Many Gstreamer elements support transforming buffers via the
`image-orientation` tag. Use it to implement support for the new
VideoTransform meta.
In order for Gstreamer pipelines to enable support for these tags
usually the rotate method has to be set to `auto` or `automatic`,
e.g. `videoflip method=automatic`, `glimagesink rotate-method=automatic`
or `waylandsink rotate-method=auto`.
Since gst_fd_allocator_alloc lazy mmap's the buffer to the assigned
file descriptor we can get downstream mmap failures if the pipewire
src(such as the v4l2 spa plugin) closes the file descriptor before
it gets mmap'd. To prevent the closed original file descriptor from
causing a mmap failure dup the file descriptor so that the original
being closed doesn't invalidate the descriptor passed to
gst_fd_allocator_alloc.
Add some more validation to dequeue_buffer as well.
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Do not use dynamic types anymore. The reason is that it's difficult:
- to maintain a shared type database over a network.
- the extra overhead when translating between processes and for
maintaining the translation tables.
- race conditions in translating in RT-threads, this is a problem
because we want to make event streams.
We now have simple enums with types and extension points for all
types. This is also nicer to use in general.
We don't need the mapper anymore or pass strings around as types.
There is a parallel type info system to get more info about ids and
enums and their hierarchy. It can also be used for debugging.
Simplify the stream API. make just 2 methods to queue and dequeue
buffers. Make just one callback when new buffers can be dequeued.
Add support for driver nodes such as the video-src.
Pass a pw_buffer structure to add/remove_buffer and make it possible
to attach metadata to it. This makes it a lot easier to implement
the gstreamer pipewire pool.
Call the stream process function from the main loop and use a lockfree
ringbuffer to pass buffers between the threads. Make it possible to
also call process from the RT thread.
unmap the buffer data when needed.
