Rank:         primary (256)                  

Plugin Details:
  Name:                 alsa
  Description:          ALSA plugin library
  Filename:             /usr/lib/gstreamer-0.10/libgstalsa.so
  Version:              0.10.25                              
  License:              LGPL                                 
  Source module:        gst-plugins-base                     
  Binary package:       GStreamer Base Plug-ins source release
  Origin URL:           Unknown package origin                
...
<cut>

Audio

• play a monotic tone to check your sound configuration is working (if not please configure ALSA):

# gst-launch audiotestsrc ! audioconvert ! audioresample ! alsasink

• same test but with a given sound card (if you have more than one like on the APF6Dev):

# gst-launch audiotestsrc ! audioconvert ! audioresample ! alsasink device='sysdefault:CARD=imxhdmisoc'

• play a music file (here a .ogg, supposing the libgstogg plugin was installed):

# gst-launch filesrc location=toto.ogg ! decodebin ! audioconvert ! audioresample ! alsasink

• record a sound from an Input Line/Mic and store it as an uncompressed wav file:

# gst-launch alsasrc ! audioconvert ! audioresample ! wavenc ! filesink location=mic.wav

• record a sound from an Input Line/Mic and compress it (ogg/worbis):

# gst-launch alsasrc ! audioconvert ! audioresample ! vorbisenc ! oggmux ! filesink location=mic.ogg

• record a sound from an Input Line/Mic @ 8KHz (16KHz is too CPU consuming on APF27), compress it with Speex and send it to your Host (here 192.168.1.2) at port 6666:

# gst-launch -v alsasrc ! audioconvert ! audioresample ! 'audio/x-raw-int,rate=8000,width=16,channels=1' ! speexenc ! rtpspeexpay ! udpsink host=192.168.1.2 port=6666

• to live decode the stream on your PC:

$ gst-launch udpsrc port=6666 caps="application/x-rtp, media=(string)audio, clock-rate=(int)16000, encoding-name=(string)SPEEX, encoding-params=(string)1, payload=(int)110" ! gstrtpjitterbuffer ! rtpspeexdepay ! speexdec ! audioconvert ! audioresample ! autoaudiosink

• to store the stream in Wav format on your PC:

$ gst-launch udpsrc port=6666 caps="application/x-rtp, media=(string)audio, clock-rate=(int)16000, encoding-name=(string)SPEEX, encoding-params=(string)1, payload=(int)110" ! gstrtpjitterbuffer ! rtpspeexdepay ! speexdec ! audioconvert ! audioresample ! wavenc ! filesink location=toto.wav

Video

Plugins

• You'll need to activate a few plugins in Buildroot menuconfig to play videos with Gstreamer:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        -*-   gst-plugins-base  --->
              [*]   ffmpegcolorspace (mandatory for video playback)
              ...
              [*]   playback (mandatory)
        [*]   gst-plugins-good  --->
              [*]   videobox
              [*]   videocrop
        [*]   gst-plugins-bad  --->
              [*]   fbdev

Test installation

• To test your Gstreamer installation, you need to select a plugin in Buildroot menuconfig:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        -*-   gst-plugins-base  --->
              [*]   videotestsrc

• Then on your APF system, launch the following command:

# gst-launch -v videotestsrc ! videocrop top=42 left=1 right=4 bottom=0 ! fbdevsink

You must see a pattern displayed on the screen if your Gstreamer installation is working well.

Play video

MPEG 1/2

• If you want to play MPEG 1/2 video, you have to install some plugins in Buildroot menuconfig:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        [*]   gst-plugins-bad  --->
              [*]   mpegdemux
              [*]   mpegtsmux
              [*]   mpeg4videoparse
              [*]   mpegvideoparse
        [*]   gst-plugins-ugly  --->
              [*]   mpegaudioparse
              [*]   mpegstream

With FFmpeg decoder

• In Buildroot menuconfig, select:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        -*- ffmpeg  --->
        ...
        [*] gst-ffmpeg

• On your APF system, play the video with the command:

# gst-launch filesrc location=VIDEO_FILE_LOCATION ! mpegdemux ! ffdec_mpegvideo ! ffmpegcolorspace ! fbdevsink

With mpeg2dec decoder

• In Buildroot menuconfig, select:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        [*]   gst-plugins-ugly  --->
              [*]   mpeg2dec

• On your APF system, play the video with the command:

# gst-launch filesrc location=VIDEO_FILE_LOCATION ! mpegdemux ! mpeg2dec ! ffmpegcolorspace ! fbdevsink

Take photos

• You will need some more plugins:

Package Selection for the target  --->
    Audio and video libraries and applications  --->
        ...
        [*]   gst-plugins-good  --->
              [*]   jpeg (JPEG support)
              [*]   png (PNG support)

# gst-launch v4l2src ! video/x-raw-rgb,width=1024,height=768 ! ffmpegcolorspace ! pngenc ! filesink location=/root/photo.png

APF6 with Freescale kernel

On the APF6 with legacy Freescale kernel (apf6legacy_defconfig), you can use hardware H.264 VPU to decode/encode videos without using CPU.

• First get some video for test ;-)

# cd /usr/share/
# wget http://download.blender.org/peach/bigbuckbunny_movies/big_buck_bunny_480p_h264.mov

• Play the H.264 video with hardware decoding and framebuffer rendering:

# gst-launch filesrc location=/usr/share/big_buck_bunny_480p_h264.mov ! qtdemux ! vpudec ! mfw_v4lsink

• Same with audio:

# gst-launch filesrc location=/usr/share/big_buck_bunny_480p_h264.mov ! qtdemux name=demux \
    demux. ! queue max-size-buffers=0 max-size-time=0 ! vpudec ! mfw_v4lsink \
    demux. ! queue max-size-buffers=0 max-size-time=0 ! decodebin ! audioconvert ! audioresample ! alsasink

Links

• http://www.gstreamer.net/
• http://lists.affinix.com/pipermail/delta-affinix.com/2009-April/001493.html