Uploaded splitter/combiner API draft

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@488 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjmedia/include/pjmedia/splitcomb.h b/pjmedia/include/pjmedia/splitcomb.h
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+++ b/pjmedia/include/pjmedia/splitcomb.h
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+/* $Id$ */
+/* 
+ * Copyright (C) 2003-2006 Benny Prijono <benny@prijono.org>
+ *
+ * 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.
+ *
+ * This program 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.
+ *
+ * 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 
+ */
+#ifndef __PJMEDIA_SPLITCOMB_H__
+#define __PJMEDIA_SPLITCOMB_H__
+
+
+/**
+ * Create a media splitter/combiner with the specified parameters.
+ * A splitter/combiner splits a single stereo/multichannel audio frame into
+ * multiple mono audio frames to each channel when put_frame() is called, 
+ * and combines mono frames from each channel into a stereo/multichannel 
+ * frame when get_frame() is called.
+ *
+ * When the splitter/combiner is created, it creates an instance of
+ * pjmedia_port. This media port represents the stereo/multichannel side
+ * of the splitter/combiner. Application needs to supply the splitter/
+ * combiner with a media port for each audio channels.
+ *
+ * @param pool		    Pool to allocate memory to create the splitter/
+ *			    combiner.
+ * @param clock_rate	    Audio clock rate/sampling rate.
+ * @param channel_count	    Number of channels.
+ * @param samples_per_frame Number of samples per frame.
+ * @param bits_per_sample   Bits per sample.
+ * @param options	    Optional flags.
+ * @param p_splitcomb	    Pointer to receive the splitter/combiner.
+ *
+ * @return		    PJ_SUCCESS on success, or the appropriate
+ *			    error code.
+ */
+PJ_DECL(pj_status_t) pjmedia_splitcomb_create(pj_pool_t *pool,
+					      unsigned clock_rate,
+					      unsigned channel_count,
+					      unsigned samples_per_frame,
+					      unsigned bits_per_sample,
+					      unsigned options,
+					      pjmedia_port **p_splitcomb);
+
+/**
+ * Supply the splitter/combiner with media port for the specified channel 
+ * number. The media port will be called at the
+ * same phase as the splitter/combiner; which means that when application
+ * calls get_frame() of the splitter/combiner, it will call get_frame()
+ * for all ports that have the same phase. And similarly for put_frame().
+ *
+ * @param splitcomb	    The splitter/combiner.
+ * @param ch_num	    Audio channel number.
+ * @param options	    Valid options are:
+ *			    - PJMEDIA_SPLITCOMB_AUTO_DESTROY to destroy the
+ *			      media port when the splitter is destroyed.
+ * @param port		    The media port.
+ *
+ * @return		    PJ_SUCCESS on success, or the appropriate error
+ *			    code.
+ */
+PJ_DECL(pj_status_t) pjmedia_splitcomb_set_channel(pjmedia_port *splitcomb,
+						   unsigned ch_num,
+						   unsigned options,
+						   pjmedia_port *port);
+
+/**
+ * Create a reverse phase media port for the specified channel number.
+ * For channels with reversed phase, when application calls put_frame() to
+ * the splitter/combiner, the splitter/combiner will only put the frame to
+ * a buffer. Later on, when application calls get_frame() on the channel's
+ * media port, it will return the frame that are available in the buffer.
+ * The same process happens when application calls put_frame() to the
+ * channel's media port, it will only put the frame to another buffer, which
+ * will be returned when application calls get_frame() to the splitter's 
+ * media port. So this effectively reverse the phase of the media port.
+ *
+ * @param pool		    The pool to allocate memory for the port and
+ *			    buffers.
+ * @param splitcomb	    The splitter/combiner.
+ * @param ch_num	    Audio channel number.
+ * @param options	    Valid options are:
+ *			    - PJMEDIA_SPLITCOMB_AUTO_DESTROY to destroy the
+ *			      media port when the splitter is destroyed.
+ * @param p_chport	    The media port created with reverse phase for
+ *			    the specified audio channel.
+ *
+ * @return		    PJ_SUCCESS on success, or the appropriate error
+ *			    code.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_splitcomb_create_rev_channel( pj_pool_t *pool,
+				      pjmedia_port *splitcomb,
+				      unsigned ch_num,
+				      unsigned options,
+				      pjmedia_port **p_chport);
+
+
+
+
+#endif	/* __PJMEDIA_SPLITCOMB_H__ */
+
+