gst-freeze

A Gstreamer plugin to freeze the displayed image. Used in camera_gui application

Version 1.0

About

This plugin allows to freeze the video stream according a parameter in the gstreamer pipeline or by a manual user entry

Dependencies

The following libraries are required for this plugin.

• v4l-utils
• libv4l-dev
• libgstreamer1.0-dev
• libgstreamer-plugins-base1.0-dev
• meson

Debian based system (Jetson):

sudo apt install v4l-utils libv4l-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev meson

Note : if you are using a Yocto distribution, look at the github to find a .bbappend file which provides all packages to your distribution

Compilation

Ubuntu (Jetson)

First you must make sure that your device's clock is correctly setup. Otherwise the compilation will fail.

Using Meson

In the gst-freeze folder do:

meson build

ninja -C build

sudo ninja -C build install

Yocto (IMX)

First you must make sure that your device's clock is correctly setup. Otherwise the compilation will fail.

Using Meson

In the gst-freeze folder do:

meson build

ninja -C build install

Installation test

To test if the plugin has been correctly install, do:

export GST_PLUGIN_PATH=/usr/local/lib/gstreamer-1.0/
gst-inspect-1.0 freeze

If the plugin failed to install the following message will be displayed: "No such element or plugin 'freeze'"

Uninstall

''' sudo rm /usr/local/lib/gstreamer-1.0/libgstfreeze.* '''

Usage

By default the plugin is installed in /usr/local/lib/gstreamer-1.0. It is then required to tell gstreamer where to find it with the command:

export GST_PLUGIN_PATH=/usr/local/lib/gstreamer-1.0/

The plugin can be used in any gstreamer pipeline by adding '''freeze''', the name of the plugin.

Pipeline examples:

With fake image pipeline:

gst-launch-1.0 videotestsrc ! freeze ! videoconvert ! ximagesink

With simple video stream:

gst-launch-1.0 v4l2src ! freeze ! queue ! videoconvert ! queue ! xvimagesink sync=false

By default, the plugin listen for user inputs in the terminal. You can freeze and unfreeze the video stream by entering '''f''' in the terminal.

Plugin parameters

• freeze:

  • Type: boolean
  • Default value: false
  • Description: Freeze the stream without blocking the pipeline

• listen:

  • Type: boolean
  • Default value: true
  • Description: Listen for user inputs in the terminal