Rely on spa_pod_get_values() to return no values if the size is too
small for the type. This means that if there is a check that at least
one value is returned, checking that the size is large enough is
unnecessary.
When we simply need to change some state for the code executed in the
loop, we can use locked() instead of invoke(). This is more efficient
and avoids some context switches in the normal case.
There is no need to encode the potential format in the format.dsp of
control ports, this is just for legacy compatibility with JACK apps. The
actual format can be negotiated with the types field.
Fixes midi port visibility with apps compiled against 1.2, such as JACK
apps in flatpaks.
Rework the function a little so that it can take a list of formats and
only add the supported formats from that list and only once. It can
optionally select only the DSP formats.
Make a new PeerFormats param that can be set on ports to let it know
about the possible peer formats. This can be used by converters to calculate
an optimum conversion.
make the videoadpter query the follower formats, simplify them and then
set them as PeerFormats on the converter.
Implement peerformats in videoconvert. This makes EnumFormat on the port
depend on the negotiated format of the peer. It will suggest a Format
that most closely matches the current negotiated format with the available
PeerFormats. This then makes it possible to negotiate to the format that
would require the least amount of conversions.
Parse and use DSP formats.
Redo the conversion setup when the formats changed. We usually do this
when starting the node but the formats can change while running as well.
When there is no data and the buffer is mmapable, try to mmap it. Unmap
again when clearing the buffers.
Use the mmaped data pointer of the buffer when processing.
Keep the passthrough flag up to date when we unset a port format or when
it changes.
We should only fill in the buffer data/fd when the ALLOC flag is set.
We should only take the passthrough input buffer as output when we are
in passthrough mode.
Copy the header metadata.
To activate:
PIPEWIRE_PROPS='{ video.adapt.converter = video.convert.ffmpeg }' build/src/examples/video-play
This makes it possible to start firefox with mjpg capture and then
video-play and it will decode the mjpeg transparently. Works for other
incompatible video formats as well, as long as they can be mmapped.
Ideally this should use something GPU accelerated and this is what the
vulkan converter will do.
