added some function to support framestamps & timestamps

Original commit message from CVS:
added some function to support framestamps & timestamps

libs/audio/gstaudio.c

@@ -1,5 +1,89 @@
+/* Gnome-Streamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
 #include "gstaudio.h"
 
+int
+gst_audio_frame_byte_size (GstPad* pad)
+{
+/* calculate byte size of an audio frame
+ * this should be moved closer to the gstreamer core
+ * and be implemented for every mime type IMO
+ * returns 0 if there's an error, or the byte size if everything's ok
+ */
+
+  int width = 0;
+  int channels = 0;
+
+  GstCaps *caps = NULL;
+
+  /* get caps of pad */
+  caps = GST_PAD_CAPS (pad);
+
+  if (caps == NULL)
+    /* ERROR: could not get caps of pad */
+    return 0;
+
+  width    = gst_caps_get_int (caps, "width");
+  channels = gst_caps_get_int (caps, "channels");
+  return (width / 8) * channels; 
+}
+
+long
+gst_audio_frame_length (GstPad* pad, GstBuffer* buf)
+/* calculate length of buffer in frames
+ * this should be moved closer to the gstreamer core
+ * and be implemented for every mime type IMO
+ * returns 0 if there's an error, or the number of frames if everything's ok
+ */
+{
+  int frame_byte_size = 0;
+
+  frame_byte_size = gst_audio_frame_byte_size (pad);
+  if (frame_byte_size == 0)
+    /* error */
+    return 0;
+  /* FIXME: this function assumes the buffer size to be a whole multiple
+   *  	    of the frame byte size
+   */
+  return GST_BUFFER_SIZE (buf) / frame_byte_size;
+}
+
+long
+gst_audio_frame_rate (GstPad *pad)
+/*
+ * calculate frame rate (based on caps of pad)
+ * returns 0 if failed, rate if success
+ */
+{
+  GstCaps *caps = NULL;
+
+  /* get caps of pad */
+  caps = GST_PAD_CAPS (pad);
+
+  if (caps == NULL)
+    /* ERROR: could not get caps of pad */
+    return 0;
+  else
+    return gst_caps_get_int (caps, "rate");
+}
+
 double 
 gst_audio_length (GstPad* pad, GstBuffer* buf)
 {

libs/audio/gstaudio.h

@@ -25,7 +25,15 @@
 
 #include <gst/gst.h>
 
+/* get byte size of audio frame (based on caps of pad */
+int		gst_audio_frame_byte_size 	(GstPad* pad);
+
+/* get length in frames of buffer */
+long		gst_audio_frame_length 		(GstPad* pad, GstBuffer* buf);
+
+/* get frame rate based on caps */
+long		gst_audio_frame_rate		(GstPad *pad);
+
 /* calculate length in seconds of audio buffer buf based on caps of pad */
-
+double 		gst_audio_length 		(GstPad* pad, GstBuffer* buf);
-double 		gst_audio_length (GstPad* pad, GstBuffer* buf);