[question] gstreamer usability

[rickyjames35]

What is your question?

I'm attempting to use gstreamer https://conan.io/center/recipes/gstreamer?version=1.24.7 via Conan. I'm able to build and link just fine by listing it in my conanfile.py, adding find_package(gstreamer CONFIG REQUIRED) to my CMakeLists.txt and adding gstreamer::gstreamer to my target_link_libraries call. This builds and links exactly as expected with no problems. However when I go to run and test, it does not go as expected. Just running and testing the most basic example basic-tutorial-1.c results in a failed creation of the pipeline. However when I bypass using Connan and link gstreamer directly from my host it runs just fine. I have not started debugging yet but I'm suspicious that it has to do with the Conan recipe not working correctly. I've found this post #26963 that states "The existing GStreamer recipes on ConanCenter are quite incomplete." Can someone confirm the status of the gstreamer/1.24.7 recipe? Should I avoid using it for now?

Have you read the CONTRIBUTING guide?

• I've read the CONTRIBUTING guide

[rickyjames35]

I've figured most everything out. Hopefully this saves someone a lot of time when consuming this package...
In general you need plugins in order to actually use the majority of gstreamer. Here's an example of the plugins:

libgstreamer-plugins-base1.0-dev
libgstreamer-plugins-bad1.0-dev
gstreamer1.0-plugins-base
gstreamer1.0-plugins-good
gstreamer1.0-plugins-bad
gstreamer1.0-plugins-ugly

Install instructions for reference: https://gstreamer.freedesktop.org/documentation/installing/on-linux.html?gi-language=c
If you look at the recipe for gstreamer https://github.com/conan-io/conan-center-index/blob/master/recipes/gstreamer/all/conanfile.py you will notice it builds it as a static lib by default. However I'm guessing it's just building the base libgstreamer1.0-dev not all the plugins which are needed to actually use this library. If you follow the basic tutorial as I did using the static lib you will fail to create the pipeline https://gstreamer.freedesktop.org/documentation/tutorials/basic/hello-world.html?gi-language=c There will be a few errors in cout but it won't be too obvious that you're missing plugins. I was able to work around this by telling conan I wanted the shared version. Here is an example conanfile.py:

from conan import ConanFile

class ConanFile(ConanFile):
    settings = "os", "compiler", "build_type", "arch"
    generators = "CMakeDeps"

    def requirements(self):
        self.requires("gstreamer/1.24.7")

    def configure(self):
        self.options["gstreamer"].shared = True
        self.options["glib"].shared = True

Notice I also had to make glib shared. Now in order to run you have to install the plugins to your runtime environment in order for it to actually find them, again check out the install instructions https://gstreamer.freedesktop.org/documentation/installing/on-linux.html?gi-language=c Now you're almost there except CMake likes to hard code RPATHs by default https://cmake.org/cmake/help/latest/variable/CMAKE_SKIP_RPATH.html This will telling my executable to look in my ~/.conan2 directories for my plugins, not my system /usr/lib. set(CMAKE_SKIP_RPATH ON) fixed that issue. Now it seems to work well. I'm sure there are improvements that can be made but hopefully this helps get gstreamer working for you via conan. If you want to bypass conan then you can just apt install via the install instructions and in your CMakeList.txt use:

find_package(PkgConfig REQUIRED)
pkg_check_modules(GST REQUIRED gstreamer-1.0)

However then you don't get the advantages of conan like easily cross compiling this library for a different target architecture. Fyi I was able to get this lib working properly on a x86_64 PC and aarch64 Nvidia Jetson Orin using the conan method described here. Good luck!