static GstStateChangeReturn
gst_v4l2sink_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstV4l2Sink *v4l2sink = GST_V4L2SINK (element);
GST_DEBUG_OBJECT (v4l2sink, "%d -> %d",
GST_STATE_TRANSITION_CURRENT (transition),
GST_STATE_TRANSITION_NEXT (transition));
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
/* open the device */
if (!gst_v4l2_object_start (v4l2sink->v4l2object))
return GST_STATE_CHANGE_FAILURE;
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
if (v4l2sink->state == STATE_STREAMING) {
if (!gst_v4l2_object_stop_streaming (v4l2sink->v4l2object)) {
return GST_STATE_CHANGE_FAILURE;
}
v4l2sink->state = STATE_PENDING_STREAMON;
}
break;
case GST_STATE_CHANGE_READY_TO_NULL:
if (NULL != v4l2sink->pool)
gst_v4l2_buffer_pool_destroy (v4l2sink->pool);
v4l2sink->pool = NULL;
/* close the device */
if (!gst_v4l2_object_stop (v4l2sink->v4l2object))
return GST_STATE_CHANGE_FAILURE;
v4l2sink->state = STATE_OFF;
break;
default:
break;
}
return ret;
}
/******************************************************
* gst_v4l2src_capture_deinit():
* deinitialize the capture system
* return value: TRUE on success, FALSE on error
******************************************************/
gboolean
gst_v4l2src_capture_deinit (GstV4l2Src * v4l2src)
{
GST_DEBUG_OBJECT (v4l2src, "deinitting capture system");
if (!GST_V4L2_IS_OPEN (v4l2src->v4l2object)) {
return TRUE;
}
if (!GST_V4L2_IS_ACTIVE (v4l2src->v4l2object)) {
return TRUE;
}
if (v4l2src->pool) {
gst_v4l2_buffer_pool_destroy (v4l2src->pool);
v4l2src->pool = NULL;
}
GST_V4L2_SET_INACTIVE (v4l2src->v4l2object);
return TRUE;
}
/**
* gst_v4l2_buffer_pool_new:
* @v4l2elem: the v4l2 element (src or sink) that owns this pool
* @fd: the video device file descriptor
* @num_buffers: the requested number of buffers in the pool
* @caps: the caps to set on the buffer
* @requeuebuf: if %TRUE, and if the pool is still in the running state, a
* buffer with no remaining references is immediately passed back to v4l2
* (VIDIOC_QBUF), otherwise it is returned to the pool of available buffers
* (which can be accessed via gst_v4l2_buffer_pool_get().
*
* Construct a new buffer pool.
*
* Returns: the new pool, use gst_v4l2_buffer_pool_destroy() to free resources
*/
GstV4l2BufferPool *
gst_v4l2_buffer_pool_new (GstElement * v4l2elem, gint fd, gint num_buffers,
GstCaps * caps, gboolean requeuebuf, enum v4l2_buf_type type)
{
GstV4l2BufferPool *pool;
gint n;
struct v4l2_requestbuffers breq;
pool = (GstV4l2BufferPool *) gst_mini_object_new (GST_TYPE_V4L2_BUFFER_POOL);
pool->video_fd = v4l2_dup (fd);
if (pool->video_fd < 0)
goto dup_failed;
/* first, lets request buffers, and see how many we can get: */
GST_DEBUG_OBJECT (v4l2elem, "STREAMING, requesting %d MMAP buffers",
num_buffers);
memset (&breq, 0, sizeof (struct v4l2_requestbuffers));
breq.type = type;
breq.count = num_buffers;
breq.memory = V4L2_MEMORY_MMAP;
if (v4l2_ioctl (fd, VIDIOC_REQBUFS, &breq) < 0)
goto reqbufs_failed;
GST_LOG_OBJECT (v4l2elem, " count: %u", breq.count);
GST_LOG_OBJECT (v4l2elem, " type: %d", breq.type);
GST_LOG_OBJECT (v4l2elem, " memory: %d", breq.memory);
if (breq.count < GST_V4L2_MIN_BUFFERS)
goto no_buffers;
if (num_buffers != breq.count) {
GST_WARNING_OBJECT (v4l2elem, "using %u buffers instead", breq.count);
num_buffers = breq.count;
}
pool->v4l2elem = v4l2elem;
pool->requeuebuf = requeuebuf;
pool->type = type;
pool->buffer_count = num_buffers;
pool->buffers = g_new0 (GstV4l2Buffer *, num_buffers);
pool->avail_buffers = g_async_queue_new ();
/* now, map the buffers: */
for (n = 0; n < num_buffers; n++) {
pool->buffers[n] = gst_v4l2_buffer_new (pool, n, caps);
if (!pool->buffers[n])
goto buffer_new_failed;
pool->num_live_buffers++;
g_async_queue_push (pool->avail_buffers, pool->buffers[n]);
}
return pool;
/* ERRORS */
dup_failed:
{
gint errnosave = errno;
gst_mini_object_unref (GST_MINI_OBJECT (pool));
errno = errnosave;
return NULL;
}
reqbufs_failed:
{
GstV4l2Object *v4l2object = get_v4l2_object (v4l2elem);
GST_ELEMENT_ERROR (v4l2elem, RESOURCE, READ,
(_("Could not get buffers from device '%s'."),
v4l2object->videodev),
("error requesting %d buffers: %s", num_buffers, g_strerror (errno)));
return NULL;
}
no_buffers:
{
GstV4l2Object *v4l2object = get_v4l2_object (v4l2elem);
GST_ELEMENT_ERROR (v4l2elem, RESOURCE, READ,
(_("Could not get enough buffers from device '%s'."),
v4l2object->videodev),
("we received %d from device '%s', we want at least %d",
breq.count, v4l2object->videodev, GST_V4L2_MIN_BUFFERS));
return NULL;
}
buffer_new_failed:
{
gint errnosave = errno;
gst_v4l2_buffer_pool_destroy (pool);
errno = errnosave;
return NULL;
}
}
