Gets a sample from the pipeline of the currently displayed image in preview, in the specified format.
Note that if you use "ANY" caps for caps
, then the current format of the image is used. You can retrieve these caps from the
returned sample with get_caps.
this |
A Pipeline in PLAYING or PAUSED |
caps |
Some caps to specifying the desired format, or |
A sample of this's current image preview in the format given by |