In kernel before 3.17, polling during queue underrun would unblock right
away and trigger POLLERR. As we are not handling POLLERR, we would endup
blocking in DQBUF call, which won't be unblocked correctly when going
to NULL state. A deadlock at start caused by locking error in libv4l2 was
also seen before this patch. Instead, we wait until the queue is no longer
empty before polling.
https://bugzilla.gnome.org/show_bug.cgi?id=731015
The code enumerating STEPWISE framesizes would start from
(min_w, min_h) and then add (step_w, step_h) to get the
next framesize. However, it should really allow any width
from min_w to max_w with step_w and same for heights.
Secondly, we would add and probe each individual stepped
frame size to the caps as separate structure, which would
lead to hundreds if not thousands of structs ending up in
the probed caps. Use integer ranges with steps instead.
This was particularly noticable with the Raspberry Pi Cam.
https://bugzilla.gnome.org/show_bug.cgi?id=724521https://bugzilla.gnome.org/show_bug.cgi?id=732458https://bugzilla.gnome.org/show_bug.cgi?id=726521
This workaround from 2011 was causing 25 S_FMT ioctls to be sent
to my UVC webcam from under gst_v4l2_object_get_caps as it probes
all the formats. In total, this adds up to about 5 seconds of
execution time, or a 10 second delay while starting up cheese.
These ioctls come from a workaround from 2011 where TRY_FMT might
make changes to hardware settings, so S_FMT was used to restore
the original config:
https://bugzilla.gnome.org/show_bug.cgi?id=649067
The driver bug is now assumed fixed. Remove the workaround to fix the
long startup delay.
https://bugzilla.gnome.org/show_bug.cgi?id=732326
This is required as during preroll we pass the first buffer twice, hence already
queued. It is also useful, to allow filters replaying a previous rendered buffers.
This will require 1 more buffer in sink if last-sample is enabled, since the last
sample will not be the same as the currently queued buffer.
https://bugzilla.gnome.org/show_bug.cgi?id=722303
For output device, we where queuing all the buffers, and then we would
dequeue one. This means we only have 1 buffer for the pipeline, no matter
the size of the queue. Instead, start dequeued when min_latency is reached.
Eventually, this the min_latency should also be affected by control
MIN_BUFFERS_FOR_OUTPUT (use by encoders).
Calculation of num_buffers (the max latency in buffers) was
up-side-down. If we can allcoate, then our maximum latency match
pool maximum number of buffers. Also renamed it to max latency. Finally
introduced a min_latency for clarity.
Fix the choice of min/max, don't override the min/max with own pool selected
size, correct other_pool is_active check, start from other_pool config when
configuring the other pool and finally validate the configuration.
The decodeing thread returning flushing isn't an error, we should simply
try starting the task again. If it's actually flushing, it will stop again by itself.
gstv4l2bufferpool.c:608:18: error: implicit conversion from enumeration type
'enum _GstV4l2BufferPoolAcquireFlags' to different enumeration type
'GstBufferPoolAcquireFlags' [-Werror,-Wenum-conversion]
params.flags = GST_V4L2_POOL_ACQUIRE_FLAG_RESURECT;
~ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We need to handle the case where a flush occure while the streaming
thread is being brought up. In this case, the flushing state of the poll
object is cleared. To solve this, we simply set the capture poll to flushing
again, this way we know the thread will exit. The decoder streamlock
is used to synchronize with handle frame.
M2M devices were sharing the same properties as src and sink. Most of
these made no sense. This patch reduces the number of propeties and
makes io-mode clearer by having capture-io-mode and output-io-mode. This
also accidently fixed a bug in gstv4l2transform io-mode code, where the
capture io-mode could not be set.
https://bugzilla.gnome.org/show_bug.cgi?id=729591
If the driver need more buffers than requested by the config,
update the pool min/max values. The minimum value for the pool
could be provided either by the driver or by the pool. This is
best effort for drivers that don't support
CID V4L2_CID_MIN_BUFFERS_FOR_CAPTURE.
https://bugzilla.gnome.org/show_bug.cgi?id=730200
This allow calling start streaming later for capture device. Currently it breaks
in dmabuf-import because downstream is holding a buffer that will only be
released after stream-start.
https://bugzilla.gnome.org/show_bug.cgi?id=730207
When extrapolating the offset, we need to use the extrapolate
stride rather then the base stride. This should fix support for format
with more then two planes (I420, Y42B, etc).
When doing frame operation, we need to use the default VideoInfo
and let the frame API read the video meta in order to get the stride
and offset right. Currently we where using the specialized VideoInfo
which reflects what the HW is setup to.
Simplify framerate field if possible, so we don't end up with
e.g. framerate = (fraction) { 30/1 }. Maybe the helper function
should be moved to core, but we can do this later.
This moves away from copying information and store everything inside
the GstVideoInfo structure. The alignement exposed by v4l2 api
is now handled using proper offset.
Return a buffer from an otherpool has unwanted side effects that lead to leaks and
prevents deactivating the pool. Instead, we change the _process() API so it can
replace the internal buffer with the buffer from the downstream pool. This implied
moving from _fill() to _create() method in the src.
Buffer refcounting is a bit hard, because of the duality between CAPTURE and
OUTPUT mode. In the long term, we should consider having two seperate pool
instead of this mess. At least state should be better kept this way.
All enum that has REQBUFS and CREATE_BUFS where missing S, which was
confusing since they are supposed to match with associcated ioctl name. This
also fixes the yet unused CAN_REQUEST flag check.
Because of the buf in videobuf2, dqbuf may leave the DONE flag being,
which would implied that the buffer is queued. As this has been broken
for 4 years, simply guaranty the state flags integrity when doing
qbuf/dqbuf.
See https://patchwork.linuxtv.org/patch/23641/
Improve decide allocation so it properly configure both local and downstream
buffer pools. Also read back the pool config if it was changed to to driver
limitations.
Pre-configuring the pool is error prone, since it may hide a configuration failure and
endup with a pool that is not configured the way it should (e.g. no video meta, wrong
queue size, etc.)
Catch short allocation after saving the format. This is not a catch all, but should catch
most of the miss-behaving drivers when doing S_FMT/G_FMT and avoid potential crash.
This goal of this allocator is mainly to allow tracking the memory.
Currently, when a buffer memory has been modified, the buffer and it's
memory is disposed and lost until the stream is restarted.
