Video player for QML component, using VLC as decoder. Overview. The pipeline of video playing is 1. the VLC parsing the input video(local file or rtsp stream), 2. decode it and output frame 3. convert them from YUV to RGB 4. upload to texture 5. displaying it. Note: 1. main rendering thread ini VLC engine 2. load media, created media player, set callbacks 3. video format info determine colorspace call to render thread. -> setupsFormat return number of plane. 4. lock callback Lock Buffer Mutex(I won't mess up with the frame that displaying) send pixel buffer into VLC, 5. unlock for video memory -> updateTexture 6. display callback -> paintFrame. -> update to repaint QMetaObject::invokeMethod for cross thread function call. 7. when VLC thread is ready on next frame, it call lock-> unlock-> display callback in order. Texture Mode: Synchronous Transfers GPU -------------draw BUS -------upload CPU -- copy----------copy PBO mode: Async transfer save one more memory copy, vlc will draw into pixelbuffer memory space. GPU -----------------draw0---draw1 BUS ---------upload0-upload1-upload0 CPU -- copy0-copy1---copy2 use shader to convert colorspace of texture?