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; } }