--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_good/gst/law/mulaw-decode.c	Fri Apr 16 15:15:52 2010 +0300
@@ -0,0 +1,309 @@
+/* GStreamer
+ * 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.
+ */
+/**
+ * SECTION:element-mulawdec
+ *
+ * This element decodes mulaw audio. Mulaw coding is also known as G.711.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <gst/gst.h>
+#include "mulaw-decode.h"
+#include "mulaw-conversion.h"
+
+extern GstStaticPadTemplate mulaw_dec_src_factory;
+extern GstStaticPadTemplate mulaw_dec_sink_factory;
+
+/* Stereo signals and args */
+enum
+{
+  /* FILL ME */
+  LAST_SIGNAL
+};
+
+enum
+{
+  ARG_0
+};
+
+static void gst_mulawdec_class_init (GstMuLawDecClass * klass);
+static void gst_mulawdec_base_init (GstMuLawDecClass * klass);
+static void gst_mulawdec_init (GstMuLawDec * mulawdec);
+static GstStateChangeReturn
+gst_mulawdec_change_state (GstElement * element, GstStateChange transition);
+
+static GstFlowReturn gst_mulawdec_chain (GstPad * pad, GstBuffer * buffer);
+
+static GstElementClass *parent_class = NULL;
+
+static gboolean
+mulawdec_sink_setcaps (GstPad * pad, GstCaps * caps)
+{
+  GstMuLawDec *mulawdec;
+  GstStructure *structure;
+  int rate, channels;
+  gboolean ret;
+  GstCaps *outcaps;
+
+  mulawdec = GST_MULAWDEC (GST_PAD_PARENT (pad));
+
+  structure = gst_caps_get_structure (caps, 0);
+  ret = gst_structure_get_int (structure, "rate", &rate);
+  ret = ret && gst_structure_get_int (structure, "channels", &channels);
+  if (!ret)
+    return FALSE;
+
+  outcaps = gst_caps_new_simple ("audio/x-raw-int",
+      "width", G_TYPE_INT, 16,
+      "depth", G_TYPE_INT, 16,
+      "endianness", G_TYPE_INT, G_BYTE_ORDER,
+      "signed", G_TYPE_BOOLEAN, TRUE,
+      "rate", G_TYPE_INT, rate, "channels", G_TYPE_INT, channels, NULL);
+  ret = gst_pad_set_caps (mulawdec->srcpad, outcaps);
+  gst_caps_unref (outcaps);
+
+  if (ret) {
+    GST_DEBUG_OBJECT (mulawdec, "rate=%d, channels=%d", rate, channels);
+    mulawdec->rate = rate;
+    mulawdec->channels = channels;
+  }
+  return ret;
+}
+
+static GstCaps *
+mulawdec_getcaps (GstPad * pad)
+{
+  GstMuLawDec *mulawdec;
+  GstPad *otherpad;
+  GstCaps *othercaps, *result;
+  const GstCaps *templ;
+  gchar *name;
+  gint i;
+
+  mulawdec = GST_MULAWDEC (GST_PAD_PARENT (pad));
+
+  /* figure out the name of the caps we are going to return */
+  if (pad == mulawdec->srcpad) {
+    name = "audio/x-raw-int";
+    otherpad = mulawdec->sinkpad;
+  } else {
+    name = "audio/x-mulaw";
+    otherpad = mulawdec->srcpad;
+  }
+  /* get caps from the peer, this can return NULL when there is no peer */
+  othercaps = gst_pad_peer_get_caps (otherpad);
+
+  /* get the template caps to make sure we return something acceptable */
+  templ = gst_pad_get_pad_template_caps (pad);
+
+  if (othercaps) {
+    /* there was a peer */
+    othercaps = gst_caps_make_writable (othercaps);
+
+    /* go through the caps and remove the fields we don't want */
+    for (i = 0; i < gst_caps_get_size (othercaps); i++) {
+      GstStructure *structure;
+
+      structure = gst_caps_get_structure (othercaps, i);
+
+      /* adjust the name */
+      gst_structure_set_name (structure, name);
+
+      if (pad == mulawdec->sinkpad) {
+        /* remove the fields we don't want */
+        gst_structure_remove_fields (structure, "width", "depth", "endianness",
+            "signed", NULL);
+      } else {
+        /* add fixed fields */
+        gst_structure_set (structure, "width", G_TYPE_INT, 16,
+            "depth", G_TYPE_INT, 16,
+            "endianness", G_TYPE_INT, G_BYTE_ORDER,
+            "signed", G_TYPE_BOOLEAN, TRUE, NULL);
+      }
+    }
+    /* filter against the allowed caps of the pad to return our result */
+    result = gst_caps_intersect (othercaps, templ);
+    gst_caps_unref (othercaps);
+  } else {
+    /* there was no peer, return the template caps */
+    result = gst_caps_copy (templ);
+  }
+  return result;
+}
+
+GType
+gst_mulawdec_get_type (void)
+{
+  static GType mulawdec_type = 0;
+
+  if (!mulawdec_type) {
+    static const GTypeInfo mulawdec_info = {
+      sizeof (GstMuLawDecClass),
+      (GBaseInitFunc) gst_mulawdec_base_init,
+      NULL,
+      (GClassInitFunc) gst_mulawdec_class_init,
+      NULL,
+      NULL,
+      sizeof (GstMuLawDec),
+      0,
+      (GInstanceInitFunc) gst_mulawdec_init,
+    };
+
+    mulawdec_type =
+        g_type_register_static (GST_TYPE_ELEMENT, "GstMuLawDec", &mulawdec_info,
+        0);
+  }
+  return mulawdec_type;
+}
+
+static void
+gst_mulawdec_base_init (GstMuLawDecClass * klass)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+  const GstElementDetails mulawdec_details =
+      GST_ELEMENT_DETAILS ("Mu Law audio decoder",
+      "Codec/Decoder/Audio",
+      "Convert 8bit mu law to 16bit PCM",
+      "Zaheer Abbas Merali <zaheerabbas at merali dot org>");
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&mulaw_dec_src_factory));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&mulaw_dec_sink_factory));
+  gst_element_class_set_details (element_class, &mulawdec_details);
+}
+
+static void
+gst_mulawdec_class_init (GstMuLawDecClass * klass)
+{
+  GstElementClass *element_class = (GstElementClass *) klass;
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  element_class->change_state = GST_DEBUG_FUNCPTR (gst_mulawdec_change_state);
+}
+
+static void
+gst_mulawdec_init (GstMuLawDec * mulawdec)
+{
+  mulawdec->sinkpad =
+      gst_pad_new_from_static_template (&mulaw_dec_sink_factory, "sink");
+  gst_pad_set_setcaps_function (mulawdec->sinkpad, mulawdec_sink_setcaps);
+  gst_pad_set_getcaps_function (mulawdec->sinkpad, mulawdec_getcaps);
+  gst_pad_set_chain_function (mulawdec->sinkpad, gst_mulawdec_chain);
+  gst_element_add_pad (GST_ELEMENT (mulawdec), mulawdec->sinkpad);
+
+  mulawdec->srcpad =
+      gst_pad_new_from_static_template (&mulaw_dec_src_factory, "src");
+  gst_pad_use_fixed_caps (mulawdec->srcpad);
+  gst_pad_set_getcaps_function (mulawdec->srcpad, mulawdec_getcaps);
+  gst_element_add_pad (GST_ELEMENT (mulawdec), mulawdec->srcpad);
+}
+
+static GstFlowReturn
+gst_mulawdec_chain (GstPad * pad, GstBuffer * buffer)
+{
+  GstMuLawDec *mulawdec;
+  gint16 *linear_data;
+  guint8 *mulaw_data;
+  guint mulaw_size;
+  GstBuffer *outbuf;
+  GstFlowReturn ret;
+
+  mulawdec = GST_MULAWDEC (GST_PAD_PARENT (pad));
+
+  if (G_UNLIKELY (mulawdec->rate == 0))
+    goto not_negotiated;
+
+  mulaw_data = (guint8 *) GST_BUFFER_DATA (buffer);
+  mulaw_size = GST_BUFFER_SIZE (buffer);
+
+  ret =
+      gst_pad_alloc_buffer_and_set_caps (mulawdec->srcpad,
+      GST_BUFFER_OFFSET_NONE, mulaw_size * 2, GST_PAD_CAPS (mulawdec->srcpad),
+      &outbuf);
+  if (ret != GST_FLOW_OK)
+    goto alloc_failed;
+
+  linear_data = (gint16 *) GST_BUFFER_DATA (outbuf);
+
+  /* copy discont flag */
+  if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))
+    GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);
+
+  GST_BUFFER_TIMESTAMP (outbuf) = GST_BUFFER_TIMESTAMP (buffer);
+  if (GST_BUFFER_DURATION (outbuf) == GST_CLOCK_TIME_NONE)
+    GST_BUFFER_DURATION (outbuf) = gst_util_uint64_scale_int (GST_SECOND,
+        mulaw_size * 2, 2 * mulawdec->rate * mulawdec->channels);
+  else
+    GST_BUFFER_DURATION (outbuf) = GST_BUFFER_DURATION (buffer);
+  gst_buffer_set_caps (outbuf, GST_PAD_CAPS (mulawdec->srcpad));
+
+  mulaw_decode (mulaw_data, linear_data, mulaw_size);
+
+  gst_buffer_unref (buffer);
+
+  ret = gst_pad_push (mulawdec->srcpad, outbuf);
+
+  return ret;
+
+  /* ERRORS */
+not_negotiated:
+  {
+    GST_WARNING_OBJECT (mulawdec, "no input format set: not-negotiated");
+    gst_buffer_unref (buffer);
+    return GST_FLOW_NOT_NEGOTIATED;
+  }
+alloc_failed:
+  {
+    GST_DEBUG_OBJECT (mulawdec, "pad alloc failed, flow: %s",
+        gst_flow_get_name (ret));
+    gst_buffer_unref (buffer);
+    return ret;
+  }
+}
+
+static GstStateChangeReturn
+gst_mulawdec_change_state (GstElement * element, GstStateChange transition)
+{
+  GstStateChangeReturn ret;
+  GstMuLawDec *dec = GST_MULAWDEC (element);
+
+  switch (transition) {
+    default:
+      break;
+  }
+
+  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+  if (ret != GST_STATE_CHANGE_SUCCESS)
+    return ret;
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      dec->rate = 0;
+      dec->channels = 0;
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+}