Difference between revisions of "Using gstreamer"
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* You won't get 25 fps if autoexposure is on and local brightness not high enough: the camera will automatically lower framerate for keeping clear picture. Either lighten up, or play with image settings (notably, gain). | * You won't get 25 fps if autoexposure is on and local brightness not high enough: the camera will automatically lower framerate for keeping clear picture. Either lighten up, or play with image settings (notably, gain). | ||
| + | == Plugins == | ||
| + | * All of the plugins are listed [https://gstreamer.freedesktop.org/documentation/plugins.html here]. | ||
| + | * Alternative way of learning a plugin's parameters is: | ||
| + | <font size='2'> | ||
| + | gst-inspect-1.0 <plugin_name> | ||
| + | </font> | ||
= Command line examples = | = Command line examples = | ||
Revision as of 16:51, 9 June 2016
GStreamer is a modular node based player as well as encoder in a single application. It is possible to create chains of so called elements with a wide range of different plugins.
Contents
GStreamer
GStreamer is a library for constructing graphs of media-handling components. The applications it supports range from simple Ogg/Vorbis playback, audio/video streaming to complex audio (mixing) and video (non-linear editing) processing.
Applications can take advantage of advances in codec and filter technology transparently. Developers can add new codecs and filters by writing a simple plugin with a clean, generic interface.
Installing GStreamer
NicoLargo made a script to automatically install all the required packages for GStreamer on Ubuntu 10.04. Should work for up to (K)Ubuntu 16.04 as well.
Tips
How to get 25 FPS ?
Depends on the sensor and the exposure:
- In the sensor's datasheet find resolutions that allow the required FPS.
- You won't get 25 fps if autoexposure is on and local brightness not high enough: the camera will automatically lower framerate for keeping clear picture. Either lighten up, or play with image settings (notably, gain).
Plugins
- All of the plugins are listed here.
- Alternative way of learning a plugin's parameters is:
gst-inspect-1.0 <plugin_name>
Command line examples
Note: replace width and height accordingly to your camera setup and your computer's horsepower :P)
GStreamer 1.0 (10393 & 10353)
Display
Multipart JPEG (mjpeg), 1 channel
gst-launch-1.0 souphttpsrc is-live=true location=http://192.168.0.8:2323/mimg ! jpegdec ! xvimagesink
Notes:
- 10393 ports are 2323-2326
- 10353 port is 8081
Multipart JPEGs (mjpeg), 4 channels in 1 window
- Each source is resized to 640x480
- Text overlay and borders added
display4in1.sh:
#!/bin/sh LOC1="http://192.168.0.8:2323/mimg" LOC2="http://192.168.0.8:2324/mimg" LOC3="http://192.168.0.8:2325/mimg" LOC4="http://192.168.0.8:2326/mimg" LABEL1="CHN1" LABEL2="CHN2" LABEL3="CHN3" LABEL4="CHN4" #souphttpsrc SOUP="souphttpsrc is-live=true" #image parameters PI="image/jpeg,width=1,height=1,framerate=1000/1,pixel-aspect-ratio=1/1" #video parameters PV="videoscale ! video/x-raw,width=640,height=480" #videobox parameters PVB="videobox fill=Black top=-4 bottom=-2 left=-4 right=-2 border-alpha=0.5" #textoverlay parameters PTO="textoverlay font-desc=\"Sans 24\" shaded-background=true valignment=top halignment=left" gst-launch-1.0 -ve videomixer name=mix \ sink_0::alpha=1 sink_0::xpos=0 sink_0::ypos=0 \ sink_1::alpha=1 sink_1::xpos=646 sink_1::ypos=0 \ sink_2::alpha=1 sink_2::xpos=0 sink_2::ypos=486 \ sink_3::alpha=1 sink_3::xpos=646 sink_3::ypos=486 \ ! \ xvimagesink sync=false \ $SOUP location=$LOC1 ! $PI ! jpegdec ! $PV ! $PVB ! $PTO text=$LABEL1 ! mix. \ $SOUP location=$LOC2 ! $PI ! jpegdec ! $PV ! $PVB ! $PTO text=$LABEL2 ! mix. \ $SOUP location=$LOC3 ! $PI ! jpegdec ! $PV ! $PVB ! $PTO text=$LABEL3 ! mix. \ $SOUP location=$LOC4 ! $PI ! jpegdec ! $PV ! $PVB ! $PTO text=$LABEL4 ! mix.
Live RTSP stream
Notes:
- careful with streams at higher resolution than 1920x1088
- 10353 - works
- 10393 - doesn't have a streamer yet
native resolution
gst-launch-1.0 rtspsrc location=rtsp://192.168.0.9:554 ! rtpjpegdepay ! jpegdec ! xvimagesink sync=false
resized, 640x480
gst-launch-1.0 rtspsrc location=rtsp://192.168.0.9:554 ! rtpjpegdepay ! jpegdec ! videoscale ! video/x-raw,width=640,height=480 ! xvimagesink sync=false
GStreamer 0.10 (10353)
Display
Notes:
- Careful with streams at higher resolution than 1920x1088
Live RTSP stream
native resolution
gst-launch-0.10 rtspsrc location=rtsp://192.168.0.9:554 ! rtpjpegdepay ! jpegdec ! queue ! ffmpegcolorspace ! xvimagesink sync=false
resized, fit in window
gst-launch-0.10 rtspsrc location=rtsp://192.168.0.9:554 ! rtpjpegdepay ! jpegdec ! queue ! ffmpegcolorspace ! videoscale ! xvimagesink sync=false
Dumping
mjpeg dumping
gst-launch -v rtspsrc location=rtsp://192.168.0.9:554 ! queue ! rtpjpegdepay ! \
videorate ! capsfilter caps = "image/jpeg, framerate=(fraction)25/1, width=1024, height=768" ! \
queue ! matroskamux ! filesink location=/tmp/test.mkv
YUV Dumping
gst-launch -v rtspsrc location=rtsp://192.168.0.9:554 ! queue ! rtpjpegdepay ! queue ! jpegdec ! queue ! \
videorate ! capsfilter caps="video/x-raw-yuv, format=(fourcc)I420, width=(int)1024, height=(int)768, framerate (fraction)25/1" ! \
queue ! avimux ! filesink location=/tmp/test.avi
Dump transcoding example
gst-launch filesrc location=test.mkv ! matroskademux ! queue ! jpegdec ! queue ! theoraenc bitrate=4000 ! queue ! oggmux ! filesink location=test.ogg
Live encoding
gst-launch -v rtspsrc location=rtsp://192.168.0.9:554 ! queue ! rtpjpegdepay ! queue ! jpegdec ! queue ! \
videorate ! capsfilter caps="video/x-raw-yuv, format=(fourcc)I420, width=(int)1024, height=(int)768, framerate=(fraction)25/1" ! \
queue ! theoraenc bitrate=4000 ! queue ! oggmux ! filesink location=/tmp/test1024.ogg
Notes:
- I did some benchmarks; a Core 2 Quad Q6600 (2.4 Ghz) is not powerful enough for h264 encoding @fullHD resolution (using 4 treads).
