what's Gstreamer

First of Let me Ask do you know what’s FFmpeg ?
if your answer is yes
Now you know what’s Gstreamer; because of many works is like FFmpeg but when you need to work with Qt to show Output Video in QML we must use Gstreamer and use plugin qmlgsink

if your answer is No
Gstreamer is a software Cross Platform with many plugins for working with multimedia like sound or video to convert or do many works.

why we must use Gstreamer

I saying Gstreamer has many plugins because of those, we must do much work like can use Hardware to convert a video format to another format using GPU because GPU is very faster than CPU and resource is very low.

ok now let's go to know better than Gstreamer

Gstreamer Collections

Gstreamer plugins convert into Four Collections:

gst-plugins-base
gst-plugins-good
gst-plugins-bad
gst-plugins-ugly

gst-plugins-base

a small and fixed set of plug-ins, covering a wide range of possible types of elements; these are continuously kept up-to-date with any core changes during the development series.

gst-plugins-good

a set of plug-ins that we consider to have good quality code, correct functionality, and our preferred license (LGPL for the plug-in code, LGPL or LGPL-compatible for the supporting library).

gst-plugins-ugly

a set of plug-ins that have good quality and correct functionality, but distributing them might pose problems. The license on either the plug-ins or the supporting libraries might not be how we’d like. The code might be widely known to present patent problems.

gst-plugins-bad

a set of plug-ins that aren’t up to par compared to the rest. They might be close to being good quality, but they’re missing something - be it a good code review, some documentation, a set of tests, a real live maintainer, or some actual wide use. If the blanks are filled in they might be upgraded to become part of either gst-plugins-good or gst-plugins-ugly, depending on the other factors.

for more information

it’s was just an introduction I trying to show examples of code and show better examples for work with Gstreamer in Qt or just terminal. thank you for reading this post
have a good time.