PHYTEC Messtechnik GmbH
© PHYTEC Messtechnik GmbH 2015
9 / 10
Support Hotline Europe:: +49 (6131) 9221-31 •
http://www.phytec.de
Support Hotline North America: 1-800-278-9913 •
http://www.phytec.com
5
GStreamer function
After login, change into the directory: \gstreamer_examples\..
cd gstreamer_examples <ENTER>.
Now you can start working with the GStreamer demo-scripts.
Information’s about the GStreamer examples are in the notes in the scripts and can be found in the phyCAM-Manual L-748.
6
GStreamer function for improved Tearing reduction
Tearing is a visual artifact in video display where the display image shows information from two or more frames in a single screen draw.
It appears as a horizontal border or line. The image part beyond the line seems to be shifted horizontally when the image content or the camera is moved.
The tearing line(s) usually move(s) vertically across the image.
The artifact occurs when the camera framerate differs from the display frame or the camera readout cycle is not in sync with the display's refresh.
Definition and background information about the tearing effect can be found in
http://en.wikipedia.org/wiki/Screen_tearing
.
The Freescale i.MX-6 processor contains an anti-tearing mechanism in the IPU unit, which can reduce the tearing effect.
However, since - depending on camera settings and camera model - the frame rate might be very different from the display’s refresh rate, tearing effects might still
be visible even if the anti-tearing mechanism is active. For applications that are intended to display live camera images on the display, additional measures should
be considered to obtain a perfect image quality. This measures can include frame rate control (trimming the camera frame rate to the display’s refresh rate), multi-
buffering of the camera image etc.
We recommend to activate the anti-tearing mechanism of the i.MX-6 when live camera images are shown on the display. For evaluation purposes with the
development kits, Phytec added GStreamer examples, that use a different fbsink – function, that activates the anti-tearing mechanism.
6.1 GStreamer function for improved Tearing reduction (Linux PD16.1.0)
From PD16.1.0 up to PD17.1.1 the GStreamer contains the "
imxpxpvideosink use-vsync=tru" plugin.
This plugin reduce the tearing. Most of the Phytec GStreamer example scripts use this plugin. Please show the scripts in path ../gstreamer_examples/.. .
For more information to "imxpxpvideosink" parameters type:
- gst-inspect-1.0 imxpxpvideosink