Most v4l2 drivers will get upset when you queue the same buffer twice in a
row without first dequeueing it.
Rendering of pre-roll buffers can be re-introduced later, but will require
tracking the state of the buffer, and avoiding to re-QBUF if the buffer has
already been passed to the driver.
When the decoder is using pad_alloc(), v4l2sink would behave badly if
the number of buffers ('queue-size' property) was not high enough to
account for all the buffers needed by the decoder, and other elements
(such as queues) between the decoder and v4l2sink. This patch
slightly increases the default number of buffers, and changes v4l2sink
to drop frames rather than return an error in case the number of
buffers is not high enough.
ximagesrc: fix various width/height calculations being off by one,
and make it so a single pixel width/height can be captured (except
the top left one, as 0,0,0,0 is reserved for full screen as per
the property comments).
with i686-apple-darwin10-gcc-4.2.1:
gstv4l2object.c: In function 'gst_v4l2_object_get_nearest_size':
gstv4l2object.c:1988: warning: format '%u' expects type 'unsigned int', but argument 12 has type 'gint *'
gstv4l2object.c:1988: warning: format '%u' expects type 'unsigned int', but argument 13 has type 'gint *'
it's perfectly ok for a video output device to not have overlay capabilities.
this patch removes the need to get/set the overlay parameters if the user
does not explicitely request one of the overlay properties
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.
"Low" etc. are quality settings here (e.g. for the internal resampler).
Some day when we use GLib's i18n functions we might want to use
NC_() and g_dpgettext2() here instead of the comments.
Fixes#555967.
OSS4 supports per-stream volume control, so expose this using the right
API, so that playbin2 and applications like totem can make use of it
(instead of using a volume element for volume control).
Fixes#614305.
When iterating the formats table, we can just pass the whole
entry to our helper function, which avoids iterating the table
again to find the entry structure from the passed format id.
Also accept formats that are not natively supported by the
hardware, OSS4 can convert them internally. List the native
formats first in the caps though, to express our preference
for the native formats. We need this in order to support the
case properly where the audio hardware supports only e.g.
little endian PCM, but the host is big endian, since many
audio elements only support native endianness and make the
reasonable assumption that any audiosink will be able to
handle audio in native endianness.
Based on patch by Jerry Tan <jerry.tan@sun.com>
Fixes#614317.
A side effect is that it passes -Wformat-nonliteral and doesn't read
invalid memory in some cases, like when the mixer track contains
a % sign or there is a number but not a known mixer name.
