Audio (sound) has to be enabled on your track (ie: video) for you to be able to hear anything when you play your preview or download your video. When I first installed openshot I had the same problem as the OP- enabling audio solved it.
Tryed Edit-Preferences,(Tab) Preview, Playback Audio Device (changed to DirectSound;Speakers. This did not work but did work if I chose speakers on attached monitor. When leaving as default or selecting DirectSound Speakers nothing else would play through those speakers when openshot was active. Its like open shot has had a go at using internal speakers and in process locks out other apps access.
There is still a bug with animated titles background color. When choosing (Fly Towards Camera), the background should be black by default, but it is white and no way to change it. I have used Alpha 1.4.1 in AV Linux and there's no issue, but all other distros have this bug. This has ruined my openshot creativity & experience. Also, I noticed when choosing (Dissolve) I get an error message stating that Blender is not pointing to the executable blender. blender is listed in preferences as the executable. Why has this background issue has not been fixed? Thanks.
If the computer has multiple graphics cards installed, you can choose which should be used by libopenshot. Also, you can optionally use one card for decoding and the other for encoding (if both cards support acceleration). This is currently only supported on Linux, due to the device name FFmpeg expects (i.e. **/dev/dri/render128**). Contributions welcome if anyone can determine what string format to pass for Windows and Mac.
FFmpeg 4 + nVidia The manual at: _nvidia_encode works pretty well. We could compile and install a version of FFmpeg 4.1.3 on Mint 19.1 that supports the GPU on nVidia cards. A version of openshot with hardware support using these libraries could use the nVidia GPU.
OpenShot is written in Python, PyQt5, C++ and offers a Python API.[12] OpenShot's core video editing functionality is implemented in a C++ library, libopenshot. The core audio editing is based on the JUCE library.
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