QML Components for Video Decoding and Rendering POC Code Available
As requested I shared the sources of the demo videos I posted recently. I tested these components with a few videos and I saw that it seems to work “reasonably well” also for 1080p h264 high profile with 5.1 audio. The current implementation uses a player class which decodes data and a surface class that renders. Rendering the video on more surfaces seems to work.
Beware that the code is not complete, it is only a proof of concept of how to implement. If you need to use it in production code, you’ll have to work pretty much on it. There are many TODO’s left and no testing has been run on the classes. The cleanup code must be completely rewritten and only pause/resume/stop commands are implemented at the moment. Also consider going through the relevant code for leaks, I didn’t pay much attention when implementing because it was my idea to refactor, sorry.
Only 1080p resolution is currently supported, never even tried anything different, you’ll probably have to look around and see where I hardcoded those values (I was in a hurry :-))
There are many unused classes in the code, I left those there only because those might be useful for new implementations.
I started to work on other things recently, so I really have few time to work on this. But still I see that many are interested, so I decided that incomplete code is better than no code. Also, I have to say I have no practical need of these components, I only worked on this as a challenge in my spare time. Now that there is no challenge anymore, I have to say I lost some interest and I’m looking for a new one 😀
This is the github URL of the repo (PiOmxTextures is the project directory): https://github.com/carlonluca/pi.
The current implementation of the OMX_MediaProcessor class uses the components implemented in the omxplayer code, with modifications to some of those. Those modified sources are placed in the omxplayer_lib directory in the project sources: I chose this architecture to make it relatively simple to merge the changes from the omxplayer sources.
How to build
To build the project, you’ll need a build of the Qt libraries, version 5.0.0 at least. Instructions on how to build can be found around the web. I also wrote a quick article on that if you need it (this is the updated version for 5.0.1).
Once you have your Qt build and Qt Creator setup, you can open the .pro file. You should also have the Raspberry sysroot somewhere in your system, and that should be known by Qt Creator. The project is based on the same dependencies of omxplayer, so you need those as well. I tested this only against a specific build of ffmpeg, which is the one omxplayer was using when I last merged: to compile you can use this script, which is included in the source tree. Just running it passing the number of compilation thread to use should be sufficient:
git clone https://github.com/carlonluca/pi cd pi/PiOmxTextures/tools ./compile_ffmpeg.sh n cd ../../ mkdir PiOmxTextures-build-rasp-release cd PiOmxTextures-build-rasp-release path_to_qmake/qmake "DEFINES+=CONFIG_APP" ../PiOmxTextures make -jn
Pay attention that the sample application renders a file whose path is hardcoded in the qml file. Change that if you want to test the sample code.
As said, this is just a proof of concept and I do not have much time to maintain it. If you want to help to fix the code and to merge new changes, issue a merge request!
Hope this code might be of help for other open source project! Feel free to leave a comment if you have any! Bye!