-/*
- * mlt_transition.c -- abstraction for all transition services
- * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
- * Author: Charles Yates <charles.yates@pandora.be>
+/**
+ * \file mlt_transition.c
+ * \brief abstraction for all transition services
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * Copyright (C) 2003-2008 Ushodaya Enterprises Limited
+ * \author Charles Yates <charles.yates@pandora.be>
*
- * This program is distributed in the hope that it will be useful,
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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 General Public License for more details.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
*
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#include "config.h"
-
#include "mlt_transition.h"
#include "mlt_frame.h"
/** Get a frame from this transition.
- The logic is complex here. A transition is typically applied to frames on the a and
+ The logic is complex here. A transition is typically applied to frames on the a and
b tracks specified in the connect method above and only if both contain valid info
for the transition type (this is either audio or image).
+----------+-------------+
During the overlap of c1 and c2, there is nothing for the A transition to do, so this
- results in a no operation, but B is triggered. During the overlap of c2 and c3, again,
- the A transition is inactive and because the B transition is pointing at track 0,
- it too would be inactive. This isn't an ideal situation - it's better if the B
+ results in a no operation, but B is triggered. During the overlap of c2 and c3, again,
+ the A transition is inactive and because the B transition is pointing at track 0,
+ it too would be inactive. This isn't an ideal situation - it's better if the B
transition simply treats the frames from c3 as though they're the a track.
- For this to work, we cache all frames coming from all tracks between the a and b
- tracks. Before we process, we determine that the b frame contains someting of the
+ For this to work, we cache all frames coming from all tracks between the a and b
+ tracks. Before we process, we determine that the b frame contains someting of the
right type and then we determine which frame to use as the a frame (selecting a
- matching frame from a_track to b_track - 1). If both frames contain data of the
+ matching frame from a_track to b_track - 1). If both frames contain data of the
correct type, we process the transition.
This method is invoked for each track and we return the cached frames as needed.
mlt_frame b_frame_ptr = this->frames[ !reverse_order ? b_frame : a_frame ];
int a_hide = mlt_properties_get_int( MLT_FRAME_PROPERTIES( a_frame_ptr ), "hide" );
int b_hide = mlt_properties_get_int( MLT_FRAME_PROPERTIES( b_frame_ptr ), "hide" );
-
- // Process the transition
- *frame = mlt_transition_process( this, a_frame_ptr, b_frame_ptr );
-
- // We need to ensure that the tractor doesn't consider this frame for output
- if ( *frame == a_frame_ptr )
- b_hide |= type;
- else
- a_hide |= type;
-
- mlt_properties_set_int( MLT_FRAME_PROPERTIES( a_frame_ptr ), "hide", a_hide );
- mlt_properties_set_int( MLT_FRAME_PROPERTIES( b_frame_ptr ), "hide", b_hide );
+ if ( !( a_hide & type ) && !( b_hide & type ) )
+ {
+ // Process the transition
+ *frame = mlt_transition_process( this, a_frame_ptr, b_frame_ptr );
+
+ // We need to ensure that the tractor doesn't consider this frame for output
+ if ( *frame == a_frame_ptr )
+ b_hide |= type;
+ else
+ a_hide |= type;
+
+ mlt_properties_set_int( MLT_FRAME_PROPERTIES( a_frame_ptr ), "hide", a_hide );
+ mlt_properties_set_int( MLT_FRAME_PROPERTIES( b_frame_ptr ), "hide", b_hide );
+ }
}
}
-
+
// Obtain the frame from the cache or the producer we're attached to
if ( index >= a_track && index <= b_track )
*frame = this->frames[ index ];
projects / melted / blobdiff