MPEG doesn't have a static size per frame, so don't pretend it has one
and fail when capturing because it doesn't match. Instead mark the size
as unknown and let the read frame grabbing method use a reasonable fallback
value (assuming that's only for actual streaming formats)
Fixes bug #628349.
The format list should be sorted from high ranks to low ranks. In the GSList
sorting function this means the compare needs to return a positive value if
format a has a lower rank than format b.
Among other things this fixes v4l2src to prefer non-emulated formats
to emulated formats when built against libv4l.
In the case we change the State from READY_TO_NULL the buffers in the pool
still hold an open dup file descriptor to the device, therefore the device
release function will not be called and the device will probably answer with
-EBUSY when we reopen it in the next NULL_TO_READY transition.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
See bug #622500 and #612244.
This allows set_caps to succeed if caps change in a way that
would not modify the format we're getting from the hardware.
Otherwise if not in NULL state, setting caps would fail
with EBUSY.
With this change, in some cases it's OK to go PLAYING->READY->PLAYING
rather than PLAYING->NULL->PLAYING to avoid a time-consuming close
and reopen of the device.
Fixes#621723
Fixes#621723 (partially)
set_caps can fail if the video device is running, in that case
setting its format leads to EBUSY.
If set_caps fails then we will not have set up the buffer pool
(it will be NULL) which leads to a crash when we try to pull
buffers. If we fail the negotiate on set_caps failure, then we
won't go to playing state and won't crash.
This is a small improvement. Of course, a nicer fix would
be to make set_caps work in the case where the format is
unchanged. If the format has changed, failing is
probably correct because we need to close the device
(go to NULL state) in order to set caps.
The compiler wants a cast here even though the type is already
typedefed as 64-bit integer (presumably because glib has typedefed
guint64 to unsigned long here).
Don't leak a string everytime get_uri() is called and a device
has been set. There's a limited number of devices, so just
intern the string instead of doing more elaborate housekeeping
and storing it in the instance struct or so.
Old videodevice2.h kernel headers used ioctl stuff without
including ioctl.h, making compilation fail on older systems.
Note: Including ioctl.h here is only a workaround for old kernel
headers, should be removed once everybody has new enough headers.
Fixes bug #597867.
For cameras/drivers that don't support e.g. VIDIOC_G_PARM we'd end up without
a framerate and would try to divide by 0, causing run-time warnings and all
frames to be timestamped with 0, which makes sinks that sync against the clock
drop them, causing 'hangs' (observed with the pwc driver and a Logitech QuickCam
Pro 4000). So if we do not know the framerate, simply don't adjust the
timestamps. Fixes#591451.
Clear format list and probed caps when going to NULL so if a new device
is set we'll probe the formats again instead of using previously
detected ones. Fixes bug #591747.
It seems to cause strange occasional high latencies (almost 200ms) when dequeuing buffers from _buffer_alloc(). It is simpler and seems to work much better to dqbuf from the same thread that is queuing the next buffer.
This also does the following changes:
(1) pull the bufferpool code out into gstv4l2bufferpool.c, and make a
bit more generic so it can be used both for v4l2src and v4l2sink
(2) move some of the device probing/configuration/caps stuff into
gstv4l2object.c so it does not have to be duplicated between
v4l2src and v4l2sink
Fixes bug #590280.
