Image previews where being posted in sync with the buffers
timestamps, this makes no sense as previews should be posted ASAP.
Also adds some debugging messages.
Camerabin2 uses state changes to force the source to renegotiate its
caps to the capture formats. The state changes makes the source lose
its clock and base_time, causing it to stop timestamping the buffers.
We still need a proper way to make sources renegotiate its caps, so this
patch is a hack to make the source continue timestamping buffers even
after changing state. The patch works by getting the clock and base
time before doing the state change to NULL and setting them back
after putting it to PLAYING again. It also cares to drop the first
new segment after this state change.
Implement previewing functionality using 2 properties. A boolean
(post-previews) that indicates if previews should be posted, and a
GstCaps (preview-caps) to provide the desired preview caps.
wrappercamerabinsrc implements previewing by supplying the captured
image to a pipeline to adapt it to the required caps before posting.
Instead of linking 3 src pads from tee to the ghostpads, use 2
srcpads and add an output-selector to completely split caps
negotiation of video/image modes. I don't think there is an
use case that would require image and video pads to be used
at the same time.