Without this the following sequence fails:
- set_caps()
- object_stop() (does nothing)
- set_format() -> VIDIOC_S_FMT
- set_config() -> VIDIOC_REQBUFS with count = N
- set_caps()
- object_stop()
- pool_finalize()
- set_format() -> VIDIOC_S_FMT => EBUSY
Usually the pool is started after set_config(), in which case object_stop()
will result in a pool_stop and therefore VIDIOC_REQBUFS with count = 0 but
that is not guaranteed.
Also calling VIDIOC_REQBUFS with count = 0 in pool_finalize() if necessary
fixes this problem.
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701543
This is a followup patch for #700781, which is not quite correct.
The buffer handling is quite complicated here.
The original code intended to the the following:
- gst_v4l2_buffer_pool_process() calls QBUF and adds the buffer to the
local list.
- The sink calls gst_buffer_unref() which returns the buffer to the pool
but not the 'free list'.
- Some time later DQBUF returns the buffer and
gst_v4l2_buffer_pool_release_buffer() puts in on the 'free list'.
If the buffer must be copied then (parent_class)->acquire_buffer() is
called directly to keep the buffer in the pool.
This has two problems:
1. If gst_v4l2_buffer_pool_release_buffer() is called before the buffer is
returned to the pool, then the buffer is put on the 'free list' twice.
This can happen if a reference to the buffer is kept outside the sink,
of if DQBUF returns the buffer, that was just queued with QBUF.
2. If buffers are copied, then all buffers are in the pool at all times. As
a result gst_v4l2_buffer_pool_stop() and gst_v4l2_buffer_pool_dqbuf()
can access pool->buffers at the same time, which can lead to memory
corruption.
The patch for #700781 fixes those problems, but with the side effect that
there are always buffers outside the pool (because they are queued) and
the pool is never stopped.
This patch fixes this by releasing the reference to the buffer after
handling it (to avoid problem 2.) so it can be returned to the pool.
gst_v4l2_buffer_pool_release_buffer() is only called if the buffer is
already in the pool (to avoid problem 1.).
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701375
This makes it possible to set any controls that can be set with
VIDIOC_S_CTRL.
The controls are set when the property is set (if the device is open)
and when the device is opened.
https://bugzilla.gnome.org/show_bug.cgi?id=698837
Without this, a queued buffer may be required, filled and queued before it
is dequeued.
Calling gst_buffer_pool_acquire_buffer() ensures that the buffer is set up
correctly and gst_buffer_unref() calls buffer_release().
https://bugzilla.gnome.org/show_bug.cgi?id=700781
This can happen if other parts of the pipeline are reconfigured.
Stop streaming even for a short amount of time can be quite visible, so it
should be avoided if possible.
https://bugzilla.gnome.org/show_bug.cgi?id=700503
When queuing a buffer for a sink, bytesused must contain the actual
amount of data.
For a source, the driver must overwrite this, so it doesn't matter
what is set here.
https://bugzilla.gnome.org/show_bug.cgi?id=699598
In the past gst_video_info_from_caps() only video/x-raw. Now it also
supports other video/* and image/* formats.
With this patch the format won't be GST_VIDEO_FORMAT_UNKOWN and
gst_v4l2_buffer_pool_set_config() handles strides correctly.
https://bugzilla.gnome.org/show_bug.cgi?id=699570
If max_buffers is 0 then an arbitrary number of buffers (currently 4) is
allocated. If this is not enough v4l2src starts copying buffers.
With this patch VIDIOC_CREATE_BUFS is used to allocate a new buffer. If
this fails v4l2src falls back to copying buffers.
https://bugzilla.gnome.org/show_bug.cgi?id=699447
The existence of a GstVideoFormatInfo does not guarantee, that
the buffer contains video frames, so the format must be checked.
Also, for encoded buffers the length is variable and must be set.
https://bugzilla.gnome.org/show_bug.cgi?id=698949
If TRY_FMT is not implemented, gst_v4l2_object_get_nearest_size will
use S_FMT and will change the device's operation mode. To save the
old device mode we need to set the type field or else it will fail
to save the previous format.
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=685209
Set channel-mask according to sink's layout in case of stereo layout.
Also initialize and reset the mask when an unrecognized channel is detected.
https://bugzilla.gnome.org/show_bug.cgi?id=698224
Changes include the following:
* Update classname references
* Replace GST_BOILERPLATE_FULL with G_DEFINE_TYPE
* Use new GstAudioInfo struct and methods
* Use new buffer memory allocation scheme
Conflicts:
sys/osxaudio/gstosxaudioringbuffer.c
Don't just loop over the first num_queued buffers but loop over
all the buffers and check if they need to be freed. It is possible that
not all buffers are queued and then the entry in our array will be NULL.
Those buffers that are not queued were freed in stop().
Fixes https://bugzilla.gnome.org/show_bug.cgi?id=696651
