aacparse: set channels and rate on output caps, and keep codec_data

Create output caps from input caps, so we maintain any fields we
might get on the input caps, such as codec_data or rate and channels.
Set channels and rate on the output caps if we don't have input caps
or they don't contain such fields. We do this partly because we can,
but also because some muxers need this information. Tagreadbin will
also be happy about this.

1 files changed, 17 insertions, 7 deletions

diff --git a/gst/aacparse/gstaacparse.c b/gst/aacparse/gstaacparse.c
index c9ad0b5f9..07567bc73 100644
--- a/gst/aacparse/gstaacparse.c
+++ b/gst/aacparse/gstaacparse.c
@@ -213,17 +213,27 @@ gst_aacparse_finalize (GObject * object)
 static gboolean
 gst_aacparse_set_src_caps (GstAacParse * aacparse)
 {
-  GstCaps *src_caps = NULL;
-  gchar *caps_str = NULL;
+  GstStructure *s;
+  GstCaps *sink_caps, *src_caps = NULL;
   gboolean res = FALSE;
 
-  src_caps = gst_caps_new_simple ("audio/mpeg",
-      "framed", G_TYPE_BOOLEAN, TRUE,
+  sink_caps = GST_PAD_CAPS (GST_BASE_PARSE (aacparse)->sinkpad);
+  GST_DEBUG_OBJECT (aacparse, "sink caps: %" GST_PTR_FORMAT, sink_caps);
+  if (sink_caps)
+    src_caps = gst_caps_copy (sink_caps);
+  else
+    src_caps = gst_caps_new_simple ("audio/mpeg", NULL);
+
+  gst_caps_set_simple (src_caps, "framed", G_TYPE_BOOLEAN, TRUE,
       "mpegversion", G_TYPE_INT, aacparse->mpegversion, NULL);
 
-  caps_str = gst_caps_to_string (src_caps);
-  GST_DEBUG_OBJECT (aacparse, "setting srcpad caps: %s", caps_str);
-  g_free (caps_str);
+  s = gst_caps_get_structure (src_caps, 0);
+  if (!gst_structure_has_field (s, "rate") && aacparse->sample_rate > 0)
+    gst_structure_set (s, "rate", G_TYPE_INT, aacparse->sample_rate, NULL);
+  if (!gst_structure_has_field (s, "channels") && aacparse->channels > 0)
+    gst_structure_set (s, "channels", G_TYPE_INT, aacparse->channels, NULL);
+
+  GST_DEBUG_OBJECT (aacparse, "setting src caps: %" GST_PTR_FORMAT, src_caps);
 
   gst_pad_use_fixed_caps (GST_BASE_PARSE (aacparse)->srcpad);
   res = gst_pad_set_caps (GST_BASE_PARSE (aacparse)->srcpad, src_caps);