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add API to make life easier
Original commit message from CVS: add API to make life easier
This commit is contained in:
Benjamin Otte
parent
780213e23a
commit
9d34e82b9a
4 changed files with 249 additions and 0 deletions
169
gst/gstelement.c
169
gst/gstelement.c
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@ -697,6 +697,175 @@ gst_element_request_pad_by_name (GstElement *element, const gchar *name)
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return pad;
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}
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/**
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* gst_element_get_compatible_pad_filtered:
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* @element: the element in which the pad should be found
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* @pad: the pad to find a compatible one for
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* @filtercaps: the caps to use as a filter
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*
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* Looks for an unconnected pad to which the given pad can connect to.
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* It is not guaranteed that connecting the pads will work, though
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* it should work in most cases.
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*
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* Returns: the pad to which a connection can be made
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*/
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GstPad*
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gst_element_get_compatible_pad_filtered (GstElement *element, GstPad *pad, GstCaps *filtercaps)
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{
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GList *pads;
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GstPadTemplate *templ;
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GstCaps *intersection;
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GstPad *foundpad = NULL;
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/* checks */
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g_return_val_if_fail (element != NULL, NULL);
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g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
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g_return_val_if_fail (pad != NULL, NULL);
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g_return_val_if_fail (GST_IS_PAD (pad), NULL);
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/* let's use the real pad */
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pad = (GstPad *) GST_PAD_REALIZE (pad);
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g_return_val_if_fail (pad != NULL, NULL);
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g_return_val_if_fail (GST_RPAD_PEER (pad) == NULL, NULL);
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/* try to get an existing unconnected pad */
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pads = gst_element_get_pad_list (element);
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while (pads)
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{
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GstPad *current = GST_PAD (pads->data);
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if ((GST_PAD_PEER (GST_PAD_REALIZE (current)) == NULL) &&
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gst_pad_can_connect_filtered (pad, current, filtercaps))
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{
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return current;
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}
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pads = g_list_next (pads);
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}
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/* try to create a new one */
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/* requesting is a little crazy, we need a template. Let's create one */
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if (filtercaps != NULL)
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{
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filtercaps = gst_caps_intersect (filtercaps, (GstCaps *) GST_RPAD_CAPS (pad));
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if (filtercaps == NULL)
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return NULL;
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}
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templ = gst_padtemplate_new ((gchar *) GST_PAD_NAME (pad), GST_RPAD_DIRECTION (pad),
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GST_PAD_ALWAYS, filtercaps);
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foundpad = gst_element_request_compatible_pad (element, templ);
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gst_object_unref (GST_OBJECT (templ));
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if (filtercaps != NULL)
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gst_caps_unref (filtercaps);
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return foundpad;
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}
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/**
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* gst_element_get_compatible_pad:
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* @element: the element in which the pad should be found
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* @pad: the pad to find a compatible one for
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*
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* Looks for an unconnected pad to which the given pad can connect to.
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* It is not guaranteed that connecting the pads will work, though
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* it should work in most cases.
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*
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* Returns: the pad to which a connection can be made
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*/
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GstPad*
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gst_element_get_compatible_pad (GstElement *element, GstPad *pad)
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{
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return gst_element_get_compatible_pad_filtered (element, pad, NULL);
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}
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/**
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* gst_element_connect_elements:
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* @src: the element containing source pad
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* @dest: the element containing destination pad
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* @filtercaps: the caps to use as filter
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*
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* Connect the source to the destination element using the filtercaps.
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* The connection must be from source to destination, the other
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* direction will not be tried.
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* The functions looks for existing pads that aren't connected yet.
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+ It will use request pads if possible. But both pads will not be requested.
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* If multiple connections are possible, only one is established.
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*
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* Return: TRUE if the elements could be connected.
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*/
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gboolean
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gst_element_connect_elements_filtered (GstElement *src, GstElement *dest,
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GstCaps *filtercaps)
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{
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GList *srcpads, *destpads;
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GstPad *srcpad, *destpad;
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/* checks */
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g_return_val_if_fail (src != NULL, FALSE);
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g_return_val_if_fail (GST_IS_ELEMENT(src), FALSE);
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g_return_val_if_fail (dest != NULL, FALSE);
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g_return_val_if_fail (GST_IS_ELEMENT(dest), FALSE);
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GST_DEBUG (GST_CAT_ELEMENT_PADS, "attempting to connect element %s to element %s\n", GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
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/* loop through the existing pads in the source */
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srcpads = gst_element_get_pad_list (src);
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while (srcpads)
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{
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srcpad = (GstPad *) GST_PAD_REALIZE (srcpads->data);
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if ((GST_RPAD_DIRECTION (srcpad) == GST_PAD_SRC) &&
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(GST_PAD_PEER (srcpad) == NULL))
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{
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destpad = gst_element_get_compatible_pad_filtered (dest, srcpad, filtercaps);
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if (destpad && gst_pad_connect_filtered (srcpad, destpad, filtercaps))
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{
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GST_DEBUG (GST_CAT_ELEMENT_PADS, "connected pad %s:%s to pad %s:%s\n", GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (destpad));
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return TRUE;
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}
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}
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srcpads = g_list_next (srcpads);
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}
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/* loop through the existing pads in the destination */
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destpads = gst_element_get_pad_list (dest);
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while (destpads)
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{
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destpad = (GstPad *) GST_PAD_REALIZE (destpads->data);
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if ((GST_RPAD_DIRECTION (destpad) == GST_PAD_SINK) &&
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(GST_PAD_PEER (destpad) == NULL))
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{
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srcpad = gst_element_get_compatible_pad_filtered (src, destpad, filtercaps);
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if (srcpad && gst_pad_connect_filtered (srcpad, destpad, filtercaps))
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{
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GST_DEBUG (GST_CAT_ELEMENT_PADS, "connected pad %s:%s to pad %s:%s\n", GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (destpad));
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return TRUE;
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}
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}
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destpads = g_list_next (destpads);
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}
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GST_DEBUG (GST_CAT_ELEMENT_PADS, "no connection possible from %s to %s\n", GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (dest));
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return FALSE;
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}
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/**
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* gst_element_connect_elements:
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* @src: element containing source pad
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* @dest: element containing destination pad
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*
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* Connect the source to the destination element.
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* The connection must be from source to destination, the other
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* direction will not be tried.
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* The functions looks for existing pads and request pads that aren't
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* connected yet. If multiple connections are possible, only one is
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* established.
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*
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* Return: TRUE if the elements could be connected.
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*/
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gboolean
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gst_element_connect_elements (GstElement *src, GstElement *dest)
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{
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return gst_element_connect_elements_filtered (src, dest, NULL);
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}
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/**
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* gst_element_connect_filtered:
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* @src: element containing source pad
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@ -199,7 +199,14 @@ void gst_element_remove_ghost_pad (GstElement *element, GstPad *pad);
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GstPad* gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ);
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GstPad* gst_element_request_pad_by_name (GstElement *element, const gchar *name);
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GstPad* gst_element_get_compatible_pad_filtered (GstElement *element, GstPad *pad,
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GstCaps *filtercaps);
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GstPad* gst_element_get_compatible_pad (GstElement *element, GstPad *pad);
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/* these functions should probably have another name, but gst_element_connect is already used */
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gboolean gst_element_connect_elements (GstElement *src, GstElement *dest);
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gboolean gst_element_connect_elements_filtered (GstElement *src, GstElement *dest,
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GstCaps *filtercaps);
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gboolean gst_element_connect (GstElement *src, const gchar *srcpadname,
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GstElement *dest, const gchar *destpadname);
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gboolean gst_element_connect_filtered (GstElement *src, const gchar *srcpadname,
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70
gst/gstpad.c
70
gst/gstpad.c
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@ -573,6 +573,76 @@ gst_pad_disconnect (GstPad *srcpad,
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GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
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}
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/**
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* gst_pad_can_connect_filtered:
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* @srcpad: the source pad to connect
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* @sinkpad: the sink pad to connect
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* @filtercaps: the filter caps.
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*
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* Checks if the source pad and the sink pad can be connected.
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* The filter indicates the media type that should flow trought this connection.
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*
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* Returns: TRUE if the pad can be connected, FALSE otherwise
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*/
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gboolean
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gst_pad_can_connect_filtered (GstPad *srcpad, GstPad *sinkpad, GstCaps *filtercaps)
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{
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gint num_decoupled = 0;
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GstRealPad *realsrc, *realsink;
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/* generic checks */
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g_return_val_if_fail (srcpad != NULL, FALSE);
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g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
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g_return_val_if_fail (sinkpad != NULL, FALSE);
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g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
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/* now we need to deal with the real/ghost stuff */
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realsrc = GST_PAD_REALIZE (srcpad);
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realsink = GST_PAD_REALIZE (sinkpad);
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g_return_val_if_fail (GST_RPAD_PEER (realsrc) == NULL, FALSE);
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g_return_val_if_fail (GST_RPAD_PEER (realsink) == NULL, FALSE);
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g_return_val_if_fail (GST_PAD_PARENT (realsrc) != NULL, FALSE);
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g_return_val_if_fail (GST_PAD_PARENT (realsink) != NULL, FALSE);
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if (realsrc->sched && realsink->sched) {
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if (GST_FLAG_IS_SET (GST_PAD_PARENT (realsrc), GST_ELEMENT_DECOUPLED))
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num_decoupled++;
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if (GST_FLAG_IS_SET (GST_PAD_PARENT (realsink), GST_ELEMENT_DECOUPLED))
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num_decoupled++;
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if (realsrc->sched != realsink->sched && num_decoupled != 1) {
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g_warning ("connecting pads with different scheds requires exactly one decoupled element (queue)\n");
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return FALSE;
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}
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}
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/* check if the directions are compatible */
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if (!(((GST_RPAD_DIRECTION (realsrc) == GST_PAD_SINK) &&
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(GST_RPAD_DIRECTION (realsink) == GST_PAD_SRC)) ||
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((GST_RPAD_DIRECTION (realsrc) == GST_PAD_SRC) &&
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(GST_RPAD_DIRECTION (realsink) == GST_PAD_SINK))))
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{
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return FALSE;
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}
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return TRUE;
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}
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/**
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* gst_pad_can_connect:
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* @srcpad: the source pad to connect
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* @sinkpad: the sink pad to connect
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*
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* Checks if the source pad can be connected to the sink pad.
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*
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* Returns: TRUE if the pads can be connected, FALSE otherwise
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*/
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gboolean
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gst_pad_can_connect (GstPad *srcpad, GstPad *sinkpad)
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{
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return gst_pad_can_connect_filtered (srcpad, sinkpad, NULL);
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}
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/**
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* gst_pad_connect_filtered:
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* @srcpad: the source pad to connect
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@ -385,6 +385,9 @@ GstPad* gst_pad_get_peer (GstPad *pad);
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GstBufferPool* gst_pad_get_bufferpool (GstPad *pad);
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gboolean gst_pad_can_connect (GstPad *srcpad, GstPad *sinkpad);
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gboolean gst_pad_can_connect_filtered (GstPad *srcpad, GstPad *sinkpad, GstCaps *filtercaps);
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gboolean gst_pad_connect (GstPad *srcpad, GstPad *sinkpad);
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gboolean gst_pad_connect_filtered (GstPad *srcpad, GstPad *sinkpad, GstCaps *filtercaps);
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void gst_pad_disconnect (GstPad *srcpad, GstPad *sinkpad);
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