Displaying a video picture in a menu with solid background

Description:

In some applications with full screen OSD it might be useful to show a small video picture within the menu, so that the user can follow the video content. This could be required e.g. in an EPG panel. This article shows how you can reach this even if the panel has a solid background color or image.

Solution:

Usually the UI objects are drawn in blend mode. This enables transparent or semi-transparent UI parts on top of other UI elements. Additionally EmWi offers to use the copy mode. In this case an UI object is copied directly to the physical graphics memory. This brings a higher performance, but it makes overlapping of transparent UI objects impossible – the menus behind would be simple overwritten by the content of the top menu.

For our case – to show a small rectangular area with video picture from the background - we use exactly this effect. We drag and drop a new rectangle from the Templates gallery "Views" in our menu, set the property "Mode" of the rectangle to "Graphics::Mode.Copy" and its color to transparent. Of course you need to set the correct position and size for the rectangle as well as for the video picture in the background, but from EmWi side the solution is very simple.

See also:

Keywords:

Picture, Video, PIP, frame, cut, rectangle, area, copy, blend, transparency, transparent