Surround sound support.

Original commit message from CVS:
* ext/a52dec/gsta52dec.c: (gst_a52dec_channels), (gst_a52dec_push),
(gst_a52dec_reneg), (gst_a52dec_loop), (plugin_init):
* ext/alsa/gstalsa.c: (gst_alsa_get_caps):
* ext/alsa/gstalsaplugin.c: (plugin_init):
* ext/dts/gstdtsdec.c: (gst_dtsdec_channels),
(gst_dtsdec_renegotiate), (gst_dtsdec_loop), (plugin_init):
* ext/faad/gstfaad.c: (gst_faad_init), (gst_faad_chanpos_from_gst),
(gst_faad_chanpos_to_gst), (gst_faad_sinkconnect),
(gst_faad_srcgetcaps), (gst_faad_srcconnect), (gst_faad_chain),
(gst_faad_change_state), (plugin_init):
* ext/faad/gstfaad.h:
* ext/vorbis/vorbis.c: (plugin_init):
* ext/vorbis/vorbisdec.c: (vorbis_dec_chain):
* gst-libs/gst/audio/Makefile.am:
* gst-libs/gst/audio/audio.c: (plugin_init):
* gst-libs/gst/audio/multichannel.c:
(gst_audio_check_channel_positions),
(gst_audio_get_channel_positions),
(gst_audio_set_channel_positions),
(gst_audio_set_structure_channel_positions_list),
(add_list_to_struct), (gst_audio_set_caps_channel_positions_list),
(gst_audio_fixate_channel_positions):
* gst-libs/gst/audio/multichannel.h:
* gst-libs/gst/audio/testchannels.c: (main):
* gst/audioconvert/gstaudioconvert.c:
(gst_audio_convert_class_init), (gst_audio_convert_init),
(gst_audio_convert_dispose), (gst_audio_convert_getcaps),
(gst_audio_convert_parse_caps), (gst_audio_convert_link),
(gst_audio_convert_fixate), (gst_audio_convert_channels):
* gst/audioconvert/plugin.c: (plugin_init):
Surround sound support.

ChangeLog

@@ -1,3 +1,37 @@
+2004-11-25  Ronald S. Bultje  <rbultje@ronald.bitfreak.net>
+
+	* ext/a52dec/gsta52dec.c: (gst_a52dec_channels), (gst_a52dec_push),
+	(gst_a52dec_reneg), (gst_a52dec_loop), (plugin_init):
+	* ext/alsa/gstalsa.c: (gst_alsa_get_caps):
+	* ext/alsa/gstalsaplugin.c: (plugin_init):
+	* ext/dts/gstdtsdec.c: (gst_dtsdec_channels),
+	(gst_dtsdec_renegotiate), (gst_dtsdec_loop), (plugin_init):
+	* ext/faad/gstfaad.c: (gst_faad_init), (gst_faad_chanpos_from_gst),
+	(gst_faad_chanpos_to_gst), (gst_faad_sinkconnect),
+	(gst_faad_srcgetcaps), (gst_faad_srcconnect), (gst_faad_chain),
+	(gst_faad_change_state), (plugin_init):
+	* ext/faad/gstfaad.h:
+	* ext/vorbis/vorbis.c: (plugin_init):
+	* ext/vorbis/vorbisdec.c: (vorbis_dec_chain):
+	* gst-libs/gst/audio/Makefile.am:
+	* gst-libs/gst/audio/audio.c: (plugin_init):
+	* gst-libs/gst/audio/multichannel.c:
+	(gst_audio_check_channel_positions),
+	(gst_audio_get_channel_positions),
+	(gst_audio_set_channel_positions),
+	(gst_audio_set_structure_channel_positions_list),
+	(add_list_to_struct), (gst_audio_set_caps_channel_positions_list),
+	(gst_audio_fixate_channel_positions):
+	* gst-libs/gst/audio/multichannel.h:
+	* gst-libs/gst/audio/testchannels.c: (main):
+	* gst/audioconvert/gstaudioconvert.c:
+	(gst_audio_convert_class_init), (gst_audio_convert_init),
+	(gst_audio_convert_dispose), (gst_audio_convert_getcaps),
+	(gst_audio_convert_parse_caps), (gst_audio_convert_link),
+	(gst_audio_convert_fixate), (gst_audio_convert_channels):
+	* gst/audioconvert/plugin.c: (plugin_init):
+	  Surround sound support.
+
 2004-11-25  Ronald S. Bultje  <rbultje@ronald.bitfreak.net>
 
 	* ext/ogg/gstoggdemux.c: (gst_ogg_demux_push):

ext/dts/gstdtsdec.c

@@ -26,6 +26,8 @@
 #include <stdlib.h>
 
 #include <gst/gst.h>
+#include <gst/audio/multichannel.h>
+
 #include <dts.h>
 
 #include "gstdtsdec.h"
@@ -180,42 +182,102 @@ gst_dtsdec_init (GstDtsDec * dtsdec)
 }
 
 static gint
-gst_dtsdec_channels (uint32_t flags)
+gst_dtsdec_channels (uint32_t flags, GstAudioChannelPosition ** pos)
 {
   gint chans = 0;
 
   switch (flags & DTS_CHANNEL_MASK) {
     case DTS_MONO:
       chans = 1;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 2);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_MONO;
+      }
       break;
-    case DTS_CHANNEL:
+      /* case DTS_CHANNEL: */
     case DTS_STEREO:
     case DTS_STEREO_SUMDIFF:
     case DTS_STEREO_TOTAL:
     case DTS_DOLBY:
       chans = 2;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 3);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+      }
       break;
     case DTS_3F:
+      chans = 3;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 4);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+      }
+      break;
     case DTS_2F1R:
       chans = 3;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 4);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_REAR_CENTER;
+      }
       break;
     case DTS_3F1R:
+      chans = 4;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 5);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        *pos[3] = GST_AUDIO_CHANNEL_POSITION_REAR_CENTER;
+      }
+      break;
     case DTS_2F2R:
       chans = 4;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 5);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_REAR_LEFT;
+        *pos[3] = GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT;
+      }
       break;
     case DTS_3F2R:
       chans = 5;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 6);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        *pos[3] = GST_AUDIO_CHANNEL_POSITION_REAR_LEFT;
+        *pos[4] = GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT;
+      }
       break;
     case DTS_4F2R:
       chans = 6;
+      if (pos) {
+        *pos = g_new (GstAudioChannelPosition, 7);
+        *pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER;
+        *pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER;
+        *pos[2] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        *pos[3] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        *pos[4] = GST_AUDIO_CHANNEL_POSITION_REAR_LEFT;
+        *pos[5] = GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT;
+      }
       break;
     default:
       /* error */
       g_warning ("dtsdec: invalid flags 0x%x", flags);
       return 0;
   }
-  if (flags & DTS_LFE)
+  if (flags & DTS_LFE) {
+    if (pos) {
+      *pos[chans] = GST_AUDIO_CHANNEL_POSITION_LFE;
+    }
     chans += 1;
+  }
 
   return chans;
 }
@@ -223,8 +285,12 @@ gst_dtsdec_channels (uint32_t flags)
 static gboolean
 gst_dtsdec_renegotiate (GstDtsDec * dts)
 {
+  GstAudioChannelPosition *pos;
   GstCaps *caps = gst_caps_from_string (DTS_CAPS);
-  gint channels = gst_dtsdec_channels (dts->using_channels);
+  gint channels = gst_dtsdec_channels (dts->using_channels, &pos);
+
+  if (!channels)
+    return FALSE;
 
   GST_INFO ("dtsdec renegotiate, channels=%d, rate=%d",
       channels, dts->sample_rate);
@@ -232,6 +298,8 @@ gst_dtsdec_renegotiate (GstDtsDec * dts)
   gst_caps_set_simple (caps,
       "channels", G_TYPE_INT, channels,
       "rate", G_TYPE_INT, (gint) dts->sample_rate, NULL);
+  gst_audio_set_channel_positions (gst_caps_get_structure (caps, 0), pos);
+  g_free (pos);
 
   return gst_pad_set_explicit_caps (dts->srcpad, caps);
 }
@@ -381,7 +449,7 @@ gst_dtsdec_loop (GstElement * element)
     }
 
     samples = dts_samples (dts->state);
-    num_c = gst_dtsdec_channels (dts->using_channels);
+    num_c = gst_dtsdec_channels (dts->using_channels, NULL);
     out = gst_buffer_new_and_alloc ((SAMPLE_WIDTH / 8) * 256 * num_c);
     GST_BUFFER_TIMESTAMP (out) = timestamp;
     GST_BUFFER_DURATION (out) = GST_SECOND * 256 / dts->sample_rate;
@@ -497,7 +565,7 @@ gst_dtsdec_get_property (GObject * object, guint prop_id, GValue * value,
 static gboolean
 plugin_init (GstPlugin * plugin)
 {
-  if (!gst_library_load ("gstbytestream"))
+  if (!gst_library_load ("gstbytestream") || !gst_library_load ("gstaudio"))
     return FALSE;
 
   if (!gst_element_register (plugin, "dtsdec", GST_RANK_PRIMARY,

ext/faad/gstfaad.c

@@ -23,6 +23,8 @@
 
 #include <string.h>
 
+#include <gst/audio/multichannel.h>
+
 #include "gstfaad.h"
 
 static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
@@ -31,35 +33,61 @@ static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
     GST_STATIC_CAPS ("audio/mpeg, " "mpegversion = (int) { 2, 4 }")
     );
 
-static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
+#define STATIC_INT_CAPS(bpp) \
+  "audio/x-raw-int, " \
+    "endianness = (int) BYTE_ORDER, " \
+    "signed = (bool) TRUE, " \
+    "width = (int) " G_STRINGIFY (bpp) ", " \
+    "depth = (int) " G_STRINGIFY (bpp) ", " \
+    "rate = (int) [ 8000, 96000 ], " \
+    "channels = (int) [ 1, 8 ]"
+
+#define STATIC_FLOAT_CAPS(bpp) \
+  "audio/x-raw-float, " \
+    "endianness = (int) BYTE_ORDER, " \
+    "depth = (int) " G_STRINGIFY (bpp) ", " \
+    "rate = (int) [ 8000, 96000 ], " \
+    "channels = (int) [ 1, 8 ]"
+
+/*
+ * All except 16-bit integer are disabled until someone fixes FAAD.
+ * FAAD allocates approximately 8*1024*2 bytes bytes, which is enough
+ * for 1 frame (1024 samples) of 6 channel (5.1) 16-bit integer 16bpp
+ * audio, but not for any other. You'll get random segfaults, crashes
+ * and even valgrind goes crazy.
+ */
+
+#define STATIC_CAPS \
+  STATIC_INT_CAPS (16)
+#if 0
+"; "
+STATIC_INT_CAPS (24)
+    "; "
+STATIC_INT_CAPS (32)
+    "; "
+STATIC_FLOAT_CAPS (32)
+    "; "
+STATIC_FLOAT_CAPS (64)
+#endif
+     static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
     GST_PAD_SRC,
     GST_PAD_ALWAYS,
-    GST_STATIC_CAPS ("audio/x-raw-int, "
+    GST_STATIC_CAPS (STATIC_CAPS)
-        "endianness = (int) BYTE_ORDER, "
-        "signed = (bool) TRUE, "
-        "width = (int) { 16, 24, 32 }, "
-        "depth = (int) { 16, 24, 32 }, "
-        "rate = (int) [ 8000, 96000 ], "
-        "channels = (int) [ 1, 6 ]; "
-        "audio/x-raw-float, "
-        "endianness = (int) BYTE_ORDER, "
-        "depth = (int) { 32, 64 }, "
-        "rate = (int) [ 8000, 96000 ], " "channels = (int) [ 1, 6 ]")
     );
 
-static void gst_faad_base_init (GstFaadClass * klass);
+     static void gst_faad_base_init (GstFaadClass * klass);
-static void gst_faad_class_init (GstFaadClass * klass);
+     static void gst_faad_class_init (GstFaadClass * klass);
-static void gst_faad_init (GstFaad * faad);
+     static void gst_faad_init (GstFaad * faad);
 
-static GstPadLinkReturn
+     static GstPadLinkReturn
-gst_faad_sinkconnect (GstPad * pad, const GstCaps * caps);
+         gst_faad_sinkconnect (GstPad * pad, const GstCaps * caps);
-static GstPadLinkReturn
+     static GstPadLinkReturn
-gst_faad_srcconnect (GstPad * pad, const GstCaps * caps);
+         gst_faad_srcconnect (GstPad * pad, const GstCaps * caps);
-static GstCaps *gst_faad_srcgetcaps (GstPad * pad);
+     static GstCaps *gst_faad_srcgetcaps (GstPad * pad);
-static void gst_faad_chain (GstPad * pad, GstData * data);
+     static void gst_faad_chain (GstPad * pad, GstData * data);
-static GstElementStateReturn gst_faad_change_state (GstElement * element);
+     static GstElementStateReturn gst_faad_change_state (GstElement * element);
 
-static GstElementClass *parent_class = NULL;
+     static GstElementClass *parent_class = NULL;
 
 /* static guint gst_faad_signals[LAST_SIGNAL] = { 0 }; */
 
@@ -123,6 +151,9 @@ gst_faad_init (GstFaad * faad)
   faad->samplerate = -1;
   faad->channels = -1;
   faad->tempbuf = NULL;
+  faad->need_channel_setup = TRUE;
+  faad->channel_positions = NULL;
+  faad->init = FALSE;
 
   GST_FLAG_SET (faad, GST_ELEMENT_EVENT_AWARE);
 
@@ -142,6 +173,102 @@ gst_faad_init (GstFaad * faad)
   gst_pad_set_getcaps_function (faad->srcpad, gst_faad_srcgetcaps);
 }
 
+/*
+ * Channel identifier conversion - caller g_free()s result!
+ */
+
+static guchar *
+gst_faad_chanpos_from_gst (GstAudioChannelPosition * pos, guint num)
+{
+  guchar *fpos = g_new (guchar, num);
+  guint n;
+
+  for (n = 0; n < num; n++) {
+    switch (pos[n]) {
+      case GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT:
+        fpos[n] = FRONT_CHANNEL_LEFT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT:
+        fpos[n] = FRONT_CHANNEL_RIGHT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER:
+        fpos[n] = FRONT_CHANNEL_CENTER;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT:
+        fpos[n] = SIDE_CHANNEL_LEFT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT:
+        fpos[n] = SIDE_CHANNEL_RIGHT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_REAR_LEFT:
+        fpos[n] = BACK_CHANNEL_LEFT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT:
+        fpos[n] = BACK_CHANNEL_RIGHT;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_REAR_CENTER:
+        fpos[n] = BACK_CHANNEL_CENTER;
+        break;
+      case GST_AUDIO_CHANNEL_POSITION_LFE:
+        fpos[n] = LFE_CHANNEL;
+        break;
+      default:
+        GST_WARNING ("Unsupported GST channel position 0x%x encountered",
+            pos[n]);
+        g_free (fpos);
+        return NULL;
+    }
+  }
+
+  return fpos;
+}
+
+static GstAudioChannelPosition *
+gst_faad_chanpos_to_gst (guchar * fpos, guint num)
+{
+  GstAudioChannelPosition *pos = g_new (GstAudioChannelPosition, num);
+  guint n;
+
+  for (n = 0; n < num; n++) {
+    switch (fpos[n]) {
+      case FRONT_CHANNEL_LEFT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+        break;
+      case FRONT_CHANNEL_RIGHT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+        break;
+      case FRONT_CHANNEL_CENTER:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER;
+        break;
+      case SIDE_CHANNEL_LEFT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT;
+        break;
+      case SIDE_CHANNEL_RIGHT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT;
+        break;
+      case BACK_CHANNEL_LEFT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_REAR_LEFT;
+        break;
+      case BACK_CHANNEL_RIGHT:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT;
+        break;
+      case BACK_CHANNEL_CENTER:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_REAR_CENTER;
+        break;
+      case LFE_CHANNEL:
+        pos[n] = GST_AUDIO_CHANNEL_POSITION_LFE;
+        break;
+      default:
+        GST_WARNING ("Unsupported FAAD channel position 0x%x encountered",
+            fpos[n]);
+        g_free (pos);
+        return NULL;
+    }
+  }
+
+  return pos;
+}
+
 static GstPadLinkReturn
 gst_faad_sinkconnect (GstPad * pad, const GstCaps * caps)
 {
@@ -160,17 +287,20 @@ gst_faad_sinkconnect (GstPad * pad, const GstCaps * caps)
             GST_BUFFER_SIZE (buf), &samplerate, &channels) < 0)
       return GST_PAD_LINK_REFUSED;
 
-    faad->samplerate = samplerate;
+    //faad->samplerate = samplerate;
-    faad->channels = channels;
+    //faad->channels = channels;
+    faad->init = TRUE;
 
     if (faad->tempbuf) {
       gst_buffer_unref (faad->tempbuf);
       faad->tempbuf = NULL;
     }
-
+  } else {
-    return GST_PAD_LINK_OK;
+    faad->init = FALSE;
   }
 
+  faad->need_channel_setup = TRUE;
+
   /* if there's no decoderspecificdata, it's all fine. We cannot know
    * much more at this point... */
   return GST_PAD_LINK_OK;
@@ -180,27 +310,45 @@ static GstCaps *
 gst_faad_srcgetcaps (GstPad * pad)
 {
   GstFaad *faad = GST_FAAD (gst_pad_get_parent (pad));
+  static GstAudioChannelPosition *supported_positions = NULL;
+  static gint num_supported_positions = LFE_CHANNEL - FRONT_CHANNEL_CENTER;
+  GstCaps *templ;
+
+  if (!supported_positions) {
+    guchar *supported_fpos = g_new0 (guchar,
+        LFE_CHANNEL - FRONT_CHANNEL_CENTER);
+    gint n;
+
+    for (n = 0; n < LFE_CHANNEL - FRONT_CHANNEL_CENTER; n++) {
+      supported_fpos[n] = n + FRONT_CHANNEL_CENTER;
+    }
+    supported_positions = gst_faad_chanpos_to_gst (supported_fpos, n);
+    g_free (supported_fpos);
+  }
 
   if (faad->handle != NULL && faad->channels != -1 && faad->samplerate != -1) {
     GstCaps *caps = gst_caps_new_empty ();
     GstStructure *str;
     gint fmt[] = {
       FAAD_FMT_16BIT,
+#if 0
       FAAD_FMT_24BIT,
       FAAD_FMT_32BIT,
       FAAD_FMT_FLOAT,
       FAAD_FMT_DOUBLE,
+#endif
       -1
     }
     , n;
 
     for (n = 0; fmt[n] != -1; n++) {
-      switch (n) {
+      switch (fmt[n]) {
         case FAAD_FMT_16BIT:
           str = gst_structure_new ("audio/x-raw-int",
               "signed", G_TYPE_BOOLEAN, TRUE,
               "width", G_TYPE_INT, 16, "depth", G_TYPE_INT, 16, NULL);
           break;
+#if 0
         case FAAD_FMT_24BIT:
           str = gst_structure_new ("audio/x-raw-int",
               "signed", G_TYPE_BOOLEAN, TRUE,
@@ -219,6 +367,7 @@ gst_faad_srcgetcaps (GstPad * pad)
           str = gst_structure_new ("audio/x-raw-float",
               "depth", G_TYPE_INT, 64, NULL);
           break;
+#endif
         default:
           str = NULL;
           break;
@@ -234,8 +383,26 @@ gst_faad_srcgetcaps (GstPad * pad)
 
       if (faad->channels != -1) {
         gst_structure_set (str, "channels", G_TYPE_INT, faad->channels, NULL);
+
+        /* put channel information here */
+        if (faad->channel_positions) {
+          GstAudioChannelPosition *pos;
+
+          pos = gst_faad_chanpos_to_gst (faad->channel_positions,
+              faad->channels);
+          if (!pos) {
+            gst_structure_free (str);
+            continue;
+          }
+          gst_audio_set_channel_positions (str, pos);
+          g_free (pos);
+        } else {
+          gst_audio_set_structure_channel_positions_list (str,
+              supported_positions, num_supported_positions);
+        }
       } else {
-        gst_structure_set (str, "channels", GST_TYPE_INT_RANGE, 1, 6, NULL);
+        gst_structure_set (str, "channels", GST_TYPE_INT_RANGE, 1, 8, NULL);
+        /* we set channel positions later */
       }
 
       gst_structure_set (str, "endianness", G_TYPE_INT, G_BYTE_ORDER, NULL);
@@ -243,10 +410,20 @@ gst_faad_srcgetcaps (GstPad * pad)
       gst_caps_append_structure (caps, str);
     }
 
+    if (faad->channels == -1) {
+      gst_audio_set_caps_channel_positions_list (caps,
+          supported_positions, num_supported_positions);
+    }
+
     return caps;
   }
 
-  return gst_caps_copy (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad)));
+  /* template with channel positions */
+  templ = gst_caps_copy (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (pad)));
+  gst_audio_set_caps_channel_positions_list (templ,
+      supported_positions, num_supported_positions);
+
+  return templ;
 }
 
 static GstPadLinkReturn
@@ -258,11 +435,13 @@ gst_faad_srcconnect (GstPad * pad, const GstCaps * caps)
   gint depth, rate, channels;
   GstFaad *faad = GST_FAAD (gst_pad_get_parent (pad));
 
-  if (!faad->handle || (faad->samplerate == -1 || faad->channels == -1)) {
+  structure = gst_caps_get_structure (caps, 0);
+
+  if (!faad->handle || (faad->samplerate == -1 || faad->channels == -1) ||
+      !faad->channel_positions) {
     return GST_PAD_LINK_DELAYED;
   }
 
-  structure = gst_caps_get_structure (caps, 0);
   mimetype = gst_structure_get_name (structure);
 
   /* Samplerate and channels are normally provided through
@@ -273,6 +452,30 @@ gst_faad_srcconnect (GstPad * pad, const GstCaps * caps)
     return GST_PAD_LINK_REFUSED;
   }
 
+  /* Another internal checkup. */
+  if (faad->need_channel_setup) {
+    GstAudioChannelPosition *pos;
+    guchar *fpos;
+    guint i;
+
+    pos = gst_audio_get_channel_positions (structure);
+    if (!pos) {
+      return GST_PAD_LINK_DELAYED;
+    }
+    fpos = gst_faad_chanpos_from_gst (pos, faad->channels);
+    g_free (pos);
+    if (!fpos)
+      return GST_PAD_LINK_REFUSED;
+
+    for (i = 0; i < faad->channels; i++) {
+      if (fpos[i] != faad->channel_positions[i]) {
+        g_free (fpos);
+        return GST_PAD_LINK_REFUSED;
+      }
+    }
+    g_free (fpos);
+  }
+
   if (!strcmp (mimetype, "audio/x-raw-int")) {
     gint width;
 
@@ -286,39 +489,47 @@ gst_faad_srcconnect (GstPad * pad, const GstCaps * caps)
       case 16:
         fmt = FAAD_FMT_16BIT;
         break;
+#if 0
       case 24:
         fmt = FAAD_FMT_24BIT;
         break;
       case 32:
         fmt = FAAD_FMT_32BIT;
         break;
+#endif
     }
   } else {
     if (!gst_structure_get_int (structure, "depth", &depth))
       return GST_PAD_LINK_REFUSED;
 
     switch (depth) {
+#if 0
       case 32:
         fmt = FAAD_FMT_FLOAT;
         break;
       case 64:
         fmt = FAAD_FMT_DOUBLE;
         break;
+#endif
     }
   }
 
   if (fmt != -1) {
     faacDecConfiguration *conf;
 
+    g_print ("Set format %d\n", fmt);
     conf = faacDecGetCurrentConfiguration (faad->handle);
     conf->outputFormat = fmt;
-    faacDecSetConfiguration (faad->handle, conf);
+    g_print ("Trying to conf\n");
+    if (faacDecSetConfiguration (faad->handle, conf) == 0)
+      return GST_PAD_LINK_REFUSED;
+    g_print ("Done\n");
     /* FIXME: handle return value, how? */
     faad->bps = depth / 8;
 
     return GST_PAD_LINK_OK;
   }
-
+  g_print ("Format not recognized\n");
   return GST_PAD_LINK_REFUSED;
 }
 
@@ -329,7 +540,7 @@ gst_faad_chain (GstPad * pad, GstData * data)
   guchar *input_data;
   GstFaad *faad = GST_FAAD (gst_pad_get_parent (pad));
   GstBuffer *buf, *outbuf;
-  faacDecFrameInfo info;
+  faacDecFrameInfo *info;
   void *out;
 
   if (GST_IS_EVENT (data)) {
@@ -338,18 +549,8 @@ gst_faad_chain (GstPad * pad, GstData * data)
     switch (GST_EVENT_TYPE (event)) {
       case GST_EVENT_EOS:
         if (faad->tempbuf != NULL) {
-          /* Try to decode the remaining data */
-          out = faacDecDecode (faad->handle, &info,
-              GST_BUFFER_DATA (faad->tempbuf), GST_BUFFER_SIZE (faad->tempbuf));
           gst_buffer_unref (faad->tempbuf);
           faad->tempbuf = NULL;
-          if (out && !info.error && info.samples > 0) {
-            outbuf = gst_buffer_new_and_alloc (info.samples * faad->bps);
-            /* ugh */
-            memcpy (GST_BUFFER_DATA (outbuf), out, GST_BUFFER_SIZE (outbuf));
-
-            gst_pad_push (faad->srcpad, GST_DATA (outbuf));
-          }
         }
         gst_element_set_eos (GST_ELEMENT (faad));
         gst_pad_push (faad->srcpad, data);
@@ -360,55 +561,89 @@ gst_faad_chain (GstPad * pad, GstData * data)
     }
   }
 
+  info = g_new0 (faacDecFrameInfo, 1);
+
+  /* buffer + remaining data */
   buf = GST_BUFFER (data);
-
-  if (faad->samplerate == -1 || faad->channels == -1) {
-    GstPadLinkReturn ret;
-    gulong samplerate;
-    guchar channels;
-
-    faacDecInit (faad->handle,
-        GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf), &samplerate, &channels);
-    faad->samplerate = samplerate;
-    faad->channels = channels;
-
-    ret = gst_pad_renegotiate (faad->srcpad);
-    if (GST_PAD_LINK_FAILED (ret)) {
-      GST_ELEMENT_ERROR (faad, CORE, NEGOTIATION, (NULL), (NULL));
-      gst_buffer_unref (buf);
-      return;
-    }
-  }
-
-  /* Use the leftovers */
   if (faad->tempbuf) {
     buf = gst_buffer_join (faad->tempbuf, buf);
     faad->tempbuf = NULL;
   }
 
+  /* init if not already done during capsnego */
+  if (!faad->init) {
+    gulong samplerate;
+    guchar channels;
+
+    faacDecInit (faad->handle,
+        GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf), &samplerate, &channels);
+    faad->init = TRUE;
+
+    /* store for renegotiation later on */
+    info->samplerate = samplerate;
+    info->channels = channels;
+  } else {
+    info->samplerate = 0;
+    info->channels = 0;
+  }
+
+  /* decode cycle */
   input_data = GST_BUFFER_DATA (buf);
   input_size = GST_BUFFER_SIZE (buf);
-  info.bytesconsumed = input_size;
+  info->bytesconsumed = input_size;
-  while (input_size > (faad->channels * FAAD_MIN_STREAMSIZE)
+  while (input_size >= FAAD_MIN_STREAMSIZE && info->bytesconsumed > 0) {
-      && info.bytesconsumed > 0) {
+    g_print ("Decoding %d bytes of data\n", input_size);
-    out = faacDecDecode (faad->handle, &info, input_data, input_size);
+    out = faacDecDecode (faad->handle, info, input_data, input_size);
-    if (info.error) {
+    g_print ("done, rec. %p\n", out);
+    if (info->error) {
       GST_ELEMENT_ERROR (faad, STREAM, DECODE, (NULL),
-          ("Failed to decode buffer: %s", faacDecGetErrorMessage (info.error)));
+          ("Failed to decode buffer: %s",
+              faacDecGetErrorMessage (info->error)));
       break;
     }
 
-    input_size -= info.bytesconsumed;
+    if (info->bytesconsumed > input_size)
-    input_data += info.bytesconsumed;
+      info->bytesconsumed = input_size;
+    input_size -= info->bytesconsumed;
+    input_data += info->bytesconsumed;
 
-    if (out) {
+    if (out && info->samples > 0) {
+      gboolean fmt_change = FALSE;
 
-      if (info.samplerate != faad->samplerate
+      /* see if we need to renegotiate */
-          || info.channels != faad->channels) {
+      if (info->samplerate != faad->samplerate ||
+          info->channels != faad->channels || !faad->channel_positions) {
+        fmt_change = TRUE;
+      } else {
+        gint i;
+
+        for (i = 0; i < info->channels; i++) {
+          if (info->channel_position[i] != faad->channel_positions[i])
+            fmt_change = TRUE;
+        }
+      }
+
+      if (fmt_change) {
         GstPadLinkReturn ret;
 
-        faad->samplerate = info.samplerate;
+        g_print ("Format change\n");
-        faad->channels = info.channels;
+        g_print ("To %ld Hz, %d chans, %d/%d/%d/%d/%d/%d\n",
+            info->samplerate, info->channels,
+            info->channel_position[0],
+            info->channel_position[1],
+            info->channel_position[2],
+            info->channel_position[3],
+            info->channel_position[4], info->channel_position[5]);
+        /* store new negotiation information */
+        faad->samplerate = info->samplerate;
+        faad->channels = info->channels;
+        if (faad->channel_positions)
+          g_free (faad->channel_positions);
+        faad->channel_positions = g_new (guint8, faad->channels);
+        memcpy (faad->channel_positions, info->channel_position,
+            faad->channels);
+
+        /* and negotiate */
         ret = gst_pad_renegotiate (faad->srcpad);
         if (GST_PAD_LINK_FAILED (ret)) {
           GST_ELEMENT_ERROR (faad, CORE, NEGOTIATION, (NULL), (NULL));
@@ -416,30 +651,35 @@ gst_faad_chain (GstPad * pad, GstData * data)
         }
       }
 
-      if (info.samples > 0) {
+      /* play decoded data */
-        outbuf = gst_buffer_new_and_alloc (info.samples * faad->bps);
+      if (info->samples > 0) {
+        g_print ("Playing %ld samples from buf %p\n", info->samples, out);
+        outbuf = gst_buffer_new_and_alloc (info->samples * faad->bps);
         /* ugh */
         memcpy (GST_BUFFER_DATA (outbuf), out, GST_BUFFER_SIZE (outbuf));
+        g_print ("done, to %p\n", GST_BUFFER_DATA (outbuf));
         GST_BUFFER_TIMESTAMP (outbuf) = GST_BUFFER_TIMESTAMP (buf);
         GST_BUFFER_DURATION (outbuf) = GST_BUFFER_DURATION (buf);
 
         gst_pad_push (faad->srcpad, GST_DATA (outbuf));
       }
     }
-  };
+  }
 
   /* Keep the leftovers */
   if (input_size > 0) {
-    if (input_size < GST_BUFFER_SIZE (buf))
+    if (input_size < GST_BUFFER_SIZE (buf)) {
       faad->tempbuf = gst_buffer_create_sub (buf,
           GST_BUFFER_SIZE (buf) - input_size, input_size);
-    else {
+    } else {
       faad->tempbuf = buf;
       gst_buffer_ref (buf);
     }
   }
 
   gst_buffer_unref (buf);
+
+  g_free (info);
 }
 
 static GstElementStateReturn
@@ -463,6 +703,10 @@ gst_faad_change_state (GstElement * element)
     case GST_STATE_PAUSED_TO_READY:
       faad->samplerate = -1;
       faad->channels = -1;
+      faad->need_channel_setup = TRUE;
+      faad->init = FALSE;
+      g_free (faad->channel_positions);
+      faad->channel_positions = NULL;
       break;
     case GST_STATE_READY_TO_NULL:
       faacDecClose (faad->handle);
@@ -485,7 +729,8 @@ gst_faad_change_state (GstElement * element)
 static gboolean
 plugin_init (GstPlugin * plugin)
 {
-  return gst_element_register (plugin, "faad", GST_RANK_PRIMARY, GST_TYPE_FAAD);
+  return gst_library_load ("gstaudio") &&
+      gst_element_register (plugin, "faad", GST_RANK_PRIMARY, GST_TYPE_FAAD);
 }
 
 GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,

ext/faad/gstfaad.h

@@ -52,6 +52,11 @@ typedef struct _GstFaad {
 
   /* FAAD object */
   faacDecHandle handle;
+  gboolean init;
+
+  /* FAAD channel setup */
+  guchar *channel_positions;
+  gboolean need_channel_setup;
 } GstFaad;
 
 typedef struct _GstFaadClass {

gst-libs/gst/audio/Makefile.am

@@ -1,15 +1,32 @@
+# variables used for enum/marshal generation
+glib_enum_headers=multichannel.h
+glib_enum_define=GST_AUDIO
+glib_enum_prefix=gst_audio
+
+built_sources = multichannel-enumtypes.c
+built_headers = multichannel-enumtypes.h
+BUILT_SOURCES = $(built_sources) $(built_headers)
+
 librarydir = $(libdir)/gstreamer-@GST_MAJORMINOR@
 
 library_LTLIBRARIES = libgstaudio.la libgstaudiofilter.la
 noinst_LTLIBRARIES = libgstaudiofilterexample.la
 
 EXTRA_DIST = gstaudiofiltertemplate.c make_filter
-CLEANFILES = gstaudiofilterexample.c
+CLEANFILES = gstaudiofilterexample.c \
+	$(BUILT_SOURCES)
 
-libgstaudio_la_SOURCES = audio.c audioclock.c
+libgstaudio_la_SOURCES = audio.c audioclock.c \
+	multichannel.c
+nodist_libgstaudio_la_SOURCES = $(built_sources)
 
 libgstaudioincludedir = $(includedir)/gstreamer-@GST_MAJORMINOR@/gst/audio
-libgstaudioinclude_HEADERS = audio.h audioclock.h gstaudiofilter.h
+libgstaudioinclude_HEADERS = \
+	audio.h \
+	audioclock.h \
+	gstaudiofilter.h \
+	multichannel.h \
+	multichannel-enumtypes.h
 
 libgstaudio_la_LIBADD =
 libgstaudio_la_CFLAGS = $(GST_CFLAGS)
@@ -25,3 +42,10 @@ libgstaudiofilterexample_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
 
 gstaudiofilterexample.c: $(srcdir)/make_filter $(srcdir)/gstaudiofiltertemplate.c
 	$(srcdir)/make_filter AudiofilterExample $(srcdir)/gstaudiofiltertemplate.c
+
+noinst_PROGRAMS = testchannels
+testchannels_SOURCES = testchannels.c
+testchannels_CFLAGS = $(GST_CFLAGS)
+testchannels_LDFLAGS = $(GST_LIBS)
+
+include $(top_srcdir)/common/glib-gen.mak

gst-libs/gst/audio/audio.c

@@ -22,6 +22,7 @@
 #endif
 
 #include "audio.h"
+#include "multichannel-enumtypes.h"
 
 #include <gst/gststructure.h>
 
@@ -267,6 +268,8 @@ gst_audio_structure_set_int (GstStructure * structure, GstAudioFieldFlag flag)
 static gboolean
 plugin_init (GstPlugin * plugin)
 {
+  gst_audio_channel_position_get_type ();
+
   return TRUE;
 }
 

gst-libs/gst/audio/multichannel.c

@@ -0,0 +1,634 @@
+/* GStreamer Multichannel-Audio helper functions
+ * (c) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "multichannel.h"
+
+#define GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME "channel-positions"
+
+/*
+ * This function checks if basic assumptions apply:
+ *  - does each position occur at most once?
+ *  - do conflicting positions occur?
+ *     + front_mono vs. front_left/right
+ *     + front_center vs. front_left/right_of_center
+ *     + rear_center vs. rear_left/right
+ * It also adds some hacks that 0.8.x needs for compatibility:
+ *  - if channels == 1, are we really mono?
+ *  - if channels == 2, are we really stereo?
+ */
+
+static gboolean
+gst_audio_check_channel_positions (const GstAudioChannelPosition * pos,
+    gint channels)
+{
+  gint i, n;
+  struct
+  {
+    GstAudioChannelPosition pos1[2];
+    GstAudioChannelPosition pos2[1];
+  } conf[] = {
+    /* front: mono <-> stereo */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
+            GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT}, {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_MONO}},
+        /* front center: 2 <-> 1 */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
+            GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER}, {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER}},
+        /* rear: 2 <-> 1 */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
+            GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT}, {
+    GST_AUDIO_CHANNEL_POSITION_REAR_CENTER}}, { {
+    GST_AUDIO_CHANNEL_POSITION_INVALID}}
+  };
+
+  /* check for invalid channel positions */
+  for (n = 0; n < channels; n++) {
+    if (pos[n] == GST_AUDIO_CHANNEL_POSITION_INVALID) {
+      g_warning ("Position %d is invalid, not allowed", n);
+      return FALSE;
+    }
+  }
+
+  /* check for multiple position occurrences */
+  for (i = GST_AUDIO_CHANNEL_POSITION_INVALID + 1;
+      i < GST_AUDIO_CHANNEL_POSITION_NUM; i++) {
+    gint count = 0;
+
+    for (n = 0; n < channels; n++) {
+      if (pos[n] == i)
+        count++;
+    }
+
+    if (count > 1) {
+      g_warning ("Channel position %d occurred %d times, not allowed",
+          i, count);
+      return FALSE;
+    }
+  }
+
+  /* check for position conflicts */
+  for (i = 0; conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID; i++) {
+    gboolean found1 = FALSE, found2 = FALSE;
+
+    for (n = 0; n < channels; n++) {
+      if (pos[n] == conf[i].pos1[0] || pos[n] == conf[i].pos1[1])
+        found1 = TRUE;
+      else if (pos[n] == conf[i].pos2[0])
+        found2 = TRUE;
+    }
+
+    if (found1 && found2) {
+      g_warning ("Found conflicting channel positions %d/%d and %d",
+          conf[i].pos1[0], conf[i].pos1[1], conf[i].pos2[0]);
+      return FALSE;
+    }
+  }
+
+  /* 0.8.x evilry */
+  if ((channels == 1 && pos[0] != GST_AUDIO_CHANNEL_POSITION_FRONT_MONO) ||
+      (channels == 2 && (pos[0] != GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT ||
+              pos[1] != GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT))) {
+    g_warning ("0.8.x: channels=1 implies mono; channels=2 implies stereo");
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
+/**
+ * gst_audio_get_channel_positions:
+ * @str: A #GstStructure to retrieve channel positions from.
+ *
+ * Retrieves a number of (fixed!) audio channel positions from
+ * the provided #GstStructure and returns it as a newly allocated
+ * array. The caller should g_free () this array. The caller
+ * should also check that the members in this #GstStructure are
+ * indeed "fixed" before calling this function.
+ *
+ * Returns: a newly allocated array containing the channel
+ * positions as provided in the given #GstStructure. Returns
+ * NULL on error.
+ */
+
+GstAudioChannelPosition *
+gst_audio_get_channel_positions (GstStructure * str)
+{
+  GstAudioChannelPosition *pos;
+  gint channels, n;
+  const GValue *pos_val_arr, *pos_val_entry;
+  gboolean res;
+  GType t;
+
+  /* get number of channels, general type checkups */
+  g_return_val_if_fail (str != NULL, NULL);
+  res = gst_structure_get_int (str, "channels", &channels);
+  g_return_val_if_fail (res, NULL);
+  g_return_val_if_fail (channels > 0, NULL);
+  pos_val_arr = gst_structure_get_value (str,
+      GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME);
+
+  /* The following checks are here to retain compatibility for plugins not
+   * implementing this property. They expect that channels=1 implies mono
+   * and channels=2 implies stereo, so we follow that.
+   * This might be removed during 0.9.x. */
+  if (!pos_val_arr && (channels == 1 || channels == 2)) {
+    pos = g_new (GstAudioChannelPosition, channels);
+    if (channels == 1) {
+      pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_MONO;
+    } else {
+      pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+      pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+    }
+    return pos;
+  }
+  g_return_val_if_fail (pos_val_arr != NULL, NULL);
+  g_return_val_if_fail (gst_value_list_get_size (pos_val_arr) == channels,
+      NULL);
+  for (n = 0; n < channels; n++) {
+    t = G_VALUE_TYPE (gst_value_list_get_value (pos_val_arr, n));
+    g_return_val_if_fail (t == GST_TYPE_AUDIO_CHANNEL_POSITION, NULL);
+  }
+
+  /* ... and fill array */
+  pos = g_new (GstAudioChannelPosition, channels);
+  for (n = 0; n < channels; n++) {
+    pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
+    pos[n] = g_value_get_enum (pos_val_entry);
+  }
+
+  if (!gst_audio_check_channel_positions (pos, channels)) {
+    g_free (pos);
+    return NULL;
+  }
+
+  return pos;
+}
+
+/**
+ * gst_audio_set_channel_positions:
+ * @str: A #GstStructure to retrieve channel positions from.
+ * @pos: an array of channel positions. The number of members
+ *       in this array should be equal to the (fixed!) number
+ *       of the "channels" property in the given #GstStructure.
+ *
+ * Adds a "channel-positions" property to the given #GstStructure,
+ * which will represent the channel positions as given in the
+ * provided #GstAudioChannelPosition array.
+ */
+
+void
+gst_audio_set_channel_positions (GstStructure * str,
+    const GstAudioChannelPosition * pos)
+{
+  GValue pos_val_arr = { 0 }, pos_val_entry = {
+  0};
+  gint channels, n;
+  gboolean res;
+
+  /* get number of channels, checkups */
+  g_return_if_fail (str != NULL);
+  g_return_if_fail (pos != NULL);
+  res = gst_structure_get_int (str, "channels", &channels);
+  g_return_if_fail (res);
+  g_return_if_fail (channels > 0);
+  if (!gst_audio_check_channel_positions (pos, channels))
+    return;
+
+  /* build gvaluearray from positions */
+  g_value_init (&pos_val_entry, GST_TYPE_AUDIO_CHANNEL_POSITION);
+  g_value_init (&pos_val_arr, GST_TYPE_FIXED_LIST);
+  for (n = 0; n < channels; n++) {
+    g_value_set_enum (&pos_val_entry, pos[n]);
+    gst_value_list_append_value (&pos_val_arr, &pos_val_entry);
+  }
+  g_value_unset (&pos_val_entry);
+
+  /* add to structure */
+  gst_structure_set_value (str,
+      GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME, &pos_val_arr);
+  g_value_unset (&pos_val_arr);
+}
+
+/**
+ * gst_audio_set_structure_channel_positions_list:
+ * @str: #GstStructure to set the list of channel positions
+ *       on.
+ * @pos: the array containing one or more possible audio
+ *       channel positions that we should add in each value
+ *       of the array in the given structure.
+ * @num_positions: the number of values in pos.
+ *
+ * Sets a (possibly non-fixed) list of possible audio channel
+ * positions (given in pos) on the given structure. The
+ * structure, after this function has been called, will contain
+ * a "channel-positions" property with an array of the size of
+ * the "channels" property value in the given structure (note
+ * that this means that the channels property in the provided
+ * structure should be fixed!). Each value in the array will
+ * contain each of the values given in the pos array.
+ */
+
+void
+gst_audio_set_structure_channel_positions_list (GstStructure * str,
+    const GstAudioChannelPosition * pos, gint num_positions)
+{
+  gint channels, n, c;
+  GValue pos_val_arr = { 0 }, pos_val_list = {
+  0}, pos_val_entry = {
+  0};
+  gboolean res;
+
+  /* get number of channels, general type checkups */
+  g_return_if_fail (str != NULL);
+  g_return_if_fail (num_positions > 0);
+  g_return_if_fail (pos != NULL);
+  res = gst_structure_get_int (str, "channels", &channels);
+  g_return_if_fail (res);
+  g_return_if_fail (channels > 0);
+
+  /* 0.8.x: channels=1 or channels=2 is mono/stereo, no positions needed
+   * there (we discard them anyway) */
+  if (channels == 1 || channels == 2)
+    return;
+
+  /* create the array of lists */
+  g_value_init (&pos_val_arr, GST_TYPE_FIXED_LIST);
+  g_value_init (&pos_val_entry, GST_TYPE_AUDIO_CHANNEL_POSITION);
+  for (n = 0; n < channels; n++) {
+    g_value_init (&pos_val_list, GST_TYPE_LIST);
+    for (c = 0; c < num_positions; c++) {
+      g_value_set_enum (&pos_val_entry, pos[c]);
+      gst_value_list_append_value (&pos_val_list, &pos_val_entry);
+    }
+    gst_value_list_append_value (&pos_val_arr, &pos_val_list);
+    g_value_unset (&pos_val_list);
+  }
+  g_value_unset (&pos_val_entry);
+  gst_structure_set_value (str, GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME,
+      &pos_val_arr);
+  g_value_unset (&pos_val_arr);
+}
+
+/*
+ * Helper function for below. The structure will be conserved,
+ * but might be cut down. Any additional structures that were
+ * created will be stored in the returned caps.
+ */
+
+static GstCaps *
+add_list_to_struct (GstStructure * str,
+    const GstAudioChannelPosition * pos, gint num_positions)
+{
+  GstCaps *caps = gst_caps_new_empty ();
+  const GValue *chan_val;
+
+  chan_val = gst_structure_get_value (str, "channels");
+  if (G_VALUE_TYPE (chan_val) == G_TYPE_INT) {
+    gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
+  } else if (G_VALUE_TYPE (chan_val) == GST_TYPE_LIST) {
+    gint size;
+    const GValue *sub_val;
+
+    size = gst_value_list_get_size (chan_val);
+    sub_val = gst_value_list_get_value (chan_val, 0);
+    gst_structure_set_value (str, "channels", sub_val);
+    gst_caps_append (caps, add_list_to_struct (str, pos, num_positions));
+    while (--size > 0) {
+      str = gst_structure_copy (str);
+      sub_val = gst_value_list_get_value (chan_val, size);
+      gst_structure_set_value (str, "channels", sub_val);
+      gst_caps_append (caps, add_list_to_struct (str, pos, num_positions));
+      gst_caps_append_structure (caps, str);
+    }
+  } else if (G_VALUE_TYPE (chan_val) == GST_TYPE_INT_RANGE) {
+    gint min, max;
+
+    min = gst_value_get_int_range_min (chan_val);
+    max = gst_value_get_int_range_max (chan_val);
+
+    gst_structure_set (str, "channels", G_TYPE_INT, min, NULL);
+    gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
+    for (++min; min < max; min++) {
+      str = gst_structure_copy (str);
+      gst_structure_set (str, "channels", G_TYPE_INT, min, NULL);
+      gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
+      gst_caps_append_structure (caps, str);
+    }
+  } else {
+    g_warning ("Unknown value type for channels property");
+  }
+
+  return caps;
+}
+
+/**
+ * gst_audio_set_caps_channel_positions_list:
+ * @caps: #GstCaps to set the list of channel positions on.
+ * @pos: the array containing one or more possible audio
+ *       channel positions that we should add in each value
+ *       of the array in the given structure.
+ * @num_positions: the number of values in pos.
+ *
+ * Sets a (possibly non-fixed) list of possible audio channel
+ * positions (given in pos) on the given caps. Each of the
+ * structures of the caps, after this function has been called,
+ * will contain a "channel-positions" property with an array.
+ * Each value in the array will contain each of the values given
+ * in the pos array. Note that the size of the caps might be
+ * increased by this, since each structure with a "channel-
+ * positions" property needs to have a fixed "channels" property.
+ * The input caps is not required to have this.
+ */
+
+void
+gst_audio_set_caps_channel_positions_list (GstCaps * caps,
+    const GstAudioChannelPosition * pos, gint num_positions)
+{
+  gint size, n;
+
+  /* get number of channels, general type checkups */
+  g_return_if_fail (caps != NULL);
+  g_return_if_fail (num_positions > 0);
+  g_return_if_fail (pos != NULL);
+
+  size = gst_caps_get_size (caps);
+  for (n = 0; n < size; n++) {
+    gst_caps_append (caps, add_list_to_struct (gst_caps_get_structure (caps,
+                n), pos, num_positions));
+  }
+}
+
+/**
+ * gst_audio_fixate_channel_positions:
+ * @str: a #GstStructure containing a (possibly unfixed)
+ *       "channel-positions" property.
+ *
+ * Custom fixate function. Elements that implement some sort of
+ * channel conversion algorhithm should use this function for
+ * fixating on GstAudioChannelPosition properties. It will take
+ * care of equal channel positioning (left/right). Caller g_free()s
+ * the return value. The input properties may be (and are supposed
+ * to be) unfixed.
+ * Note that this function is mostly a hack because we currently
+ * have no way to add default fixation functions for new GTypes.
+ *
+ * Returns: fixed values that the caller could use as a fixed
+ * set of #GstAudioChannelPosition values.
+ */
+
+GstAudioChannelPosition *
+gst_audio_fixate_channel_positions (GstStructure * str)
+{
+  GstAudioChannelPosition *pos;
+  gint channels, n, num_unfixed = 0, i, c;
+  const GValue *pos_val_arr, *pos_val_entry, *pos_val;
+  gboolean res, is_stereo = TRUE;
+  GType t;
+
+  /*
+   * We're going to do this cluelessly. We'll make an array of values that
+   * conflict with each other and, for each iteration in this array, pick
+   * either one until all unknown values are filled. This might not work in
+   * corner cases but should work OK for the general case.
+   */
+  struct
+  {
+    GstAudioChannelPosition pos1[2];
+    GstAudioChannelPosition pos2[1];
+  } conf[] = {
+    /* front: mono <-> stereo */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
+            GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT}, {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_MONO}},
+        /* front center: 2 <-> 1 */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
+            GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER}, {
+    GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER}},
+        /* rear: 2 <-> 1 */
+    { {
+    GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
+            GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT}, {
+    GST_AUDIO_CHANNEL_POSITION_REAR_CENTER}}, { {
+    GST_AUDIO_CHANNEL_POSITION_INVALID, GST_AUDIO_CHANNEL_POSITION_INVALID}, {
+    GST_AUDIO_CHANNEL_POSITION_LFE}}, { {
+    GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
+            GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT}, {
+    GST_AUDIO_CHANNEL_POSITION_INVALID}}, { {
+    GST_AUDIO_CHANNEL_POSITION_INVALID, GST_AUDIO_CHANNEL_POSITION_INVALID}, {
+    GST_AUDIO_CHANNEL_POSITION_INVALID}}
+  };
+  struct
+  {
+    gint num_opt[3];
+    guint num_opts[3];
+    gboolean is_fixed[3];
+    gint choice;                /* -1 is none, 0 is the two, 1 is the one */
+  } opt;
+
+  /* get number of channels, general type checkups */
+  g_return_val_if_fail (str != NULL, NULL);
+  res = gst_structure_get_int (str, "channels", &channels);
+  g_return_val_if_fail (res, NULL);
+  g_return_val_if_fail (channels > 0, NULL);
+
+  /* 0.8.x mono/stereo checks */
+  pos_val_arr = gst_structure_get_value (str,
+      GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME);
+  if (!pos_val_arr && (channels == 1 || channels == 2)) {
+    pos = g_new (GstAudioChannelPosition, channels);
+    if (channels == 1) {
+      pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_MONO;
+    } else {
+      pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
+      pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
+    }
+    return pos;
+  }
+  g_return_val_if_fail (pos_val_arr != NULL, NULL);
+  g_return_val_if_fail (gst_value_list_get_size (pos_val_arr) == channels,
+      NULL);
+  for (n = 0; n < channels; n++) {
+    t = G_VALUE_TYPE (gst_value_list_get_value (pos_val_arr, n));
+    g_return_val_if_fail (t == GST_TYPE_LIST ||
+        t == GST_TYPE_AUDIO_CHANNEL_POSITION, NULL);
+  }
+
+  /* all unknown, to start with */
+  pos = g_new (GstAudioChannelPosition, channels);
+  for (n = 0; n < channels; n++)
+    pos[n] = GST_AUDIO_CHANNEL_POSITION_INVALID;
+  num_unfixed = channels;
+
+  /* Iterate the array of conflicting values */
+  for (i = 0; conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID ||
+      conf[i].pos2[0] != GST_AUDIO_CHANNEL_POSITION_INVALID; i++) {
+    /* front/center only important if not mono (obviously) */
+    if (conf[i].pos1[0] == GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER &&
+        !is_stereo)
+      continue;
+
+    /* init values */
+    for (n = 0; n < 3; n++) {
+      opt.num_opt[n] = -1;
+      opt.num_opts[n] = -1;
+      opt.is_fixed[n] = FALSE;
+    }
+
+    /* Now, we'll see for each channel if it allows for any of the values in
+     * the set of conflicting audio channel positions and keep scores. */
+    for (n = 0; n < channels; n++) {
+      /* if the channel is already taken, don't bother */
+      if (pos[n] != GST_AUDIO_CHANNEL_POSITION_INVALID)
+        continue;
+
+      pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
+      t = G_VALUE_TYPE (pos_val_entry);
+      if (t == GST_TYPE_LIST) {
+        /* This algorhythm is suboptimal. */
+        for (c = 0; c < gst_value_list_get_size (pos_val_entry); c++) {
+          pos_val = gst_value_list_get_value (pos_val_entry, c);
+          if (g_value_get_enum (pos_val) == conf[i].pos1[0] &&
+              opt.num_opts[0] > gst_value_list_get_size (pos_val_entry) &&
+              !opt.is_fixed[0]) {
+            /* Now test if the old position of num_opt[0] also allows for
+             * the other channel (which was skipped previously). If so,
+             * keep score. */
+            if (opt.num_opt[0] != -1) {
+              gint c1;
+
+              pos_val_entry = gst_value_list_get_value (pos_val_arr,
+                  opt.num_opt[0]);
+              if (G_VALUE_TYPE (pos_val_entry) == GST_TYPE_LIST) {
+                for (c1 = 0; c1 < gst_value_list_get_size (pos_val_entry); c1++) {
+                  pos_val = gst_value_list_get_value (pos_val_entry, c1);
+                  if (g_value_get_enum (pos_val) == conf[i].pos1[1] &&
+                      opt.num_opts[1] > opt.num_opts[0] && !opt.is_fixed[1]) {
+                    opt.num_opts[1] = opt.num_opts[0];
+                    opt.num_opt[1] = opt.num_opt[0];
+                  }
+                }
+                pos_val = gst_value_list_get_value (pos_val_entry, c);
+              }
+              pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
+            }
+
+            /* and save values */
+            opt.num_opts[0] = gst_value_list_get_size (pos_val_entry);
+            opt.num_opt[0] = n;
+          } else if (g_value_get_enum (pos_val) == conf[i].pos1[1] &&
+              opt.num_opts[1] > gst_value_list_get_size (pos_val_entry) &&
+              !opt.is_fixed[1] && n != opt.num_opt[0]) {
+            opt.num_opts[1] = gst_value_list_get_size (pos_val_entry);
+            opt.num_opt[1] = n;
+          }
+
+          /* 2 goes separately, because 0/1 vs. 2 are separate */
+          if (g_value_get_enum (pos_val) == conf[i].pos2[0] &&
+              opt.num_opts[2] > gst_value_list_get_size (pos_val_entry) &&
+              !opt.is_fixed[2]) {
+            opt.num_opts[2] = gst_value_list_get_size (pos_val_entry);
+            opt.num_opt[2] = n;
+          }
+        }
+      } else {
+        if (g_value_get_enum (pos_val_entry) == conf[i].pos1[0]) {
+          opt.num_opt[0] = n;
+          opt.is_fixed[0] = TRUE;
+        } else if (g_value_get_enum (pos_val_entry) == conf[i].pos1[1]) {
+          opt.num_opt[1] = n;
+          opt.is_fixed[1] = TRUE;
+        } else if (g_value_get_enum (pos_val_entry) == conf[i].pos2[0]) {
+          opt.num_opt[2] = n;
+          opt.is_fixed[2] = TRUE;
+        }
+      }
+    }
+
+    /* check our results and choose either one */
+    if ((opt.is_fixed[0] || opt.is_fixed[1]) && opt.is_fixed[2]) {
+      g_warning ("Pre-fixated on both %d/%d and %d - conflict!",
+          conf[i].pos1[0], conf[i].pos1[1], conf[i].pos2[0]);
+      g_free (pos);
+      return NULL;
+    } else if ((opt.is_fixed[0] && opt.num_opt[1] == -1) ||
+        (opt.is_fixed[1] && opt.num_opt[0] == -1)) {
+      g_warning ("Pre-fixated one side, but other side n/a of %d/%d",
+          conf[i].pos1[0], conf[i].pos1[1]);
+      g_free (pos);
+      return NULL;
+    } else if (opt.is_fixed[0] || opt.is_fixed[1]) {
+      opt.choice = 0;
+    } else if (opt.is_fixed[2]) {
+      opt.choice = 1;
+    } else if (opt.num_opt[0] != -1 && opt.num_opt[1] != -1) {
+      opt.choice = 0;
+    } else if (opt.num_opt[2] != -1) {
+      opt.choice = 1;
+    } else {
+      opt.choice = -1;
+    }
+
+    /* stereo? Note that we keep is_stereo to TRUE if we didn't decide on
+     * any arrangement. The mono/stereo channels might be handled elsewhere
+     * which is clearly outside the scope of this element, so we cannot
+     * know and expect the application to handle that then. */
+    if (conf[i].pos2[0] == GST_AUDIO_CHANNEL_POSITION_FRONT_MONO &&
+        opt.choice == 1) {
+      is_stereo = FALSE;
+    }
+
+    /* now actually decide what we'll do and fixate on that */
+    if (opt.choice == 0) {
+      g_assert (conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID &&
+          conf[i].pos1[1] != GST_AUDIO_CHANNEL_POSITION_INVALID);
+      pos[opt.num_opt[0]] = conf[i].pos1[0];
+      pos[opt.num_opt[1]] = conf[i].pos1[1];
+      num_unfixed -= 2;
+    } else if (opt.choice == 1) {
+      g_assert (conf[i].pos2[0] != GST_AUDIO_CHANNEL_POSITION_INVALID);
+      pos[opt.num_opt[2]] = conf[i].pos2[0];
+      num_unfixed--;
+    }
+  }
+
+  /* safety check */
+  if (num_unfixed > 0) {
+    g_warning ("%d unfixed channel positions left after fixation!",
+        num_unfixed);
+    g_free (pos);
+    return NULL;
+  }
+
+  if (!gst_audio_check_channel_positions (pos, channels)) {
+    g_free (pos);
+    return NULL;
+  }
+
+  return pos;
+}

gst-libs/gst/audio/multichannel.h

@@ -0,0 +1,86 @@
+/* GStreamer Multichannel-Audio helper functions
+ * (c) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ *
+ * 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.
+ */
+
+#ifndef __GST_AUDIO_MULTICHANNEL_H__
+#define __GST_AUDIO_MULTICHANNEL_H__
+
+#include <gst/audio/audio.h>
+#include <gst/audio/multichannel-enumtypes.h>
+
+typedef enum {
+  GST_AUDIO_CHANNEL_POSITION_INVALID = -1,
+
+  /* Main front speakers. Mono and left/right are mututally exclusive! */
+  GST_AUDIO_CHANNEL_POSITION_FRONT_MONO,
+  GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
+  GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,
+
+  /* rear. Left/right and center are mututally exclusive! */
+  GST_AUDIO_CHANNEL_POSITION_REAR_CENTER,
+  GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
+  GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT,
+
+  /* subwoofer/low-frequency */
+  GST_AUDIO_CHANNEL_POSITION_LFE,
+
+  /* Center front speakers. Center and left/right_of_center cannot be
+   * used together! */
+  GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,
+  GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
+  GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER,
+
+  /* sides */
+  GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
+  GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT,
+
+  /* don't use - counter */
+  GST_AUDIO_CHANNEL_POSITION_NUM
+} GstAudioChannelPosition;
+
+/* Retrieves or sets the positions from/to a GstStructure. Only
+ * works with fixed caps, caller should check for that! Caller
+ * g_free()s result of the getter. */
+GstAudioChannelPosition *
+	gst_audio_get_channel_positions	(GstStructure *str);
+void	gst_audio_set_channel_positions	(GstStructure *str,
+					 const GstAudioChannelPosition *pos);
+
+/* Sets a (non-fixed) list of possible audio channel positions
+ * on a structure (this requires the "channels" property to
+ * be fixed!) or on a caps (here, the "channels" property may be
+ * unfixed and the caps may even contain multiple structures). */
+void	gst_audio_set_structure_channel_positions_list
+					(GstStructure *str,
+					 const GstAudioChannelPosition *pos,
+					 gint          num_positions);
+void	gst_audio_set_caps_channel_positions_list
+					(GstCaps      *caps,
+					 const GstAudioChannelPosition *pos,
+					 gint          num_positions);
+
+/* Custom fixate function. Elements that implement some sort of
+ * channel conversion algorhithm should use this function for
+ * fixating on GstAudioChannelPosition properties. It will take
+ * care of equal channel positioning (left/right). Caller g_free()s
+ * the return value. The input properties may be (and are supposed
+ * to be) unfixed. */
+GstAudioChannelPosition *
+	gst_audio_fixate_channel_positions (GstStructure *str);
+
+#endif /* __GST_AUDIO_MULTICHANNEL_H__ */

gst-libs/gst/audio/testchannels.c

@@ -0,0 +1,55 @@
+/* GStreamer Multichannel Test
+ * (c) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <gst/gst.h>
+
+#include <multichannel.c>
+#include <multichannel-enumtypes.c>
+
+gint
+main (gint argc, gchar * argv[])
+{
+  gchar *str;
+  GstCaps *caps;
+  GstAudioChannelPosition pos[2] = { GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
+    GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT
+  };
+
+  /* register multichannel type */
+  gst_init (&argc, &argv);
+  gst_audio_channel_position_get_type ();
+
+  /* test some caps-string conversions */
+  caps = gst_caps_new_simple ("audio/x-raw-int",
+      "channels", G_TYPE_INT, 2, NULL);
+  str = gst_caps_to_string (caps);
+  g_print ("Test caps #1: %s\n", str);
+  g_free (str);
+  gst_audio_set_channel_positions (gst_caps_get_structure (caps, 0), pos);
+  str = gst_caps_to_string (caps);
+  g_print ("Test caps #2: %s\n", str);
+  g_free (str);
+  gst_caps_free (caps);
+
+  return 0;
+}