/* * GStreamer * Copyright (C) 2008 Nokia Corporation <multimedia@maemo.org> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ /** * SECTION:camerabingeneral * @title: GstCameraBin2 * @short_description: helper functions for #GstCameraBin2 and it's modules * * Common helper functions for #GstCameraBin2, #GstCameraBin2Image and * #GstCameraBin2Video. * */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include <string.h> #include <glib.h> #include <gst/basecamerabinsrc/gstbasecamerasrc.h> #include <glib/gi18n-lib.h> #include "camerabingeneral.h" /** * gst_camerabin_add_element: * @bin: add an element to this bin * @new_elem: new element to be added * * Adds given element to given @bin. Looks for an unconnected src pad * from the @bin and links the element to it. Raises an error if adding * or linking failed. Unrefs the element in the case of an error. * * Returns: %TRUE if adding and linking succeeded, %FALSE otherwise. */ gboolean gst_camerabin_add_element (GstBin * bin, GstElement * new_elem) { return gst_camerabin_add_element_full (bin, NULL, new_elem, NULL); } /** * gst_camerabin_add_element_full: * @bin: add an element to this bin * @srcpad: src pad name, or NULL for any * @new_elem: new element to be added * @dstpad: dst pad name, or NULL for any * * Adds given element to given @bin. Looks for an unconnected src pad * (with name @srcpad, if specified) from the @bin and links the element * to it. Raises an error if adding or linking failed. Unrefs the element * in the case of an error. * * Returns: %TRUE if adding and linking succeeded, %FALSE otherwise. */ gboolean gst_camerabin_add_element_full (GstBin * bin, const gchar * srcpad, GstElement * new_elem, const gchar * dstpad) { gboolean ret; g_return_val_if_fail (bin, FALSE); g_return_val_if_fail (new_elem, FALSE); ret = gst_camerabin_try_add_element (bin, srcpad, new_elem, dstpad); if (!ret) { gchar *elem_name = gst_element_get_name (new_elem); GST_ELEMENT_ERROR (bin, CORE, NEGOTIATION, (NULL), ("linking %s failed", elem_name)); g_free (elem_name); gst_object_unref (new_elem); } return ret; } /** * gst_camerabin_try_add_element: * @bin: tries adding an element to this bin * @srcpad: src pad name, or NULL for any * @new_elem: new element to be added * @dstpad: dst pad name, or NULL for any * * Adds given element to given @bin. Looks for an unconnected src pad * (with name @srcpad, if specified) from the @bin and links the element to * it. * * Returns: %TRUE if adding and linking succeeded, %FALSE otherwise. */ gboolean gst_camerabin_try_add_element (GstBin * bin, const gchar * srcpad, GstElement * new_elem, const gchar * dstpad) { GstPad *bin_pad; GstElement *bin_elem; gboolean ret = TRUE; g_return_val_if_fail (bin, FALSE); g_return_val_if_fail (new_elem, FALSE); /* Get pads for linking */ bin_pad = gst_bin_find_unlinked_pad (bin, GST_PAD_SRC); /* Add to bin */ gst_bin_add (GST_BIN (bin), new_elem); /* Link, if unconnected pad was found, otherwise just add it to bin */ if (bin_pad) { GST_DEBUG_OBJECT (bin, "linking %s to %s:%s", GST_OBJECT_NAME (new_elem), GST_DEBUG_PAD_NAME (bin_pad)); bin_elem = gst_pad_get_parent_element (bin_pad); gst_object_unref (bin_pad); if (!gst_element_link_pads_full (bin_elem, srcpad, new_elem, dstpad, GST_PAD_LINK_CHECK_CAPS)) { gst_object_ref (new_elem); gst_bin_remove (bin, new_elem); ret = FALSE; } gst_object_unref (bin_elem); } else { GST_INFO_OBJECT (bin, "no unlinked source pad in bin"); } return ret; } /** * gst_camerabin_create_and_add_element: * @bin: tries adding an element to this bin * @elem_name: name of the element to be created * @instance_name: name of the instance of the element to be created * * Creates an element according to given name and * adds it to given @bin. Looks for an unconnected src pad * from the @bin and links the element to it. * * Returns: pointer to the new element if successful, NULL otherwise. */ GstElement * gst_camerabin_create_and_add_element (GstBin * bin, const gchar * elem_name, const gchar * instance_name) { GstElement *new_elem; g_return_val_if_fail (bin, FALSE); g_return_val_if_fail (elem_name, FALSE); new_elem = gst_element_factory_make (elem_name, instance_name); if (!new_elem) { GST_ELEMENT_ERROR (bin, CORE, MISSING_PLUGIN, (_("Missing element '%s' - check your GStreamer installation."), elem_name), (NULL)); } else if (!gst_camerabin_add_element (bin, new_elem)) { new_elem = NULL; } return new_elem; } /* try to change the state of an element. This function returns the element * when the state change could be performed. When this function returns NULL * an error occurred and the element is unreffed. */ static GstElement * try_element (GstElement * bin, GstElement * element) { GstStateChangeReturn ret; if (element) { ret = gst_element_set_state (element, GST_STATE_READY); if (ret == GST_STATE_CHANGE_FAILURE) { GST_DEBUG_OBJECT (bin, "failed state change.."); gst_element_set_state (element, GST_STATE_NULL); gst_object_unref (element); element = NULL; } } return element; } GstElement * gst_camerabin_setup_default_element (GstBin * bin, GstElement * user_elem, const gchar * auto_elem_name, const gchar * default_elem_name, const gchar * instance_name) { GstElement *elem; if (user_elem) { GST_DEBUG_OBJECT (bin, "trying configured element"); elem = try_element (GST_ELEMENT_CAST (bin), gst_object_ref (user_elem)); } else { /* only try fallback if no specific sink was chosen */ GST_DEBUG_OBJECT (bin, "trying %s", auto_elem_name); elem = gst_element_factory_make (auto_elem_name, instance_name); elem = try_element (GST_ELEMENT_CAST (bin), elem); if (elem == NULL) { /* if default sink from config.h is different then try it too */ if (strcmp (default_elem_name, auto_elem_name)) { GST_DEBUG_OBJECT (bin, "trying %s", default_elem_name); elem = gst_element_factory_make (default_elem_name, instance_name); elem = try_element (GST_ELEMENT_CAST (bin), elem); } } } return elem; } /** * gst_camerabin_remove_elements_from_bin: * @bin: removes all elements from this bin * * Removes all elements from this @bin. */ void gst_camerabin_remove_elements_from_bin (GstBin * bin) { GstIterator *iter = NULL; GValue value = { 0 }; GstElement *elem = NULL; gboolean done = FALSE; iter = gst_bin_iterate_elements (bin); while (!done) { switch (gst_iterator_next (iter, &value)) { case GST_ITERATOR_OK: elem = (GstElement *) g_value_get_object (&value); gst_bin_remove (bin, elem); gst_element_set_state (GST_ELEMENT (elem), GST_STATE_NULL); /* Iterator increased the element refcount, so unref */ g_value_unset (&value); break; case GST_ITERATOR_RESYNC: gst_iterator_resync (iter); break; case GST_ITERATOR_ERROR: GST_WARNING_OBJECT (bin, "error in iterating elements"); done = TRUE; break; case GST_ITERATOR_DONE: done = TRUE; break; } } gst_iterator_free (iter); }